Hi,
I am trying to use the SPI of this PGA 116 chip and using 18f4550 processor.
I did not design or create the board, I'm just the software guy who has to make it work now.
From the data sheet (p27 table 4), it looks like I can select a channel and gain in the WRITE command
but not in the READ command as the data sheet shows I have to send a byte of zero's followed
by 0x7A. I guess (don't know) I have to issue the READ (0x7A00) and then I will get a byte indicating some channel
with data. Then I don't know if I have to keep reading to get all 10 channels or do I have to issue the READ
command for each channel???
I tried to run some code where I selected the chip (low) , send (SPI write) the READ cmd , set chip (high), then
chip (low), do read but I only get 0xFFFF responses. There could be a variety issues to sort through but I guess
while I'm trying to debug this and work with the electrical guy, I was hoping someone could at least let me know
how the READ command should work. For example, is there a way to specify which channel to read? To me, the
data sheet seems kind of incomplete in describing the protocol in terms of software. Thanks!!