Buildroot

The full-featured Debian image may be too cumbersome for some applications. Applications that require faster bootup time or a smaller root filesystem will benefit greatly from using a lighter distribution like Buildroot. Using Buildroot for generating images makes it easy to keep software up to date, both userspace and kernel. Additionally, the use of Buildroot allows for building full images completely from source, with semi-reproducible builds, and full software license reports.

To assist customers heading down this path, we maintain our own Buildroot br2-external tree. This tree includes upstream Buildroot as a submodule, which eases updating between Buildroot releases. See the Buildroot manual for more information on Buildroot and br2-external trees.

In order to provide an easy transition from a larger Linux distribution to Buildroot, we provide and maintain two levels of configurations:

The base configuration for each device brings in hardware support to get the unit booted, but offers minimal software support and relies mostly on tools provided by BusyBox. An "extra packages" defconfig that can be merged in with any of the base configurations in order to provide many additional packages to create an environment that is more consistent with larger Linux distributions. The larger Buildroot configuration averages about 10 seconds of boot time, much of which is spent on networking. The base configurations can reduce this time significantly.

Our Buildroot br2-external currently uses the linux-5.10.y branch of our Linux LTS kernel repository for the majority of its supported platforms.

tip

Note that our base configurations include that device's utilities package where possible. Normally, these utilities (e.g. tshwctl, tsmicroctl, etc.) list the git hash of the build source in the help output. However, due to the Buildroot process, the git hash in these utilities reflects the git hash of Buildroot-ts, NOT of the utilities repository. There is no way to work around this without building the utilities outside of Buildroot.

Installing

When building Buildroot from source, the output files can be used to create a bootable microSD card and a bootable eMMC for the board. The output files are also compatible with our USB Image Replicator.

We also offer a pre-made filesystem tarball that is based on our full Buildroot configuration. It can be downloaded here.

The default configuration was designed to be as close to our stock Debian distribution. This includes our utilities like tsmicroctl, our TS-SILO monitor daemon, drivers, firmware, and software for the Wi-Fi and Bluetooth module, and support for LCD + Keypad.

Building

Buildroot is intended to be completely cross-compiled from a host Linux workstation. This process creates a cross-compiler which is then used to build all target applications, kernel, etc., and then output a bootable image / tarball. The following instructions will create a bootable image / tarball for the target system:

Clone the repository:

git clone --recurse-submodules https://github.com/embeddedTS/buildroot-ts.git
cd buildroot-ts/

Configure the build:

# The following command uses a Buildroot script to merge two config files.
# The extra_packages_defconfig includes more usual packages to match our stock images
./buildroot/support/kconfig/merge_config.sh technologic/configs/extra_packages_defconfig technologic/configs/ts7553v2_defconfig

# A smaller base image can be made with bare hardware support using:
# make ts7553v2_defconfig

At this point, the default configuration can be modified if desired:

make menuconfig

And finally, start the build process:

make

The Buildroot process can take a large amount of time to build depending on available system resources. Note that if any changes occur in the config file, it is recommended to clean the build tree and start the process over. Buildroot ccache is not enabled by default, but can be to help speed up repeated builds. See the Buildroot manual for more information about ccache and Buildroot.

Once it is finished building, Buildroot will output a filesystem tarball to buildroot/output/images/rootfs.tar.xz. This file can be used with the Installing Buildroot instructions to get this tarball booted on the target device.

Cross Compiling

In order to generate a cross-compiler from Buildroot, first configure the target build as outlined in the first steps of the build instructions. Once configured, a separate make command can be issued to generate a tarball package of the cross-compiler. This can be unpacked to any location on the host Linux workstation's filesystem and then used to cross-compile additional applications for the target. The build, setup, and use of the cross-compiler can be done with the following steps:

# Be sure the target is configured first!
# The following command will output the cross-compiler package as well as build the target image completely if not built already
make sdk

# Unpack the tarball to new directory in the users home directory
# Note that the tarball name may be slightly different depending on how the toolchain is configured in Buildroot
mkdir ~/buildroot-toolchain
tar xf buildroot/output/images/arm-buildroot-linux-gnueabihf_sdk-buildroot.tar.gz -C ~/buildroot-toolchain/

# Update the path information for the toolchain (must be done when the tarball is unpacked, or if the root folder of the toolchain is moved!)
# Note that, as above, the path for the compiler may be slightly different depending on how the toolchain is configured in Buildroot
~/buildroot-toolchain/arm-buildroot-linux-gnueabihf_sdk-buildroot/relocate-sdk.sh

# Create a simple Hello World application source
cat << EOF > hello.c
#include <stdio.h>
void main(void) { printf("Hello!\n"); }
EOF

# Build a binary from the Hello World source that can be run on the target device
~/buildroot-toolchain/arm-buildroot-linux-gnueabihf_sdk-buildroot/bin/arm-linux-gcc hello.c -o hello

# This cross compiler can be added to the user's PATH variable for easy access
export PATH=$PATH:~/buildroot-toolchain/arm-buildroot-linux-gnueabihf_sdk-buildroot/bin
arm-linux-gcc hello.c -o hello

The hello binary can then be copied to the target device and executed on it.

Note that the make sdk command can be run at any time to generate the toolchain tarball. Even after Buildroot has generated the output image.

Buildroot is extremely flexible in its generation and use of a cross-compiler. See the Buildroot manual for more information on advanced use of the Buildroot generated toolchain as well as using Buildroot's generated cross-compiler as an external compiler for Buildroot.

Configuring the Network

Buildroot implements the ip, ifconfig, route, etc., commands to manipulate the settings of interfaces. The first Ethernet interface is set up to come up automatically with our default configuration. The interfaces can also be manually set up:

# Bring up the CPU network interface
ifconfig eth0 up

# Set an IP address (assumes 255.255.255.0 subnet mask)
ifconfig eth0 192.168.0.50

# Set a specific subnet
ifconfig eth0 192.168.0.50 netmask 255.255.0.0

# Configure a default route. This is the server that provides an internet connection.
route add default gw 192.168.0.1

# Edit /etc/resolv.conf for the local DNS server
echo "nameserver 192.168.0.1" > /etc/resolv.conf

Most commonly, networks will offer DHCP which can be set up with one command:

# To setup the default CPU Ethernet port
udhcpc -i eth0
# All Ethernet ports can be made active and request DHCP addresses with:
udhcpc

To have network settings take effect on startup in Buildroot, edit /etc/network/interfaces:

# interface file auto-generated by Buildroot

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp
  pre-up /etc/network/nfs_check
  wait-delay 15

Note that the default network startup may timeout on some networks, e.g. network protocols such as STP can delay packet movement. This can be resolved in Buildroot by adding network configuration options to fail after a number of attempts (rather than a timeout) or retry for a DHCP lease indefinitely. For example, adding one of the following lines under the iface eth0 inet dhcp section:

udhcpc_opts -t 0 to infinitely retry
udhcpc_opts -t 5 to fail after five attempts.

See the man page for interfaces(5) for further information on the syntax of the interfaces file and all of the options that can be passed.

For more information on network configuration in general, Debian provides a great resource here that can be readily applied to Buildroot in most cases.

Installing New Software

Buildroot does not include a package manager by default (though it is possible to enable one). This means installing software directly on the platform can be cumbersome and is not the intended path when using Buildroot. It is recommended to modify the Buildroot configuration to include additional packages. See the Building Buildroot section for information on modifying the configuration to build additional packages.

If a desired package is not available in Buildroot, there are a number of options available moving forward. It is possible to add packages to the build process, though this does require some knowledge of Buildroot internals. Another option is to use the cross compiler that is output by Buildroot in order to compile packages on a host system and then copy them over to the target. It is also possible to install a toolchain directly on the device, and compile applications natively. The last option is the least recommended as it greatly increases the final image size and adds unnecessary complexity.

Setting Up SSH

The default configuration has Dropbear set up. Dropbear is a lightweight SSH server.

Make sure the device is configured on the network and set a password for the remote user. SSH will not allow remote connections without a password set. The default configuration does not set a password for the root user, nor are any other users configured.

passwd root

After this setup it is now possible to connect from a remote PC supporting SSH. On Linux/OS X this is the ssh command, or from Windows using a client such as PuTTY.

Starting Software Automatically

Buildroot defaults to using the BusyBox init system, and all of our provided configurations use this as well. The following custom startup script uses this format. For information on other init systems that Buildroot can use, as well as creating startup scripts for these, see the Buildroot manual.

The most straightforward way to add an application to startup is to create a startup script. This example startup script that will toggle the red LED on during startup, and off during shutdown. In this case the script is named customstartup which can be changed as needed.

Create the file /etc/init.d/S99customstartup with the following contents. Be sure to set the script as executable!

#! /bin/sh
# /etc/init.d/customstartup

case "$1" in
  start)
    echo 1 > /sys/class/leds/red-led/brightness
    ## If you are launching a daemon or other long running processes
    ## this should be started with
    # nohup /usr/local/bin/yourdaemon &
    ;;
  stop)
    # if you have anything that needs to run on shutdown
    echo 0 > /sys/class/leds/red-led/brightness
    ;;
  *)
    echo "Usage: customstartup start|stop" >&2
    exit 3
    ;;
esac
  
exit 0

note

The $PATH variable is not set up by default in init scripts so this will either need to be done manually or the full path to your application must be included.

Buildroot provides numerous mechanisms to create this file in the target filesystem at build time. See the Buildroot manual for more information on this.

This script will be automatically called at startup and shutdown thanks to the file location and naming. However, it can also be manually started or stopped:

/etc/init.d/S99customstartup start
/etc/init.d/S99customstartup stop

Features

Battery Backed RTC

The board implements a M41T00S STMicro Battery Backed RTC using an external and replaceable coin cell battery. This RTC is connected to the CPU via I2C and is handled by the kernel and is presented as a standard RTC device in linux.

Bluetooth

On many boards, support for Bluetooth is provided by the BlueZ project. BlueZ supports different profiles for HID, A2DP, and more. Refer to the BlueZ documentation for more information. Please see our BLE Examples page for information on installing BlueZ from source, getting started, and using demo applications.

BlueZ Bluetooth modules can be activated with the following commands:

echo BT_POWER_UP > /dev/wilc_bt
sleep 1
echo BT_DOWNLOAD_FW > /dev/wilc_bt
sleep 1

btattach -N -B /dev/ttymxc2 -S 115200 &
sleep 1
bluetoothctl power on
sleep 1
hcitool cmd 0x3F 0x0053 00 10 0E 00 01
kill %1 # This terminates the above btattach command
sleep 1
btattach -B /dev/ttymxc2 -S 921600 &

At this point, the device is fully set up to be controlled by various BlueZ tools. For example, to do a scan of nearby devices:

bluetoothctl
power on
scan on

This will return a list of devices such as:

root@ts-imx6ul:~# bluetoothctl  
Agent registered
[CHG] Controller F8:F0:05:XX:XX:XX Pairable: yes
[bluetooth]# power on
Changing power on succeeded
[CHG] Controller F8:F0:05:XX:XX:XX Powered: yes
[bluetooth]# scan on
Discovery started
[CHG] Controller F8:F0:05:XX:XX:XX Discovering: yes
[NEW] Device 51:DD:C0:XX:XX:XX Device_Name
[NEW] Device 2A:20:E2:XX:XX:XX Device_Name
[CHG] Device 51:DD:C0:XX:XX:XX RSSI: -93
[CHG] Device 51:DD:C0:XX:XX:XX RSSI: -82
[NEW] Device E2:08:B5:XX:XX:XX Device_Name
[CHG] Device 51:DD:C0:XX:XX:XX RSSI: -93
[CHG] Device 2A:20:E2:XX:XX:XX RSSI: -94
[NEW] Device 68:62:92:XX:XX:XX Device_Name
[NEW] Device 68:79:12:XX:XX:XX Device_Name
[bluetooth]# quit

Other supported commands include:

# Allow the BT chip to enter sleep mode
echo BT_FW_CHIP_ALLOW_SLEEP > /dev/wilc_bt

# Power down the BT radio when not in use
echo BT_POWER_DOWN > /dev/wilc_bt

CAN

note

The TS-7553-V2 Rev. B PCB does not have software control of the CAN_EN# pin for the transceivers and they are always enabled. This is addressed in later hardware revisions.

CAN transceivers are automatically controlled by the kernel. The below table shows an example CAN implementation on the two CAN interfaces of the embeddedTS board. If either of the interfaces are brought up in Linux, then both transceivers will be enabled together. When both interfaces are brought down, then the transceivers will be disabled. By default, when the kernel boots, the interfaces are down, and therefore the transceivers are disabled.

CAN#	LINUX DEV	CAN CONTROLLER	CAN_H LOCATION	CAN_L LOCATION	TERMINATION	NOTES
CPU Flexcan1	can0	FlexCAN	DB9 HEADER_PIN_4	DB9 HEADER_PIN_9	None	Transceiver always enabled on REV. b
CPU Flexcan2	can1	FlexCAN	HD2 COM2 HEADER_PIN_4	HD2 COM2 HEADER_PIN_9	None	Transceiver always enabled on REV. b

In Debian we provide the utilities cansend and candump to test the ports or as a simple packet send/receive tool. To test the two ports together, tie CAN_H of both CAN ports together, doing the same for the CAN_L pins. Then use the following commands:

candump can0 &
cansend can1 7Df#03010c
#This command will return
  can0  7DF  [3] 03010c

The above example packet is designed to work with the Ozen Elektronik myOByDic 1610 ECU simulator to read the RPM speed. In this case, the ECU simulator would return data from candump with:

 <0x7e8> [8] 04 41 0c 60 40 00 00 00 
 <0x7e9> [8] 04 41 0c 60 40 00 00 00 

In the output above, columns 6 and 7 are the current RPM value. This shows a simple way to prove out the communication before moving to another language.

The following example sends the same packet and parses the same response in C:

Sample Code

#include <stdio.h>
#include <pthread.h>
#include <net/if.h>
#include <string.h>
#include <unistd.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <assert.h>
#include <linux/can.h>
#include <linux/can/raw.h>

int main(void)
{
	int s;
	int nbytes;
	struct sockaddr_can addr;
	struct can_frame frame;
	struct ifreq ifr;
	struct iovec iov;
	struct msghdr msg;
	char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) + CMSG_SPACE(sizeof(__u32))];
	char *ifname = "can0";
 
	if((s = socket(PF_CAN, SOCK_RAW, CAN_RAW)) < 0) {
		perror("Error while opening socket");
		return -1;
	}
 
	strcpy(ifr.ifr_name, ifname);
	ioctl(s, SIOCGIFINDEX, &ifr);
	addr.can_family  = AF_CAN;
	addr.can_ifindex = ifr.ifr_ifindex;
 
	if(bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
		perror("socket");
		return -2;
	}
 
 	/* For the ozen myOByDic 1610 this requests the RPM guage */
	frame.can_id  = 0x7df;
	frame.can_dlc = 3;
	frame.data[0] = 3;
	frame.data[1] = 1;
	frame.data[2] = 0x0c;
 
	nbytes = write(s, &frame, sizeof(struct can_frame));
	if(nbytes < 0) {
		perror("write");
		return -3;
	}

	iov.iov_base = &frame;
	msg.msg_name = &addr;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_control = &ctrlmsg;
	iov.iov_len = sizeof(frame);
	msg.msg_namelen = sizeof(struct sockaddr_can);
	msg.msg_controllen = sizeof(ctrlmsg);  
	msg.msg_flags = 0;

	do {
		nbytes = recvmsg(s, &msg, 0);
		if (nbytes < 0) {
			perror("read");
			return -4;
		}

		if (nbytes < (int)sizeof(struct can_frame)) {
			fprintf(stderr, "read: incomplete CAN frame\n");
		}
	} while(nbytes == 0);

	if(frame.data[0] == 0x4)
		printf("RPM at %d of 255\n", frame.data[3]);
 
	return 0;
}

See the Kernel's CAN documentation for more information. Other languages have bindings to access CAN such as Python and Java using JNI.

In production use of CAN we also recommend setting a restart-ms for each active CAN port.

ip link set can0 type can restart-ms 100

This allows the CAN bus to automatically recover in the event of a bus-off condition.

FlexCAN

FlexCAN ports use the Linux SocketCAN implementation. The ports can be set up and used with the following commands:

ip link set can0 up type can bitrate 1000000
ip link set can1 up type can bitrate 1000000

CPU

This device uses the i.MX6UL CPU, running at up to 696 MHz, based upon a Cortex-A7 core and targeting low power consumption.

Refer to NXP's documentation for more detailed information on the i.MX6UL.

GPIO

To interact with DIO pins through the sysfs interface, it first must be exported to userspace, for example, DIO 136 is the En. Relay pin:

echo "136" > /sys/class/gpio/export

If you receive a permission denied on a pin, that means it is claimed by another kernel driver. If the command is successful, there will be a /sys/class/gpio/gpio136/ directory. The relevant files in this directory are:

direction - "out" or "in"
value - write "1" or "0", or read "1" or "0" if direction is in
edge - write with "rising", "falling", or "none"

# Set GPIO 136 high
echo "out" > /sys/class/gpio/gpio136/direction
echo "1" > /sys/class/gpio/gpio136/value
# Set GPIO 136 low
echo "0" > /sys/class/gpio/gpio136/value

# Read the value of GPIO 82, the Push Switch
echo "82" > /sys/class/gpio/export
echo "in" > /sys/class/gpio/gpio82/direction
cat /sys/class/gpio/gpio82/value

Digital I/O (DIO)

When configured as an output, a GPIO line is driven low (GND) or high (3.3 V) by setting its output value through the GPIO character device. The value is controlled by the driver and reflects the requested output state rather than being read back through a value file, as the legacy sysfs interface is not used.

When configured as an input, GPIO lines use internal pull-up resistors by default. GPIO lines can also be configured to generate interrupts on rising and/or falling edges using the character device event interface, with events monitored via poll() or select() on the GPIO file descriptor.

The Linux kernel supports safe GPIO initialization using gpio-hog entries in the device tree, allowing GPIOs to be driven to a known state at early boot.

DIO Lines

DIO (sysfs)	Chip	Line	Function	Location
-- [1]	0	1	En. 5 V to USB host	Internal/external ports
-- [1]	0	8	En. 4 V to CN5 XBee Socket [2]	CN5_1[3]
-- [1]	0	9	En. 3.3 V to CN5 XBee Socket [2]	CN5_1[3]
18	0	18	UART5 CTS	CN9_8
19	0	19	UART5 RTS	CN9_7
23	0	23	RS-232 Shutdown#	N/A
40	1	8	XBee DTR	CN5_9
41	1	9	XBee RTS	CN5_16
46	1	14	XBee CTS	CN5_12
66	2	2	NimbeLink V180	CN5_13
67	2	3	NimbeLink PWR_ON#	CN5_20
75	2	11	NO Charge Jumper#	NO Charge Jumper
81	2	17	SD Boot Jumper#	SD Boot Jumper
82	2	18	Push Switch#	Push Switch
83	2	19	U-Boot Jumper#	U-Boot Jumper
84	2	20	XBee Reset#	CN5_5
117 [4]	3	21	Keypad 0	HD4_2
118 [4]	3	22	Keypad 1	HD4_3
119 [4]	3	23	Keypad 2	HD4_4
120 [4]	3	24	Keypad 3	HD4_5
121	3	25	En. LCD Backlight	N/A
128	4	0	Power Fail	N/A
-- [1]	4	2	En. eMMC power	N/A
135	4	7	En. XBee USB#	N/A
136	4	8	En. Relay	N/A

[1] For kernels 4.9 and below, see Special DIO below for how to control this line.

[2] Only one of these can be enabled at any time. If 0 9 is enabled, 0 8 will be disabled in hardware to prevent damage.

[3] CN5_6, VBUS, will also be affected by this enable. See the XBee Socket section for more information.

[4] Note that using this pin as standard DIO requires unloading the modules used by the Keypad.

Special DIO

note

This section only applies to kernels 4.9 and below, for kernels 5.10 and newer, follow the GPIO table above.

The linux GPIO subsystem has a few shortcomings, specifically, an inability to set default output state from the kernel devicetree. Because of this, a number of DIO are implemented as LEDs in the kernel; pins that control various power supplies. While there is also a regulator subsystem that these could be used with, the regulator controls have their own issues as well. The LED subsystem is a very straightforward way to control IO pins in a similar manner to linux GPIO via the sysfs interface.

To enable a particular output, write a 1 to the brightness file for one of these special DIO. For example, to enable 4V on a CN5 XBee Socket header:

echo 1 > /sys/class/leds/en-modem-5v/brightness

To disable any of the outputs, write a 0 to the brightness file. For example, to disable power to the USB host port:

echo 0 > /sys/class/leds/en-usb-5v/brightness

DIO Line Name	Sysfs Path	Function	Location
en-usb-5v	/sys/class/leds/en-modem-5v/brightness	Enable 5 V to USB host	Internal and external USB host
en-modem-5v[1]	/sys/class/leds/en-modem-5v/brightness	Enable 4 V to CN5 XBee Socket	CN5_1[2]
en-xbee-3v3[1]	/sys/class/leds/en-xbee-3v3/brightness	Enable 3.3 V to CN5 XBee Socket	CN5_1[2]
en-emmc	/sys/class/leds/en-emmc/brightness	Enable power to the eMMC device	N/A

[1] Only one of these can be enabled at any time. If en-xbee-3v3 is enabled, en-modem-5v will be disabled in hardware to prevent damage.

[2] CN5_6, VBUS, will also be affected by this enable. See the XBee Socket section for more information.

eMMC

Our default programming of the eMMC is the same as the SD card image for standard partitions.

The default software image contains 3 partitions:

Device	Contents
/dev/mmcblk1	Full eMMC block device
/dev/mmcblk1boot0	eMMC boot partition
/dev/mmcblk1boot1	eMMC boot partition
/dev/mmcblk1p1	Full Debian linux partition

This platform includes an eMMC device, a soldered down MMC flash device. Our off the shelf builds are 4 GB, but up to 64 GB are available for customized builds. The eMMC flash appears to Linux as an SD card at /dev/mmcblk1. Our default programming of the eMMC is the same as the SD card image for standard partitions, but includes additional boot partitions that are used by U-Boot and are not affected by the eMMC partition table.

The eMMC module has a similar concern by default to SD cards in that they should not be powered down during a write/erase cycle. However, this eMMC module includes support for setting a fuse for a "Write Reliability" mode, and a "psuedo SLC (pSLC)" mode. With both of these enabled all writes will be atomic to 512 B and each NAND cell will be treated as a single layer rather than a multi-layer cell. If a sector is being written during a power loss, a block is guaranteed to have either the old or new data. Even in cases where the wrong data is present on the next boot, fsck is often able to deal with the older data being present in a 512 B block. The downsides to setting these modes are that it will reduce the overall write speed and halve the available space on the eMMC to roughly 1.759 GB. Please note that even with these settings, Technologic Systems strongly recommends designing the end application to eliminate any situations where a power-loss event can occur while any disk is mounted as read/write. The TS-SILO option can help to eliminate the dangerous situation.

The "mmc-utils" package is used to enable these modes. The command is pre-installed on the latest image. Additionally we have created a script to safely enable the write reliability and pSLC modes. Since the U-Boot binary and environment reside on the eMMC, care must be taken to save the current state of the boot partitions, enable the modes, restore the boot partitions, and re-enable proper booting options. This script can be used in combination with the production mechanism scripting to complete these steps as part of an end application production process.

danger

Enabling these modes causes all data on the disk to become invalid and must be rewritten. Do not attempt to run the 'mmc' commands from the script individually, all steps in the script must occur as they are or the unit may be unable to boot. If there are any failures of the script, care must be taken to resolve any issues while the unit is still booted or it may fail to boot in the future.

danger

The script is only compatible with Rev. D or newer PCBs. Running the script on any previous PCB revision WILL result in the unit being unable to boot! There is no safe way to enable these modes on previous PCB revisions.

warning

Enabling these modes is a one-way operation, it is not possible to undo them once they are made. Because of this, setting these eMMC modes will invalidate Technologic Systems' return/replacement warranty on the unit. See the warranty section for more information on this.

The emmc_reliability script can be found in the TS-7553-V2 utilities github repository.

The script must be run when boot from any media other than eMMC, such as SD, NFS, or USB. No partition of the eMMC disk can be mounted when these commands are run. Doing so may result in corruption or inability for the unit to boot. Once the pSLC mode is enabled, all data on the disk will become invalid. This means the partition table will need to be re-created, the filesystems formatted, and all filesystem contents re-written to disk. This is why we recommend using this script in conjunction with the production mechanism scripting. The emmc_reliability script can be run first, then the rest of the production script can create and format the partitions as well as write data to disk.

The script requires a single argument, the device node of the eMMC disk, and will output verbosely to stderr. Any specific errors will also be printed out on stderr.

Example usage:

./emmc_reliability /dev/mmcblk1

Upon successful run, the script will return 0. Any errors will return a positive code. See the script for detailed error code information.

Ethernet Port

The NXP processor implements a 10/100 ethernet controller with support built into the Linux kernel. Standard Linux utilities such as ifconfig/ip can be used to control this interface. See the Configuring the Network section for more details. For the specifics of this interface see the CPU manual.

FEC PTP Support

PTP is supported in Linux via the linuxptp project. This allows synchronizing the system clock to within ±1 us.

Note that Linux kernel version 4.9 or greater is required for PTP support with the i.MX6UL CPU. An example of setting up an ethernet interface with PTP and adjusting the clock based on that is below.

apt-get install linuxptp -y

# For PTP on eth0
phc2sys -s /dev/ptp0 -w &
ptp4l -2 -H -i eth0 -m -p /dev/ptp0 &

# For PTP on eth1
phc2sys -s /dev/ptp1 -w &
ptp4l -2 -H -i eth1 -m -p /dev/ptp1 &

If the clocks are significantly off this may take time for the clocks to converge.

FRAM

This platform supports a soldered-down, non-volatile Ferroelectric RAM (FRAM) device. The Cypress FM25L16B is a 2 KiB FRAM device in a configuration not unlike an SPI EEPROM. The nature of FRAM means it is non-volatile, incredibly fast to write, and is specified with 100 trillion read/write cycles (per each of the 256 sequential 8 byte rows) with a 150 year data retention at temperatures below 65 °C. The device is connected to Linux and presents itself as a flat file that can be read and written like any standard Linux file.

The EEPROM file can be found at /sys/class/spi_master/spi2/spi2.2/eeprom.

I2C

The Linux kernel exposes I2C buses as /dev/i2c-# device nodes.

Standard Linux i2c-tools such as i2cdetect, i2cget, and i2cset may be used to interact with I2C devices. Custom kernel and userspace clients may be written as needed.

The list below is a representation of I2C buses on the embedded TS TS-7553-v2, showing logical bus numbers as well as the device number enumerated by the Linux kernel.

I2C Buses

I2C#	I2C Device	Address	Description
CPU I2C1	I2c-0	0x2a	Supervisory microcontroller
		0x68	Battery backed RTC
CPU I2C2	I2c-2	N/A	Daughter Card I2C header 9 (HD1 Pin Header)
CPU I2C3	I2c-3	0x68	Optional MPU-9250 IMU

CPU I2C1 (I2c-0) — Under Linux, I2C 1 bus appears as /dev/i2c-0 .
CPU I2C2 (I2c-2) — This bus is used with CPU GPIO pins rather than an internal SPI peripheral and appears under Linux as /dev/i2c-2
CPU I2C3 (I2c-3) — Under Linux, this bus appears as /dev/i2c-3 .

Additional I2C buses may be implemented using available GPIO pins if further interfaces are required. An example configuration is available.

IMU

Accelerator/Gyro (MPU-9150)

note

Images dated December 15th, 2017 and older need a userspace helper tool, bb_mpu9150, in order to access the IMU data. See this page for instructions on how to obtain and build this tool if needed.

On PCB revision D and below, this platform can support an MPU-9250 Inertial Measurement Unit (IMU) device. This provides a Microelectromechanical Systems (MEMS) gyroscope, accelerometer, and magnetometer.

The gyroscope can be configured for ±250/±500/±1000/±2000 degrees per second (dps). The accelerometer can be configured for ±2/±4/±8/±16 standard gravity (g). And the magnetometer has a range of ±4800 microteslas (μT). A temperature sensor is also included in the device as well.

The IMU is supported by the kernel and configuration of the device as well as readings can be taken directly from the sysfs IIO interface.

The magnetometer is a separate silicon die inside of the single package device, it needs to be manually instantiated on each boot as the driver is normally not aware of it. This can be done with the command:

echo ak8975 0x0c > /sys/bus/i2c/devices/i2c-4/new_device

At this point, the gyroscope and accelerometer will appear under files in /sys/bus/iio/devices/iio:device0/ while the magnetometer files are populated in /sys/bus/iio/devices/iio:device1/.

Reading the Accelerometer

The raw value for each accelerometer axis can be read by directly reading the associated file. These can be multiplied by the contents of the file in_accel_scale in order to get the acceleration value in m/s².

# TS-7553-V2 sitting flat on a desk
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_accel_scale 
0.000598
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_accel_x_raw 
336  # (0.000598*336) == 0.2 m/s²
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_accel_y_raw 
140 # (0.000598*140) == 0.08 m/s²
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_accel_z_raw 
16080 # (0.000598*16080) == 9.6 m/s²

As the angular errors of the floor, desk, and pin protrusion on the bottom of the TS-7553-V2 add up, it can be observed that the accelerometer is not perfectly flat and is instead at a slight angle.

Reading the Gyroscope

Similar to the accelerometer above, raw information can be read from the gyroscope about the current rotation. These values can be multiplied by the scale in order to get the current movement in degrees per second.

# TS-7553-V2 sitting flat on a desk
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_scale 
0.001064724
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_x_raw 
-19 # (0.001064724*-19) == -0.02 dps
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_y_raw 
-2 # (0.001064724*-2) == -0.002 dps
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_z_raw 
-6 # (0.001064724*-6) == -0.006 dps

# TS-7553-V2 measured while being rotated in free air by hand
# Note that, these are not simultaneous measurements, it is possible to set up the IIO system to get very close to simultaneous measurements however
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_x_raw 
2020 # (0.001064724*2020) == 2.15 dps
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_y_raw 
-12597 # (0.001064724*-12597) == -13.41 dps
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device0/in_anglvel_z_raw 
-2508 # (0.001064724*-2508) == -2.67 dps

In the first block, it can be observed that the values returned are so low they can be attributed to sensor noise, error, and any micro movements transferred from the desk in to the TS-7553-V2.

Reading the Magnetometer

Be sure to enable the magnetometer as described at the beginning of this section! Note that it will show up as a separate IIO device number, but will have similar raw and scale files that can be used to calculate orientation in space relative to magnetic north. For the magnetometer, the driver exposes a scale for each axis rather than a single scale shared by all.

# TS-7553-V2 sitting flat on a desk
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device1/in_magn_x_scale 
0.003574
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device1/in_magn_x_raw   
37 # (0.003574*37) == 0.1322 μT
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device1/in_magn_y_scale 
0.003574
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device1/in_magn_y_raw   
56 # (0.003574*56) == 0.2 μT
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device1/in_magn_z_scale 
0.003457
root@ts-imx6ul:~# cat /sys/bus/iio/devices/iio\:device1/in_magn_z_raw   
36 # (0.003457*36 == 0.1244 μT

The heading can be calculated from the X and Y axes, with the Z axis added in, a full tilt-compensated heading can be calculated.

Accelerometer (ST ISM330)

note

This accelerometer is only present on PCB Rev. E and later. For the accelerometer on earlier PCB revisions, see Accelerator/Gyro (MPU-9150)

This platform features an ST ism330dhcx accelerometer / gyroscope. The accelerometer has an acceleration range of ±2/±4/±8/±16 g.

The accelerometer is accessed through IIO with channels:

accel_x
accel_y
accel_z
timestamp

For example:

# ISM330DHCX
iio_attr -c ism330dhcx_accel accel_x
iio_attr -c ism330dhcx_accel accel_y
iio_attr -c ism330dhcx_accel accel_z

The below examples will be written for the ism330dhcx_accel, but if this fails instead use the ism330dlc_accel device. These commands will provide a single sample of all of the values:

root@tsimx6ul:~# iio_attr -c ism330dhcx_accel accel_x
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'injection_raw', ERROR: Permission denied (-13)
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'raw', value '-183'
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_x' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'
root@tsimx6ul:~# iio_attr -c ism330dhcx_accel accel_y
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'injection_raw', ERROR: Permission denied (-13)
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'raw', value '-292'
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_y' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'
root@tsimx6ul:~# iio_attr -c ism330dhcx_accel accel_z
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'injection_raw', ERROR: Permission denied (-13)
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'raw', value '16491'
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'

To get the real world value, multiply the scale * the raw value. In this case:

X: -0.109434 g
Y: -0.174616 g
Z: 9.861618 g

The default scale is ±2, but ±2/±4/±8/±16 can be selected by setting the scale:

dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale', value '0.000598'
dev 'ism330dhcx_accel', channel 'accel_z' (input), attr 'scale_available', value '0.000598 0.001196 0.002392 0.004785'

To set ±4, you would write the second available scale:

iio_attr -c ism330dhcx_accel accel_x scale 0.001196

The scale values are not independent on this device, and setting x/y/z will set the scale for all 3.

This driver also supports pulling continuous samples using the buffer interface. These can be accessed using iio_readdev:

iio_readdev ism330dhcx_accel -T 0 -s 128 > samples.bin

The format of this file is specified with iio_attr:

root@tsimx6ul:~# iio_attr -c ism330dhcx_accel
dev 'ism330dhcx_accel', channel 'accel_x' (input, index: 0, format: le:S16/16>>0), found 4 channel-specific attributes
dev 'ism330dhcx_accel', channel 'accel_y' (input, index: 1, format: le:S16/16>>0), found 4 channel-specific attributes
dev 'ism330dhcx_accel', channel 'accel_z' (input, index: 2, format: le:S16/16>>0), found 4 channel-specific attributes
dev 'ism330dhcx_accel', channel 'timestamp' (input, index: 3, format: le:S64/64>>0), found 0 channel-specific attributes

The samples are padded to the nearest 8-bytes, so this means the binary format is:

Bits	Description
15:0	accel_x, little endian, signed
15:0	accel_y, little endian, signed
15:0	accel_z, little endian, signed
63:0	timestamp, little endian, signed
15:0	Padding

The unix utility hexdump supports formatting options which can parse these fields:

root@tsimx6ul:~# hexdump samples.bin --format '1/2 "X:%d " 1/2 "Y:%d " 1/2 "Z:%d " 1/8 "TS:%d" 1/2 "" "\n"' | head -n 4
X:-95 Y:-163 Z:8221 TS:200185381271666439
X:-107 Y:-147 Z:8248 TS:200190332264480519
X:-100 Y:-155 Z:8263 TS:200195283888013063
X:-95 Y:-159 Z:8253 TS:200200232540667655

This gives the raw values which can then be multiplied by the scale to get the real world value.

The IIO library can also be used to fill buffers with samples for processing. For example:

#!/usr/bin/env python3

import struct
import iio

ctx = iio.Context('local:')
ctx.set_timeout(0)
dev = ctx.find_device('ism330dhcx_accel')

with open(f'/sys/bus/iio/devices/{dev.id}/sampling_frequency', 'w') as f:
	f.write(f"833.000")

for chan_name in ["accel_x", "accel_y", "accel_z"]:
	chn = dev.find_channel(chan_name)
	chn.enabled = True

# We will request 64 samples at a time
buffer = iio.Buffer(dev, 64, False)
# sample size (3x 16-bit signed data)
sample_size = 6
# Refill and process the buffer
buffer.refill()
data = buffer.read()
for i in range(0, len(data), sample_size):
	if i + sample_size <= len(data):
		x, y, z = struct.unpack('<hhh', data[i:i+sample_size])
		print(f'  accel_x={x}, accel_y={y}, accel_z={z}')

for chn in dev.channels:
	chn.enabled = False

This can also be done using the C library:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <iio.h>

#define NUM_CHANNELS 3
#define SAMPLE_SIZE 6 // 3x 16-bit signed data (2 bytes per axis)

void process_samples(struct iio_buffer *buffer, size_t sample_size) {
    char *data = iio_buffer_start(buffer);
    size_t buffer_size = iio_buffer_end(buffer) - iio_buffer_start(buffer);
    int16_t x, y, z;

    for (size_t i = 0; i < buffer_size; i += sample_size) {
        memcpy(&x, &data[i], sizeof(x));
        memcpy(&y, &data[i + sizeof(x)], sizeof(y));
        memcpy(&z, &data[i + 2 * sizeof(x)], sizeof(z));
        printf("accel_x=%d, accel_y=%d, accel_z=%d\n", x, y, z);
    }
}

int main() {
    struct iio_context *ctx;
    struct iio_device *dev;
    struct iio_channel *channels[NUM_CHANNELS];
    struct iio_buffer *buffer;
    const char *channel_names[NUM_CHANNELS] = { "accel_x", "accel_y", "accel_z" };

    // Create context and find device
    ctx = iio_create_local_context();
    if (!ctx || !(dev = iio_context_find_device(ctx, "ism330dhcx_accel")) &&
        !(dev = iio_context_find_device(ctx, "ism330dlc_accel"))) {
        fprintf(stderr, "Unable to create context or find device\n");
        iio_context_destroy(ctx);
        return 1;
    }

    // Enable channels and set sampling frequency
    for (int i = 0; i < NUM_CHANNELS; i++) {
        channels[i] = iio_device_find_channel(dev, channel_names[i], false);
        if (!channels[i] || iio_channel_attr_write(channels[i], "sampling_frequency", "833.000") < 0) {
            fprintf(stderr, "Unable to find or configure channel %s\n", channel_names[i]);
            iio_context_destroy(ctx);
            return 1;
        }
        iio_channel_enable(channels[i]);
    }

    // Create buffer and process samples
    buffer = iio_device_create_buffer(dev, 64, false);
    if (!buffer || iio_buffer_refill(buffer) < 0) {
        fprintf(stderr, "Unable to create or refill buffer\n");
        iio_context_destroy(ctx);
        return 1;
    }

    process_samples(buffer, SAMPLE_SIZE);

    // Cleanup
    iio_buffer_destroy(buffer);
    iio_context_destroy(ctx);

    return 0;
}

Gyroscope (ST ISM330)

note

This gyroscope is only present on PCB Rev. E and later

This platform features an ST ism330dhcx accelerometer / gyroscope. The gyroscope has a selectable angular range of ±125/±250/±500/±1000/±2000 dps

The gyroscope is accessed through IIO with channels:

anglvel_x
anglvel_y
anglvel_z
timestamp

Magnetometer (ST IIS2MDCTR)

note

This magnetometer is only present on PCB Rev. E and later

This board includes an ST IIS2MDCTR 3-axis magnetometer, which has a magnetic field dynamic range of ±50 gauss (16 bits of precision at up to 150 Hz).

The magnetometer is accessed through Linux's industrial I/O (IIO) subsystem as iis2mdc with channels:

magn_x
magn_y
magn_z
timestamp

For example:

root@tsimx6ul:~# iio_attr -c iis2mdc -c magn_x
dev 'lis2mdl_magn', channel 'magn_x' (input), attr 'raw', value '630'
dev 'lis2mdl_magn', channel 'magn_x' (input), attr 'scale', value '0.001500'
root@tsimx6ul:~# iio_attr -c iis2mdc -c magn_y
dev 'lis2mdl_magn', channel 'magn_y' (input), attr 'raw', value '-165'
dev 'lis2mdl_magn', channel 'magn_y' (input), attr 'scale', value '0.001500'
root@tsimx6ul:~# iio_attr -c iis2mdc -c magn_z
dev 'lis2mdl_magn', channel 'magn_z' (input), attr 'raw', value '9'
dev 'lis2mdl_magn', channel 'magn_z' (input), attr 'scale', value '0.001500'

note

The 5.10 LTS kernel did not have the same "iis2mdc" driver, but uses a drop in under the name "lis2mdl". use this as the device name on 5.10 instead.

This shows a snapshot of the x, y, z values. To get the measured field strength along each axis, multiply the scale by the raw value to get the actual reading in milligauss. In the above example:

X: 0.945 mG (milligauss)
Y: -0.2475 mG
Z: 0.0135 mG

Jumpers

The TS-7553-V2 has a set of jumpers located near the supercapacitors on the edge of the SBC. These jumpers control a number of aspects of the TS-7553-V2's behavior. The jumpers are labeled on the silkscreen rather than numbered:

Label	Description
NO Charge	When jumper is set, disable charging of the supercapacitors. Beneficial for early development and testing.
SD Boot	When jumper is set, boot kernel and Debian from the SD card. Otherwise boot kernel and Debian from eMMC. This jumper influences U-Boot behavior.
U Boot	When jumper is set, pause booting in U-Boot and drop to a U-Boot shell. Otherwise boot straight to Debian.
CAN	When jumper is set, adds a 120 ohm termination resistor across CAN1 H and L pins. (Note: the CAN2 interface always has a 120 ohm termination)
485	When jumper is set, adds a 120 ohm termination resistor across RS-485 + and - pins.

LCD + Keypad

The TS-7553-V2 supports an optional 128x64 px. monochrome LCD and 4 membrane switches all mounted in an enclosure. The LCD uses a simple SPI interface and is set up with a kernel driver to be a simple framebuffer. Fairly complex graphics can be created on the screen through the use of graphical libraries such as Cairo. The keypad is a simple 4 button keypad that is attached to the system through GPIO with a driver that behaves like a keyboard input. We have created a helper application as well as tests/demos for the LCD and keypad functionality. The sources can be found in the TS-7553-V2 Utilities github. The binaries are included in the default image.

The backlight can be controlled through a DIO pin and is automatically turned on when the helper application is started.

LCD

In order for the LCD to run, there is a module that must first be loaded, ts-st7565p-fb. On the TS-7553-V2, this module is auto-loaded by systemd, it's specified in /etc/modules-load.d/lcd_keypad.conf

The 128x64 px. monochrome LCD is connected to the system via SPI and uses a userspace application to format the data, and a driver to send it to the device. The LCD can be used as a generic framebuffer with this setup. The userspace application and driver are included by default, but must be manually run to set up.

/usr/local/bin/lcd-helper

Note that its possible with systemd to set this up to auto run on startup, followed by the application that would utilize the screen. This application should start up after all of the necessary modules have been loaded and the helper application has been started.

Two example binaries are also included in order to demonstrate the LCD's capabilities.

/usr/local/bin/cairo-test

Is a simple Cairo demonstration that draws a box, a line, a circle, and some text on to the display.

/usr/local/bin/bounce-test

Will display a bouncing box on the screen.

See the sources for more information on these demos and how they operate.

Keypad

Keypad In order for the membrane switches to run properly, there are two modules that must be loaded, gpio_keys, and matrix_keymap. On this board, these modules are auto-loaded by systemd, these are specified in /etc/modules-load.d/lcd_keypad.conf

The 4 button membrane keypad allows for a 4 button input. These are set up on GPIO pins, and are connected to the system as a standard input event device. The four buttons are connected as arrow keys. An example binary is included in order to demonstrate the input capabilities of these buttons:

/usr/local/bin/keypad-test

Will draw a box around the screen with some text. When a button is pressed, it will display a block on the LCD above the button that has been pressed. Please note that the LCD device must first be set up and operational before this binary will launch.

See the sources in github for more information on this demo and how it operates.

The keypad modules can be prevented from loading, allowing use of the keypad pins as DIO. This can be accomplished with the following command:

echo "blacklist gpio_keys" > /etc/modprobe.d/keypad-blacklist.conf
# Remove the above file to re-enable module loading automatically at startup.

LEDs

LEDs can be manipulated from userspace using the LED sysfs interface. The LEDs have 4 behaviors from default software:

Green Behavior	Red behavior	Meaning
Solid On	Off	The kernel has booted and the system is running.
Off	Solid On	The unit has powered on and is in the bootloader.
On for 10s, off for 100ms, and repeating	On for 10s, off for 100ms, and repeating	The watchdog is continuously resetting the board. This happens when the system cannot find a valid boot device, or the watchdog is otherwise not being fed. This is normally fed by the kernel once a valid boot media has started. See the Watchdog Timer section for more details.
Off	Off	The device is unable to boot. Typically either it is not being supplied with enough voltage, or the unit has been otherwise damaged. If a stable voltage is being provided and the supply is capable of providing at least 1A to the unit, an RMA is suggested.
Off	Blinking about 5ms on, about 10ms off.	The device is receiving too little power, or something is drawing too much current from the unit's power rails causing the unit to reboot consistently.

The red and green LEDs can be controlled from userspace after bootup using the sysfs LED interface. For example, to turn on the red LED:

echo 1 > /sys/class/leds/red-led/brightness

A number of triggers are also available, including timers, disk activity, and heartbeat. These allow the LEDs to represent various system activities as they occur. See the kernel LED documentation for more information on triggers and general use of LED class devices.

We also use the LED control system to control a number of DIO pins which need to have their default state specified. See the DIO section for more information on this.

microSD Card Interface

The i.MX6UL SD card controller internal to the CPU provides support for microSD cards and is fully compliant with the SD specification. This controller has been tested with Sandisk Extreme SD cards which allow read speeds up to 20.5MB/s, and write speeds up to 21.5MB/s.

Our default software image contains a single partition:

Device	Contents
/dev/mmcblk0	SD Card block device
/dev/mmcblk0p1	Full Debian linux partition

Reboot Source

The supervisory microcontroller is capable of saving and displaying the reason for the most recent reboot. This can be used to detect various errors that may occur in the field, as well as simple accounting of events. The source can be queried with tsmicroctl:

tsmicroctl -i

reboot_source=poweron

Possible sources and causes are:

Source	Possible causes
poweron	Power removed, supercapacitors discharged, and then power applied
brownout[1]	Like "poweron," however the supercapacitors have not fully discharged.
WDT	WDT timeout; reboot command (which reboots via WDT)
sleep	The system has woken up from a sleep command

[1] This situation is rare due to how the microcontroller handles TS-SILO. A loss of external power with safe shutdown will result in a "WDT" event.

Relay

The TS-7553-V2 has one SPDT relay rated for 5 A at 277 VAC or 30 VDC that can be toggled through a DIO pin. The PCH-105D2H relay closes in 10ms, and opens in 5ms. A very safe assumption would be that it will switch after 20ms. The common, NO (Normally Open), and NC (Normally Closed) connections are brought out on the screw terminal pin header. See the DIO section of the manual for information on manipulating the relays.

Contact	Location
COM	P1_7
NC	P1_8
NO	P1_6

Sleep

note

As soon as the sleep command is issued the unit will go to sleep. If the proper precautions are not taken, filesystem corruption can result as the sleep mode removes all power from the CPU and other peripherals on the SBC

The device implements a very low power sleep mode using the on-board supervisory microcontroller. This allows powering off the CPU and associated peripherals entirely for a specified period of time. This mode offers extreme power savings, only requiring around 200 mW of power, with the ability to wake up after an arbitrary timeout (up to 1847297s, which is 21d 9h 8m 17s) with a 1s resolution.

The sleep mode can be entered by calling, for example, tshwctl --sleep 60 to sleep for 60 seconds, but this typically should not be called directly. This would be equivalent to disconnecting power while booted which can cause data loss.

The Debian distribution uses systemd to manage shutdown. When systemd shuts down it will call all executables in the directory /lib/systemd/system-shutdown/. Create a script with the name of "silabs-sleep" in said directory with these contents:

#!/bin/bash

tsmicroctl --sleep 60

And make it executable:

chmod a+x /lib/systemd/system-shutdown/silabs-sleep

Now the platform will sleep immediately following a shutdown. It is safe during the sleep mode to disconnect power. In general, if power is removed and restored, the unit will boot up again immediately as the microcontroller has lost power and would reset.

Note however, that if using the TS-SILO supercapacitors, if external power is removed but the supercapacitors have enough of a charge to keep the microcontroller powered, re-applying power will not boot the device up as the microcontroller is still in sleep mode.

SPI

The i.MX6UL CPU has a native SPI peripheral that is used in a number of places on the board. Additionally, kernel spidev support is added to allow SPI access from userspace. User SPI can be used for LCD access, a generic SPI connection on HD1, as well as user accessible FRAM.

The ECSPI peripheral in the i.MX6UL CPU is highly flexible and can even support SPI slave mode. For more information on the peripheral itself, please see the CPU reference manual.

The SPI peripheral is accessible as /dev/spidev2.x, where x is one of the three chip select lines. Additional chip select lines can be implemented if needed by adding them to the kernel device-tree by using GPIO.

CS	Device
0	LCD CS
1	HD1
2	FRAM

See the kernel spidev documentation for more information on interfacing with the SPI peripherals.

Supervisory Microcontroller

The board includes an on-board supervisory microcontroller. It is an 8051 based device that has a number of operational responsibilities. It creates a USB serial UART for the debug UART, manages power-up and reset sequencing which includes deep sleep mode, manages charging the TS-SILO SuperCaps, is the system WDT, and has a number of ADC inputs of various system voltages.

Information about the microcontroller as well as output from its internal ADCs can be retrieved with the command:

tsmicroctl -i

Since the microcontroller handles power-up and reset, it includes a low power "sleep" mode that removes power from the CPU and all peripherals for a predefined period of time. Note that as soon as the sleep command is issued, the microcontroller will more power from all peripherals. Care must be taken to ensure there is no damage to peripherals or data losses occurring during this sudden power-off event. It is recommended to run this command as the last step after a proper Linux shutdown sequence.

Sleep mode can be entered with the command:

tsmicroctl --sleep <time in seconds>

After the internal timer expires, the microcontroller will run the power-up sequence and boot the whole system back up normally.

On platforms that support TS-SILO supercapacitor backup, tsmicroctl can be used to control that charging from userspace. The microcontroller itself has been carefully tuned to charge the supercapacitors at a safe rate, these parameters are not adjustable. However charging can be enabled and disabled from the command line:

# Enable charging
tsmicroctl --tssiloon

# Disable charging
tsmicroctl --tssilooff

TS-SILO Supercapacitors

The board can optionally support our TS-SILO technology. This consists of a charge and feedback monitor in the supervisory microcontroller, a dedicated charging circuit, and a pair of 2.7 V, 25 F supercapacitors. This provides up to 65 seconds of back up power if external power is removed from the device. Additionally, a notification of power failure is asserted on a CPU GPIO pin when external power has fallen below a valid input level. Monitoring this signal can be used to initiate a proper reboot and ensure that all data is flushed from cache to disk, and all disks are unmounted properly.

Using a reboot is important as issuing a shutdown command will put the kernel in a halted state with no way to cycle it back on so long as the supercapacitors are providing backup power. A reboot will get the system back to the U-Boot shell which by default will monitor the Power Fail input and will only continue to boot to the operating system if input power is valid.

In order to reduce mechanical stress of the supercapacitors due to vibration, the supercapacitors may be secured to the PCB with a silicone adhesive. We have found this to provide a secure but pliable anchoring for the supercapacitors in all environments. See the PCS notice regarding this for more information.

The supercapacitor charge and discharge are monitored by the microcontroller on the TS-7553-V2. A charge cycle is initiated automatically at startup by U-Boot, and can be disabled via a jumper setting. Once a charge cycle is started, the microcontroller will fully charge the supercapacitors and keep them topped off until charging is explicitly disabled. U-Boot can also be configured to load the kernel and FDT, but delay starting them until the supercapacitors are at a specified charge level. This can allow for a guaranteed available amount of reserve power in the case of external power being disconnected once the kernel starts booting.

Manual enabling and disabling of charging can be handled in U-Boot or Linux userspace:

# Enable the supercapacitor charging cycle in U-Boot or Linux userspace
tsmicroctl -e
 
# Disable the supercapacitor charging cycle in U-Boot or Linux userspace
tsmicroctl -d
 
# Get current charge level information from Linux userspace tools
tsmicroctl --info

U-Boot Settings

When the "No Charge" jumper is removed from the device, U-Boot will automatically start charging the supercapacitors at startup. It is also possible to to configure U-Boot to delay booting Linux until the capacitors are at a certain charge level. This is automatically manged with the environment variable chrg_pct. If the No Charge jumper is removed, then U-Boot will begin charging, load the kernel and FDT, and then delay executing them until the supercapacitors are charged to a level equal to or greater than the value of chrg_pct. Setting this value to a 0 will disable the wait functionality. Additionally, if the environment variable chrg_verb is set to 1, then U-Boot will print out the current charge level once every second. If the No Charge jumper is set, then U-Boot will not enable charging automatically.

Note that once charging is started, the supercapacitors will continue to be charged and managed by the microcontroller. In other words, once chrg_pct is reached and U-Boot boots the kernel, the supercapacitors will still continue to charge to 100% and remain topped off unless explicitly disabled.

Our monitor script, /usr/local/bin/tssilomon, will issue a reboot if the external power is removed and the supercapacitor charge drops below a set threshold. This threshold can be tuned to lower values to allow the system to continue to operate during short power loss events where the system is briefly supported by the supercapacitors. When tuning this value, we strongly recommend testing in final application to ensure enough power is available for a complete shutdown cycle in the case of a longer power loss event.

The supervisory microcontroller will also not allow the TS-7553-V2 to boot if power input is not valid. This means that if the system reboots safely due to a power failure, it will remain in a powered off state until external power is re-applied, or the supercapacitors discharge below the sustainable threshold. Once external power is restored, U-Boot will continue booting as it would normally.

We recommend a chrg_pct value of 60. 60% is enough of a charge level in most applications to be able to boot up fully, have our background monitor script detect that external power has been removed, and reboot the system with about 10 seconds of remaining power to handle any potential variances. We strongly recommend testing in a final application to ensure a safe process. Note that the supercapacitors may be at 0% for a large period of time while charging. The 0% charge level is any charge level that is unable to sustain the device if power is removed at that point in time.

An example of this process:

# From the U-Boot shell
env set chrg_pct 60
env set chrg_verb 1
env save

# Now, boot unit without stopping at U-Boot prompt
...
CPU:   Freescale i.MX6UL rev1.1 at 396 MHz
...
Booting from the SD card ...
...
Waiting until SuperCaps are charged to 60%
0%
...
55%
57%
59%
60%
...
Starting kernel ...

Charge and Discharge Times

On average, it will take about 20 seconds to charge the supercapacitors to 100%. This is assuming the supercapacitors have very recently fallen below the threshold voltage to sustain the TS-7553-V2, and that the unit is powered with a 12 V input. Note that at 5 V input the charge current is much lower in order to reduce strain on the power supply. This has the side effect of having an increased charge time compared to 12 V input.

The graph below highlights typical charge and discharge cycles.

Silo Graph

The green line represents seconds vs charge voltage of the supercapacitors with a 12 V input. The red line is the minimum charge voltage of the supercapacitors to sustain operation of the TS-7553-V2. The blue line represents the supercapacitor charge level during an external power failure while the CPU is idling with no ethernet connection. The orange line represents supercapacitor charge level during an external power failure with the CPU fully under load, constant network activity, and the relay coil energized.

UARTS

The TS-7553-V2 CPU offers 8 UARTs. The table below lists the CPU UARTs with their pin locations.

Num.	Dev. Name	Type	TX / + Loc.	RX / - Loc.	RTS Loc.	CTS Loc.
0	ttymxc0	USB Console	N/A	N/A	N/A	N/A
1	ttymxc1	RS-485	CN9_1 / P1_3 / HD2_1	CN9_6 / P1_4 / HD2_6	N/A	N/A
2	ttymxc2	Bluetooth	N/A	N/A	N/A	N/A
3	ttymxc3	RS-232[1]	HD2_3	HD2_2	N/A	N/A
4	ttymxc4	RS-232[1]	HD2_7	HD2_8	N/A	N/A
5	ttymxc5	RS-232[1]	CN9_3	CN9_2	CN9_7[2][3]	CN9_8[2][4]
6	ttymxc6	TTL	HD1_12	HD1_10[5]	N/A	N/A
7	ttymxc7	XBee/TTL	CN5_3	CN5_2	N/A	N/A

[1] RS-232 transceiver can be shut down to reduce power. See the DIO section.
[2] Signal implemented as GPIO.
[3] Output only
[4] Input only
[5] 5 V tolerant input

RS-485

The TS-7553-V2 has a single RS-485 port that supports automatic TXEN via kernel driver features and a GPIO pin. The RS-485 kernel support allows for tuning of timing, as well as polarity of the TXEN signal. For full information on using this feature, see the RS-485 kernel documentation. See the UARTs section for the location of the RS-485 port.

USB

The board offers multiple USB 2.0 host ports as well as OTG compatible ports. An on-board USB hub breaks out the host ports to multiple places, allowing the use of various devices. There is a single external USB A port, and a single internal USB A port. The internal port is provided by a USB A jack that is mounted in such a way to lay the connected USB dongle over the PCB, allowing most dongles to be contained within the board enclosure without issue.

The board has a single exposed USB B female device socket. By default, this USB device is the USB serial interface as provided by the supervisory microcontroller; however it is possible to route this USB interface to the CPU USB OTG port and enable USB gadget usage.

Power to the USB internal and external host ports can be controlled with the LED subsystem under the LED device: /sys/class/leds/en-usb-5v/ By writing to the "brightness" file in that folder a value greater than 0, it will enable USB power, setting it to 0 will turn it off. See the DIO section of the manual for more information on this.

USB Gadget

The USB B female jack by default provides a USB serial console via the supervisory microcontroller. The board provides an internal USB mux IC that can be switched to connect the CPU USB OTG port to the USB B female jack. Once booted, the kernel can support USB gadgets allowing the unit to emulate a number of various USB devices. Below is an example to set up the USB ethernet gadget:

First, load the gadget drivers and bring the interface up:

modprobe g_ether
ifconfig usb0 192.168.0.1 up

Next, switch the USB mux so that the USB device port now connects to the CPU OTG port. Note that when this command is run, USB serial will disconnect:

echo 71 > /sys/class/gpio/export
echo high > /sys/class/gpio/gpio71/direction

At this point the board will appear to the host system as a USB ethernet device, the board will have an IP of 192.168.0.1 on the USB interface. The host PC can set an IP address in this same subnet and will be able to communicate with the board. See the linux USB gadget documentation for more information on the full set of devices that are available.

The default kernel is built with most USB gadgets built as modules. If any additional support is required, the kernel will need to be rebuilt with the options enabled.

Watchdog

The board implements a WDT inside the supervisory microcontroller. A standard kernel WDT driver is in place that feeds the WDT via the I2C bus. As soon as the kernel starts it will start the WDT and feed it on 30 second timeouts every 15 seconds. If a userspace application opens and uses the watchdog file the kernel will stop auto-feeding and the user application is now responsible for feeding the WDT. The kernel driver supports the "Magic Close" feature of the WDT. This means that a V character must be fed in to the watchdog file before the file is closed in order to disable the WDT. If this does not happen then the WDT is not stopped and it will continue it's countdown. Additionally, if the kernel is compiled with CONFIG_WATCHDOG_NOWAYOUT then the WDT can never be stopped once it is started at boot.

See the Linux WDT API documentation for more information.

WiFi

This board uses an ATWILC3000-MR110CA IEEE 802.11 b/g/n Link Controller Module With Integrated Bluetooth® 4.0. Linux provides support for this module using the wilc3000 driver.

Summary features:

IEEE 802.11 b/g/n RF/PHY/MAC SOC
IEEE 802.11 b/g/n (1x1) for up to 72 Mbps PHY rate
Single spatial stream in 2.4GHz ISM band
Integrated PA and T/R Switch Integrated Chip Antenna
Superior Sensitivity and Range via advanced PHY signal processing
Advanced Equalization and Channel Estimation
Advanced Carrier and Timing Synchronization
Wi-Fi Direct and Soft-AP support
Supports IEEE 802.11 WEP, WPA, and WPA2 Security
Supports China WAPI security
Operating temperature range of -40°C to +85°C

External Interfaces

Interface	Connector Type	Description	Reference
HD1	2 x 10 pin header		Reference
HD2	2 x 5 pin header	Com2 Header	Reference
HD4	1 x 6 pin header	Keypad Header	Reference
CN5	2 x 10 pin header	XBee Socket	Reference
P1	1 x 8 pin header		Reference
CN8	DB-9 header	UART	Reference

HD1 Pin Header

Pin Layout

Pin	Name
HD1_1	VIN
HD1_2	POE_78
HD1_3	GND
HD1_4	POE_45
HD1_5	GND
HD1_6	POE_TX
HD1_7	SPI_CS# 1
HD1_8	POE_RX
HD1_9	I2C_DAT
HD1_10	UART6 RXD [1]
HD1_11	USB Host -
HD1_12	UART6 TXD
HD1_13	USB Host +
HD1_14	I2C_CLK
HD1_15	5 V
HD1_16	5 V
HD1_17	SPI_MISO
HD1_18	SPI_MOSI
HD1_19	3.3 V
HD1_20	SPI_CLK

[1] 5V Tolerant input

HD2 COM2 Header

Pin Layout

Pin	Name
HD2_1	UART1 RS-485 +
HD2_2	UART3 RXD
HD2_3	UART3 TXD
HD2_4	CAN1_H
HD2_5	GND
HD2_6	UART1 RS-485 -
HD2_7	UART4 TXD
HD2_8	UART4 RXD
HD2_9	CAN1_L
HD2_10	NC

HD4 Keypad Header

Pin	Name
HD4_1	GND
HD4_2	Keypad 0 / DIO 117 [1]
HD4_3	Keypad 1 / DIO 118 [1]
HD4_4	Keypad 2 / DIO 119 [1]
HD4_5	Keypad 3 / DIO 120 [1]
HD4_6	GND

[1] Note that using this pin as standard DIO requires unloading the modules used by the Keypad.

CN5 XBee Socket

info

The socket is designed to support various radios from multiple vendors. Even within the same product line, e.g. Airgain's Skywire cell modems, some modules may deviate slightly from the standards set out by the manufacturers. Due to this, we recommend reviewing the datasheet carefully for any potential modules intended to be used in combination with this platform. Our support team (email or support portal) is happy to help advise with any questions on device compatibility.

The XBee socket on the TS-7553-V2 is designed to support multiple devices. In addition to the standard range of XBee products from Digi, it also supports NibeLink Skywire cellular modem modules. The TS-7553-V2 can provide 3.3 V or 4 V to the power pin of the XBee form factor, and can also support USB devices provided by compatible modules.

Power is not turned on by default and must be explicitly enabled. The 3.3 V or 5 V regulators can be enabled by manipulating the regulator enable DIO.

USB on pins 7 and 8 of the XBee socket are by default disconnected from module. This is because some older modules call out these pins with different functions or to leave as a no connect. A DIO is used to enable the USB host connection to the XBee socket. See the DIO section of the manual for more information.

The special VBUS output on pin 6 can provide different voltages based on the combination of 3.3 V and the 5 V regulator enables. VBUS is 0 V output when neither of the regulators are enabled and when only the "XBee 3.3 V" supply is enabled. VBUS is ~4.7 V output when only the "MODEM 5 V" regulator is enabled. And VBUS is 3.3 V then both "XBee 3.3 V" and "MODEM 5 V" regulators are enabled. Note that in the last case, VCC to the XBee socket will still remain at 3.3 V, and the actual 5 V regulator is disabled for safety.

Some form factor compatible modules provide a USB device on two pins of the XBee socket. In order to ensure compatibility with most modules, these USB pins are electrically disconnected by default and must be enabled. In order to enable USB on the XBee socket, assert the En. XBee USB# signal. Note that most XBee modules will not function if USB is enabled. Only enable the USB connectivity if the module used supports USB on pins 7 and 8!

This example sets up a Nimbelink Cellular modem on the XBEE header.

danger

This should not be done with 3.3V XBEE modules

# Deassert NIMBEL_PIN20 / PWR_ON#
gpioset 2 3=0

# Assert modem reset:
gpioset 2 20=0

# Enable USB to the XBEE header:
gpioset 4 7=0

# Turn off EN_XBEE_3.3V:
gpioset 0 9=0

# Turn on MODEM_5V (turns on ~4V to modem)
gpioset 0 8=1

# Take modem out of reset
gpioget 2 20 > /dev/null

# Assert PWR_ON# to turn on modem
gpioset 2 3=0
sleep .2
# Some modems need PWR_ON# to be 'pressed', so deassert again:
gpioset 2 3=1

After running either of these it should enable the USB device. See the Nimbelink documentation for your specific radio for software recommendations. Some modems use USB serial devices, and use pppd/modemmanager. Some higher speed modems may show up as USB CDC-NCM and act as a virtual usb ethernet, and others may use radio specific drivers.

This example turns on an XBEE and removes it from reset:

# Assert XBEE_RESET#
gpioset 2 20=0

# Turn off 4V
gpioset 0 8=0

# Turn on XBEE 3.3V
gpioset 0 9=1

sleep .1

# deassert XBEE_RESET# to take it out of reset:
gpioget 2 20 > /dev/null

Once out of reset, we have a test utility that can test modem presence:

wget http://ftp.embeddedTS.com/ftp/ts-arm-sbc/ts-7840-linux/samples/xbeetest.c
gcc -std=gnu99 xbeetest.c -o xbeetest
./xbeetest /dev/ttymxc7

This will output:

Module detected

XBee 802.15.4 RELEASE V 10EF, Build: Jan 16 2015 13:09:23
Hardware Version: W44I

For Xbee serial modules refer to these related links:

Pins

Zigbee Socket

Pin	Name
CN5_1	VCC [1]
CN5_2	UART7 RXD
CN5_3	UART7 TXD
CN5_4	GND
CN5_5	XBee reset# / DIO 84
CN5_6	VBUS
CN5_7	USB Host + [2]
CN5_8	USB Host - [2]
CN5_9	DIO 40
CN5_10	GND
CN5_11	GND
CN5_12	DIO 46
CN5_13	DIO 34 [3]
CN5_14	3.3 V
CN5_15	GND
CN5_16	DIO 41
CN5_17	NC
CN5_18	NC
CN5_19	NC
CN5_20	DIO 35 [4]

[1]This pin will provide 3.3 V or 4 V depending on if "XBee 3.3 V" or "MODEM 5 V" is enabled. See the DIO section for more information.
[2]Enabled with En. XBee USB#.
[3]On PCB revision D and below, this signal a no connect. This is used by some newer radios to indicate boot status, which can be read on revision E and above.
[4]On PCB revision D and below, this signal was connected to GND#. As this is needed to be controllable on new systems this was routed to a CPU GPIO on PCB revision E and above.

P1 Pin Header

Note that pin 1 is marked with a small dot on the silkscreen near the PCB edge. It is also the closest pin to the LED block. See Specifications section for power input specifications when using power input via this connector.

Pin	Name
1	Power-in VCC
2	Power-in VSS
3	UART1 RS-485 +
4	UART1 RS-485 -
5	GND
6	Relay NO
7	Relay COM
8	Relay NC

CN9 DB-9 Header

DB9 Socket

Pin	Name
1	UART1 RS-485 +
2	UART5 RXD
3	UART5 TXD
4	CAN0_H
5	GND
6	UART1 RS-485 -
7	UART5 RTS[1]
8	UART5 CTS[2]
9	CAN0_L

[1]Output only
[2]Input only

CN6 Barrel Jack

The barrel jack marked CN6 is a center-pin-positive 5.5 mm OD, 2.1 mm ID coaxial power connector. See Specifications section for power input specifications when using this.

Specifications

Power Specifications

The TS-7553-V2 accepts a range of voltages from 5 V to 28 V DC. Note that there is a dead zone around 5.4 V as this is the transition point from directly accepting 5 V input to changing over to the switching regulator that can accept up to 28 V. The full voltage range is accepted on the same set of power input pins.

Input	Min voltage	Max voltage
5 V input range	4.7	5.3
28 V input range	5.6	28

Power Consumption

Power consumption of the TS-7553-V2 can vary greatly depending on the build options, the peripherals in use, and the end application behavior. The majority of the power savings are in the automatic CPU scaling and by disabling the Ethernet PHY. Additionally, direct 5 V input is more efficient than using a higher input voltage. This is due to the fact that any input voltage above 5 V is first run through an on-board switching regulator in order to regulate it down to 5 V.

The following tests were performed on a TS-7553-V2 Rev. D PCB with the aftermarket Debian Stretch with Linux kernel 4.9 image. When the measurements were taken the USB serial console was disconnected first to ensure the most accurate measurement possible and the TS-SILO supercapacitors were not charging during the testing. The exact model used for testing is TS-7553-V2-SMW5I. Please see Power Consumption Caveats for details on how to get these power numbers.

TS-7553-V2-SMW5I

Test	Input (V)	Avg. (W)	Peak (W)
CPU idle, eth0 brought down, booted from SD card, CAN disabled	5 VDC	0.385 W	0.525 W
CPU idle, eth0 linked, booted from SD, CAN disabled	5 VDC	0.670 W	0.830 W
CPU running openssl speed, eth0 linked running iperf, booted from SD, CAN enabled	5 VDC	1.105 W	1.160 W
CPU idle, eth0 brought down, booted from SD card, CAN disabled	12 VDC	0.490 W	0.700 W
CPU idle, eth0 linked, booted from SD, CAN disabled	12 VDC	0.830 W	0.970 W
CPU running openssl speed, eth0 linked running iperf, booted from SD, CAN enabled	12 VDC	1.320 W	1.355 W

Power Consumption Caveats

In order to achieve the numbers documented above, there are some operational caveats that must be noted.

Due to the design of the Ethernet MAC/PHY of the i.MX6UL CPU and the software patterns of U-Boot and the Linux kernel, the PHY is booted to Linux in a high power state. This occurs even though Linux leaves the interface unconfigured and down. This is because U-Boot brings up the MAC and PHY devices to configure them, but leaves them on. Lower power can be achieved by bringing the interface up and then back down if the interface is not in use; the kernel puts the PHY in a low-power state when the interface is brought down. This can be done with:

ifconfig eth0 up
ifconfig eth0 down

The WILC WiFi device achieves the lowest power if either the kernel module (wilc_spi) is not loaded, or if the wlan0 interface is brought up but left unconfigured. If WiFi/BLE is not needed for an application, it is best to prevent the wilc_spi module from being loaded. If only BLE is needed in an application, the wlan0 interface needs to be brought up first and left active regardless. If WiFi is used in an application, then the driver will automatically handle power levels during operation of the interface.

Supercapacitors

Charging of the supercapacitors causes a change in overall power consumption of the whole system. Because of this, the numbers below are the average curve and peak power draw during a full charge cycle of the TS-SILO technology itself. In other words, the power noted below is separate from the numbers listed above and should be added to the numbers above to sum the total power draw of the whole device.

The current consumption of TS-SILO supercapacitors is not linear during charging. The charge process has a curve to it and the maximum average current consumption is near 80% of full capacity. Below we document the minimum and maximum average over the whole curve and the peak consumption that could be seen.

TS-SILO charging

Charging V	Min Avg. W	Max Avg. W	Peak W
5	0.85	1	1.45
12	2.7	5.3	6.3

Backup / Restore

While all of our products ship with images pre-loaded in to any supplied media, there are many situations where new images may need to be written. For example, to restore a device to its factory settings or apply a customized image/filesystem for application deployment. Additionally, specific units may be used for development and that unit's disk images need to be replicated to other units to be deployed in the field.

We offer a number of different ways to accomplish both capturing images to be written to other units, and the actual writing process itself. See the section on our USB Image Replicator tool to capture and/or write images, as well as details on manual processes to capture and write images on each of this device's media.

Installing​

Building​

Configure the build:​

Cross Compiling​

Configuring the Network​

Installing New Software​

Setting Up SSH​

Starting Software Automatically​

Features​

Battery Backed RTC​

Bluetooth​

CAN​

FlexCAN​

CPU​

GPIO​

Digital I/O (DIO)​

DIO Lines​

Special DIO​

eMMC​

Ethernet Port​

FEC PTP Support​

FRAM​

I2C​

IMU​

Accelerator/Gyro (MPU-9150)​

Reading the Accelerometer​

Reading the Gyroscope​

Reading the Magnetometer​

Accelerometer (ST ISM330)​

Gyroscope (ST ISM330)​

Magnetometer (ST IIS2MDCTR)​

Jumpers​

LCD + Keypad​

LCD​

Keypad​

LEDs​

microSD Card Interface​

Reboot Source​

Relay​

Sleep​

SPI​

Supervisory Microcontroller​

TS-SILO Supercapacitors​

U-Boot Settings​

Charge and Discharge Times​

UARTS​

RS-485​

USB​

USB Gadget​

Watchdog​

WiFi​

External Interfaces​

HD1 Pin Header​

Pin Layout​

HD2 COM2 Header​

Pin Layout​

HD4 Keypad Header​

CN5 XBee Socket​

Pins​

P1 Pin Header​

CN9 DB-9 Header​

CN6 Barrel Jack​

Specifications​

Specifications​

Power Specifications​

Power Consumption​

TS-7553-V2-SMW5I​

Power Consumption Caveats​

Supercapacitors​

TS-SILO charging​

Backup / Restore​

Installing

Building

Configure the build:

Cross Compiling

Configuring the Network

Installing New Software

Setting Up SSH

Starting Software Automatically

Features

Battery Backed RTC

Bluetooth

CAN

FlexCAN

CPU

GPIO

Digital I/O (DIO)

DIO Lines

Special DIO

eMMC

Ethernet Port

FEC PTP Support

FRAM

I2C

IMU

Accelerator/Gyro (MPU-9150)

Reading the Accelerometer

Reading the Gyroscope

Reading the Magnetometer

Accelerometer (ST ISM330)

Gyroscope (ST ISM330)

Magnetometer (ST IIS2MDCTR)

Jumpers

LCD + Keypad

LCD

Keypad

LEDs

microSD Card Interface

Reboot Source

Relay

Sleep

SPI

Supervisory Microcontroller

TS-SILO Supercapacitors

U-Boot Settings

Charge and Discharge Times

UARTS

RS-485

USB

USB Gadget

Watchdog

WiFi

External Interfaces

HD1 Pin Header

Pin Layout

HD2 COM2 Header

Pin Layout

HD4 Keypad Header

CN5 XBee Socket

Pins

P1 Pin Header

CN9 DB-9 Header

CN6 Barrel Jack

Specifications

Specifications

Power Specifications

Power Consumption

TS-7553-V2-SMW5I

Power Consumption Caveats

Supercapacitors

TS-SILO charging

Backup / Restore