Rewritten i2c_slave

[IgorLopez]

Hi,

I did never get the i2c_slave function in the i2c_lib 3.1.1 to work so I rewrote it.
My version does not handle repeated starts and has only been tested on real HW (with a reaspberry PI as master) for reading/writing one byte.
I did a lot of debugging and testing using the simulator and a plugin I wrote to act as master.

Since I am convinced (95 % at least) that the current i2c_slave is buggy I hope that you will fix it in coming releases and I am attaching my version if that would help.

This version contains a minor artefact on the SDA when doing the ack for correct address in that it takes almost 1 us before the SDA is pulled low which means that the SDA pin is high for almost 1 us before being pulled down by slave before bit 9. No problem for normal 100 kKz clock but will be tight for a 400 kHz clock.

/Igor

[Thomas]

The lib_i2c was updated to version 3.1.4 in the meantime.
You can try that version to see if it fixes the problem.