Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A10 => Topic started by: charlieholimex on August 18, 2016, 03:32:14 AM

Title: A10 LIME I2c
Post by: charlieholimex on August 18, 2016, 03:32:14 AM
I am trying to get i2c working on A10 LIME with the official Debian image.

I have an oscilloscope connected to GPIO 1 pins 34 and 36, looking for activity.

I have /dev/i2c-0 through 3

I have four sym links inside /sys/class/i2c-dev, e.g.
lrwxrwxrwx  1 root root 0 Aug 17 17:25 i2c-1 -> ../../devices/platform/sunxi-i2c.1/i2c-1/i2c-dev/i2c-1

I see no activity on the scope when I do
i2cdetect -y 0
i2cdetect -y 1
i2cdetect -y 2
i2cdetect -y 3

I would expect to see at least a burst on SCK when I do one of those (in this case, i2cdetect -y 1)

I have tried modprobe i2c-dev

At this point, I am ignoring the i2c device I am trying to connect, merely looking for a burst on sck.

I have tried writing a little python program using smbus, and using pyA10Lime i2c. Each of those produce Error 70 Communication Error, and no burst on the scope.

What steps am I missing?
Title: Re: A10 LIME I2c
Post by: Stanimir5F on September 05, 2016, 09:14:32 AM
Hi, Charlie!

Here (https://github.com/OLIMEX/OLINUXINO/tree/master/SOFTWARE/A10/A10-OLinuXino-LIME%20with%20MOD-IO2) you can see a simple I2C demo for A10-OLinuXino-LIME and MOD-IO2 with both program and using I2C tools. But since in the demo I use A10-OLinuXino-LIME-UEXT to connect the module to the host board I2C-2 is used (GPIO1, pins 30 (PB21) and 32 (PB20)). In the README.md you can see more details.

Stan, Olimex