Re: Weak SPI output on Lolin NodeMCU V3
Posted:
Fri Aug 19, 2016 3:27 am
by danbicks
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
Re: Weak SPI output on Lolin NodeMCU V3
Posted:
Fri Aug 19, 2016 5:52 pm
by tcpipchip
I having the same problem! ;(
Re: Weak SPI output on Lolin NodeMCU V3
Posted:
Sun Aug 28, 2016 4:40 pm
by Ecoli-557
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.
Re: Weak SPI output on Lolin NodeMCU V3
Posted:
Wed Aug 31, 2016 8:50 am
by Ecoli-557
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#p54175Hope this helps.
Regards to All.