Hi,
I have a project involving several ADS7828 chips. We're using PIC32 MCU as master.
We have 1 ADC chip connected via BUS2, and 3 ADC chips using BUS1. The BUS2 chip
seems to communicate ok. The only issue is that supposedly unused channels also
return some fairly high vales (around 3000 counts). For the meantime, I'm just ignoring these
channels since they're not used yet.
On the other hand, all BUS1 devices don't seem to work. I get the max value on all channels
on all devices. They also don't respond when we vary the voltage on the input pins.
Here's a scope capture for a BUS1 device:
From the image above, it seems like the device is not acknowledging the bytes received from
the master.
Here's a scope capture of the device on BUS2:
The code sequence for BUS1 and BUS2 I2C communication with ADC is identical, so I'm
not inclined to think it's a bug on the code.
We're using 5V on Vdd, single-ended configuration.
Hopefully you can help me on this.