I've finally sat down and started looking at getting the DAB module I got a while ago to work. I figure I'll write the control code for it on my desktop machine and then think about porting it over to the empeg.

I intend to blow a PIC to do the actual serial->i2c stuff in the finished product, but given my lack of experience in this exact field I thought I should dispense with as many variables as I can. So, the plan is to use a parallel->i2c adaptor and the i2c-parport-light kernel module with a simple PCF8574 to switch some lights on and off first. Then think about attaching my precious DAB module to the adaptor and then finally blow a PIC to control it directly.

Well, I appear to have stumbled at the first hurdle. I've built the adaptor that is shown in the i2c-parport module documentation. It was an ASCII art drawing, this is it after I fed it into Eagle:



According to the documentation it's an ELV adaptor so I modprobe it with type=3. I've connected up the PCF chip to the SCL and SDA lines and given it power and a couple of LEDs, I've also ensured the address lines are connected to GND. The modprobe appears to be sucessfull, I get a new i2c bus in my dev directory (i2c-3). But sadly all attempts to get or set any data (using i2cdump and i2cset) result in a Remote I/O Error after a long pause. Could anyone help me out?