Russell wrote; >could you perhaps share an outline of the "fine print" which was pertinent >and any tricks which you discovered along the way. My basic mistake was that the opcode for loadcfg0 & loadcfg1 has a "don't care" bit in it which I left as a 0. What I didn't notice for a while was that this particular bit is the power-up bit so every time I set the configuration words, I was powering the device down and hence it did appear to be not doing much at all audio-wise! Arghhh... The data sheet assumes that you want to use it in a mobile phone so you have to carefully trace the audio paths that you need versus the ones that they give in the examples. I made up constants (#define's) for all the config word bits (all 32 of them) to keep the code a bit more readable than just loading 4 bytes with values. If you start with both the config words cleared, then set any bits you need it works out easier. The timing diagrams are backwards (compared to NS ones) so the first byte to send (shown as byte 3 BTW) is on the RHS of diagram. Just send the data LSB first & remember to set SS high between the instructions. (but leave low during a 3 byte instruction) It's got several audio inputs & outputs so you need to plan out what you want to use. Hope this helps anyone who's interested in this neat chip. Regards...