Hello Friends. I have a question about the ISD1700 series of voice record / playback chips, under SPI control. I have obtained a demo board of the ISD1730 from Nuvotron and am driving it with an Arduino Uno. I am able to make this board do all the basic functions, such as play, stop, reset, power-up, volume up or down, etc. I have no issues talking with the chip, except for one...
First of all, in regular pushbutton mode, I can record a message using the on-board microphone. I can play it back with no problem. I can play it back through SPI comands, adjusting the volume as needed, via SPI. I know how to talk to the APC registers OK. Board works great, sounds pretty good.
The problem is, when I configure the analog path (APC) with SPI to use the internal microphone, I get nowhere. It is recording, but it is evidently listening to the ANA-IN pin, not the microphone. Tried every way I possibly could, just in case there was a typo on the datasheet. It simply will not pass audio from the microphone in SPI mode. It only records silence from the ANA IN.
Can someone please prove me wrong on this? Please respond if you have successfully done it. Again, I can talk to the chip fine, I just need to know if ANYONE has ever got it to work, despite the data sheet saying it should. That's all I really need, in case I'm just wasting my time. The designer guide shows a suggested schematic for using it in SPI mode, and they do not show a microphone connected.