Use this forum to chat about hardware specific topics for the ESP8266 (peripherals, memory, clocks, JTAG, programming)

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By danbicks
#53272 I was always made aware that the max SPI speed is 40MHZ, unless this has changed somewhere I thought this was always the case for the ESP8266. The clock frequency is obviously different, normally you will define SPI speed in your code with the following: SPI.setFrequency(400000);

Please let me know your findings here, Marty would be a good person to clarify this point.

Dans
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By Ecoli-557
#54017 I never thought to check my levels due to my logic analyzer (I thought) was picking up signals just fine. However, When I checked with a scope - damn! It was a 1 volt clock - clearly not good.
I did have a TFT screen working with its touch component working - then it suddenly didn't work.
Nothing I have done will make it work again - and thanks to this thread, I think I know why......

Running the NODE with 5v @ Vin doesn't help either. I think this is the problem with me trying to run several devices on the same SPI bus......

This must be a much larger problem unless there aren't too many of us working in SPI??

Regards.
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By Ecoli-557
#54176 I think I found out what was happening - the capacitance of the breadboards are wrecking the signals. See my other post on this: viewtopic.php?f=45&t=11446&p=54175#p54175

Hope this helps.
Regards to All.