i2c

i2c python sample

Sample program to demonstrate I2C connection between Arduino Uno and Atlas 200 DK board using the python-periphery python library.

Prerequisites

• Atlas 200 DK board, PCB type IT21DMDA
• Arduino Uno R3

Setup

• The Atlas board is the master and connects to the Arduino slave
• Connect Atlas board I2C2-SDA (pin 3) to Arduino SDA.
• Connect Atlas board I2C2-SCL (pin 5) to Arduino SCL.
• Connect Atlas GND to Arduino GND.
• On the Atlas board, as the root user, edit the /etc/rc.local file and insert the following commands before exit0. Then restart the board. This will set the appropriate permissions need to run the samples.

echo 504 >/sys/class/gpio/export
echo 444 >/sys/class/gpio/export
chown -R HwHiAiUser /sys/class/gpio/gpio444
chown -R HwHiAiUser /sys/class/gpio/gpio504
chown -R HwHiAiUser /sys/class/gpio/gpio444/direction
chown -R HwHiAiUser /sys/class/gpio/gpio504/direction
chown -R HwHiAiUser /sys/class/gpio/gpio444/value
chown -R HwHiAiUser /sys/class/gpio/gpio504/value
chown -R HwHiAiUser /dev/i2c-1
chown -R HwHiAiUser /dev/i2c-2
chown -R HwHiAiUser /dev/ttyAMA0
chown -R HwHiAiUser /dev/ttyAMA1
usermod -aG HwHiAiUser HwHiAiUser

Run

1. Upload sketch.ino to Arduino Uno board. Open the serial monitor.
2. On the Atlas board, run python3 i2c.py. If the connection works, you will see "Hello from Atlas" on the Arduino serial monitor, and the following output on the Atlas board terminal:

i2c connection test
Write to I2C
Read from I2C: Hello from Arduino