Python Programming using MRAA (gpio_blink)

Python Programming using MRAA (gpio_blink)

1. Targeted Hardware

SOM Version: PICM-001-A1

CB : RuggedBoard-A5D2X

CB Version : RB-A5D2X-V1.1

1. Targeted Software

BSP-Yocto-A5D2X 2019-03-13

• AT91Bootstrap-3.8.12

• Linux Kernel v4.9.151

• uboot-2018-07

• Yocto 2.5.2 (sumo HEAD commit 623b77885051)

Description

• Here is the simplest OnBoard-Gpio's program in mraa,to toggle three GPIO pins – 61,62,63

Required Hardware

• a5d2x-rugged board

• USB cable

Step-by-step guide

• Connect the Rugged board to your system

• Boot the board with SD card/NOR.

• Copy the below python file to data directory of rugged board through tftp protocol.

Test On-board LEDs – gpio_blink.py

• Open gpio_blinky.py program given below in your board terminal.

• Open the gpio_blinky.py program in /data directory.

PROGRAM: gpio_blinky.py

import mraa import time gpio_1 = mraa.Gpio(61) # set gpio 61 to output gpio_2 = mraa.Gpio(62) # initialise gpio 62 (D4 – Ref: Schematic) gpio_3 = mraa.Gpio(63) # initialise gpio 63 (D17) gpio_1.dir(mraa.DIR_OUT) gpio_2.dir(mraa.DIR_OUT) gpio_3.dir(mraa.DIR_OUT) while True: gpio_1.write(1) gpio_2.write(0) gpio_3.write(1) time.sleep(1) gpio_1.write(0) gpio_2.write(1) gpio_3.write(0) time.sleep(1) gpio_1.write(0) gpio_2.write(0) gpio_3.write(1) time.sleep(1)

Execution :

• Run the above code with below command in rugged board.

root@ruggedboard-a5d2x:/data# python3 gpio_blinky.py

Expected Output:

root@ruggedboard:/data# python3 gpio_blink.py libmraa[145]: libmraa version v2.0.0 initialised by user 'root' with EUID 0 libmraa[145]: gpio: platform doesn't support chardev, falling back to sysfs libmraa[145]: libmraa initialised for platform 'Atmel SAMA5' of type 20 gpio 77 gpio pin 77 gpio 81 gpio pin 81 gpio 83 gpio pin 83 ( NOTE: Toogling of LED's can be seen on the ruggedboard a5d2x).