Ch32x03x i2c sensor example

[unicab369]

this one was tough, but I learn a lot about I2C.

[kuwoyuki]

return 0x11; // what does this mean? 
return 0x12; // nobody knows
return 0x13; // it's a mystery!

[cnlohr]

@unicab369 you have to add a README.md to each of these to explain:

1. How to wire it up
2. What it should be connected to
3. What the registers that are implemented mean
4. What address the slave is at.

Someone who sees this needs to know how to just use it.

[cnlohr]

@unicab369 please switch to the other timer mechanism.

[unicab369]

ok, I think it's fixed.

[cnlohr]

Yes, but you now brought in the uart demo that has the stuff we don't want in it timer wise.

[cnlohr]

[unicab369]

@cnlohr sorry, I got my branches mixed up. can we resolve the UART stuff first, then look at this one.

[cnlohr]

You will need to rebase this branch because of the conflicts. See the message below.

[cnlohr]

This file does not belong in this merge!

[cnlohr]

@unicab369 you still included the uart stuff in this mege request. Please remove it.

[unicab369]

@cnlohr how does it look now? I move the i2c into a lib bc it should also works with V10x, v20x, and v30x.