DAC8775 Quad-Channel DAC EVM - unlicensed roadtest part -1: Raw SPI

RE: DAC8775 Quad-Channel DAC EVM - unlicensed roadtest part -1: Raw SPI

Jan Cumps — Fri, 13 Jul 2018 21:05:58 GMT

It's not easy ... There's two way communication between my controller and the DAC, but no meaningful conversation.

I first tried to set all registers as I think they should be set, but can't get the DAC to output a voltage or current.

Then I tried the debug sequence. The DAC has a toggle bit. You set a user bit in one register. That toggles another user bit in another register. You can read that back.

That doesn't work with my current setup.

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I'll try a new setup, using a microcontroller that I know well instead of the Bus Pirate as SPI master.

I'll have to write a small SPI firmware program but that should be doable. Hang on ...

RE: DAC8775 Quad-Channel DAC EVM - unlicensed roadtest part -1: Raw SPI

jw0752 — Wed, 11 Jul 2018 22:01:07 GMT

One man's trash is another's treasure. It is good that you and DAB were able to trade so that we could enjoy your exploration of this board.

John

RE: DAC8775 Quad-Channel DAC EVM - unlicensed roadtest part -1: Raw SPI

genebren — Wed, 11 Jul 2018 21:41:24 GMT

Great unlicensed roadtest review. I really enjoy how you dig into things and try interesting approaches and tools to get your data. Good luck as you move forward on this review.

Gene