BBBNames Pin Mapping

[Christopher Stack]

Just got started using the library, and it looks very useful! But I'm having a little trouble wrapping my head around how the BBBNames structure works.

For example, I'm trying to do some work on SPI1. I was able to write a quick demo program that worked on SPI1_0. But if I try to use the second CS SPI1_1_CS it doesn't toggle. I'm trying to use the spi1_cs1 on P9_42 but my guess is that BBBNames is mapped to P9_19. Is that right? And if so is there any way I can change it? I know the alternative is to use P9_42 as a GPIO chip select instead, but I need to wrap my head around how BBBNames work anyway.

Thanks,

Chris

[Datenheld]

Hi Christopher,

SPI is a kinda hard topic and I do not recall exactly what the problem with the chip selects was, I think that it is up to your device tree overlay to specify the correct cs and you cannot use multiple hardware cs simultaenously.

However, the SPI of libbulldog allows you have "manual" chip select lines, which are then ordinary GPIOs (which, of course, need to be free and not utilized by any other internal feature).

See http://libbulldog.org/bulldog/examples/spi/

Just create some DigitalOutputs for your chipselects and you are fine.