I've got a problem with the A/D readings on a board with a '2407.The problem is that the readings on all the channels are low. I put in 3.28v on the a/d input pins and I read back 0x3B5 +/- a few counts. I would expect the reading to be close 0x3FF I've replaced the DSP thinking it was bad, but no luck fixing the problem. I've verified all the voltages to the DSP a/d power pins are solid. It's almost as if the Calibration register is set with a value and it's changing the reading (Calibration is not implemented in this DSP according to Ti). If I try to read the Calibration register from CC, it say's it's an invalid address.
Any ideas would be appreciated.
Thanks.