SAADC is not scanning

RE: SAADC is not scanning

Jørgen Holmefjord — Tue, 24 Jan 2017 10:16:57 GMT

Can you try this example, to see if scan mode is working?

RE: SAADC is not scanning

tkorsdal — Mon, 23 Jan 2017 07:45:26 GMT

Marking on the device used is QFAABA 1543AF

I tried on a DK board marked "PC10040 V1.1.1 2016.43" device marked QFAAB0 1608AD, FICR.PART = 0x00052832 FPIC.VARIANT=0x41414230. It has the same problem.

Please advice.

RE: SAADC is not scanning

Jørgen Holmefjord — Fri, 20 Jan 2017 14:38:06 GMT

What is the markings on your chip? I would not recommend using any of the Engineering variants. The nRF52 DK have been shipped with Revision 1 chips for a long time.

RE: SAADC is not scanning

tkorsdal — Fri, 20 Jan 2017 14:06:13 GMT

My DK revision os PCA10040 0.9.0 - from the compatibility matrices (great documents btw.!) I conclude I need to update to at least 1.0.0 (although in the matrix 0.9.0 is supposed to use Engineering revision B which does NOT include errata 28).

RE: SAADC is not scanning

tkorsdal — Fri, 20 Jan 2017 13:25:47 GMT

Local SAADC SAMPLERATE timer can not be used in SCAN mode.

RE: SAADC is not scanning

tkorsdal — Fri, 20 Jan 2017 13:07:14 GMT

In the IRQ handling of SAADC_EVENTS_STARTED I have this peculiar code snip:

// We only want to handle start event the first time
SAADC_INTENCLR = INT_STARTED;

It is a mistake of course - I need the start event on every scan. But for some reason these two lines does NOT stop the SAADC_EVENTS_STARTED. And from debugging the buffer handling (shifting between dma_sample_buffer 0 and 1 works fine.

RE: SAADC is not scanning

tkorsdal — Fri, 20 Jan 2017 11:14:08 GMT

I have noticed the errata on the calibration->start issue. But in the code posted here I have skipped calibratiion.