Multi-SPI devices on same bus, different CS of course - HELP

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Moderator: Mmiscool

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Re: Multi-SPI devices on same bus, different CS of course -

By Ecoli-557
- Tue Aug 23, 2016 7:56 am #53659 Thanks for the reply. I am using GPIO12-15; CS for the TFT on GPIO15 and the CS for the 23S17 on GPIO4 or 5 - they both did the same thing which also leads me to believe something is going on with multiple SPI slaves on the same bus - even though you have different CS for the devices.
SPI is faster, full-duplex and has never caused me a problem on other procs, which is why its a little frustrating for me at this point.
I have reached out to Mike in an effort to have him look through the lib to see if there is a problem as I am more experienced at assembler or one step above. These other layers between me and the hardware blurs what is happening with the hardware <grin>.

Any other thoughts?
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Re: Multi-SPI devices on same bus, different CS of course -

By Ecoli-557
- Tue Aug 23, 2016 10:17 am #53663 Upon further testing, I found that the SPI port expander AND the TFT display will work together (at least not lockup) as long as I do not actually send a tft.print command to the TFT.
I am not certain what this means because sending tft.text.color and tft.text.cursor commands seem to taken just fine.

Anybody out there with more experience with this??
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Re: Multi-SPI devices on same bus, different CS of course -

By Mmiscool
- Tue Aug 23, 2016 10:39 am #53664 It would seem that any thing that is activly redrawing an eliment on the screen will cause the issue. So long as you avoid the tft commands while doing other spi stuff should be fine. . .
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Re: Multi-SPI devices on same bus, different CS of course -

By Ecoli-557
- Tue Aug 23, 2016 10:43 am #53665 Thanks Mike. I think I need both in the same loop, but, as an experiment (who doesn't like to experiment?), I will remove the 3 lines pertaining to the 23S17 and see what that does.
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