Teensy3.6 NRF24L01 ST7735

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Zee

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I'm wanting to use a 1.8" 128x160 RGB TFT_LCD (ST7735) and NRF24L01 wireless module driven from a t3.6. My question is are there any libraries available to do this or am I trying to do something that takes an engineer? If I use pin 10 for the display CS what pin should I use for the NRF chip select? I've been able to get the display to work and is impressively fast.
 
After further investigation, I see why this is question doesn't have any replies. Must be rocket science. :)
 
Must be rocket science
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I'm no SPI expert but I do know it can be problematic to get multiple SPI devices to play nice on the same bus, especially SD cards. You can use any pin you want for the NRF24L01 CS since that is assigned for each device by you. Some libraries might make fixed assumptions about the pins, there I think you'd need to over-ride (edit) the library default.

The important unknown at this point is this: Do both devices use the same SPI speed, bit order and mode? If they do, you have to make sure that both libraries release the MISO line so the other device can communicate. It might be simple if the ST7735 is write only, it never is read. It might be, don't know for sure.

If the devices use different format SPI parameters, then the libraries each need to implement the SPI beginTransaction and endTransaction methods to ensure they release the MOSI line. An example is here:

https://www.pjrc.com/teensy/td_libs_SPI.html

Finally, the 3.6 the hardware supports multiple hardware based SPI buses. What I don't know is how the heck you make use of them. There is more on that here (and a specific mention of the ST7735):

SPI-Busses-0-1-2

HTH

Edit: The multiple hardware buses appear to be supported in the Teensy specific SPI library code. It would be great if an example program (or two) were included to demonstrate the additional Teensy features (rather than the generic Arduino sketches, making it look like just another SPI library).
 
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