Technologic Systems TS-7100 Series, Manual

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2/11/2020 TS-7100 - Technologic Systems Manuals
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if ( frame. data [ 0 ] == 0x4 )
printf ( "RPM at %d of 255 \n " , frame. data [ 3 ]) ;
return 0 ;
}
See the Kernel's CAN documentation here (https://www.kernel.org/doc/Documentation/networking/can.txt) . Other
languages have bindings to access CAN such as Python using C-types (https://bitbucket.org/hardbyte/python-can) ,
Java using JNI (https://github.com/entropia/libsocket-can-java) .
10.5 CPU
This device uses the i.MX6UL CPU running at 528MHz or 696MHz using a Cortex-A7 core targeting low power
consumption.
Refer to NXP's documentation (http://www.nxp.com/products/microcontrollers-and-processors/arm-
processors/i.mx-applications-processors/i.mx-6-processors/i.mx6qp/i.mx-6ultralite-processor-low-power-secure-
arm-cortex-a7-core:i.MX6UL) for more detailed information on the CPU.
10.6 GPIO
Note:
This section is incomplete at this time.
The i.MX6UL CPU and FPGA GPIO are exposed using a kernel character device. This interface provides a set of
files and directories for interacting with GPIO which can be used from any language that interact with special files
in linux using ioctl() or similar. For our platforms, we pre-install the "libgpiod" library and binaries. Documentation
on these tools can be found here (https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git/tree/README) . This
section only covers using these userspace tools and does not provide guidance on using the libgpiod library in end
applications. Please see the libgpiod documentation for this purpose.
A user with suitable permissions to read and write /dev/gpiochip* files can immediately interact with GPIO pins.
For example, to see if input power has failed:
gpioget 4 0
Multiple pins in the same chip can be read simultaneously by passing multiple pin numbers separated by spaces.
To write to a pin, the 'gpioset' command is used. For example, to set Relay 1:
gpioset 4 4=1
Multiple pins in the same chip can be set simultaneously by passing multiple pin=value pairs separated by spaces.
If a call with 'gpioset' or 'gpioget' fails with "Device or resource busy," that means that specific GPIO is claimed by
another device. The command 'cat /sys/kernel/debug/gpio' can be used to get a list of all of the system GPIO and
what has claimed them.