I had made my own PCB with ADAS1000 on board, schematic as below.
I believe the schematic is exactly the same as the evaluation board of ADAS1000 (ADAS1000SDZ).
In order to still use ADI's evaluation environment for debug, I had reserved the same J2 connector on ADAS1000SDZ (see above schematic) on my PCB, so I can connect my PCB directly to SDP board and use the evaluation software for debugging. I had also moved the I2C EEROM(U7) from ADAS1000SDZ to my PCB(U8).
But it seems there is something wrong on SPI interface communication.
- Phenomenon 1 : board power on, set GPIO3 to "High Value", the corresponding test point(TP6) goes from low to high correctly. But after this successful trial, GPIO3 stops responding whatever I set it to low or high. It seems I can only set GPIO3 upon power up for only one time.
- Phenomenon 2 : power on and press "ReSync Write Reg", seems correct register values can be read from ADAS1000.
Then I write "FFFFFF" into the first register "ECGCTL WR", press "Write Read Reg", then press "ReSync Write Reg" again, the read value goes back to "000000" so it seems the "FFFFFF" did not correctly been written into ADAS1000 (?).
- Phenomenon 3 : try to read test tone but nothing can be read, setting as below figure
I had check the power rails(IOVDD/AVDD/ADCVDD/DVDD) and 8.192MHz clock input, nothing abnormal. Also I had measured the SPI signals as below, I can't find anything wrong among the waveform.
(yellow : CS / pink : CLK / blue : MOSI / green : MISO)
We have stocked on this problem for a long time... do you have any suggestion on this ? Very appreciated for your help.