I am using the SPI0 bus (using SPIDEV) for an application and want to use the P9_12 as an additional chip select in the Beagle Bone Black Wireless. I have changed the universal-cape-00A0.dts file to include an option to configure p9.12 as spi_cs. However, whenever I want to run the program the pin does not work as a chip select.
The highlighted items in the table you shared are the pins set up for SPI1, however, I need to use SPI0 which is in pins P9.17, P9.18, P9.21, and P9.22.
According to other forums one can set gpios as an “spi_cs” in SPI0 to have additional slaves. I want to understand how to that.
This approach did not work for me. Is there a specific file that one has to use? Or does any file work?
I compiled it and moved the dtbo file to the /lib/firmware folder and rebooted the system. Is this what had to be done?
I have also added it to the uEnv.tct file and it did not work.
Can I use p9.17 at the same time I am using other Chip selects? (I’ve read that you should not use p9.17 if you are using other chip selects, just wanted to confirm)
I am using SPI0 which are the pins P9.17, P9.18, P9.21, and p9.22.
I want an additional chip select pin using P9.12. If P9.17 cannot be used at the same time as using gpios chip selects then I am looking to use P9.15 as chip select.
Lianne, did you ever find a solution to this?
I’m now also trying to set up an extra CS pin on SPI (SPI1 instead of SPI0 unlike you) and I haven’t been successful with Robert’s instructions here.
I wonder if there’s any way to check that the device tree overlay worked as expected? I.e., if I use pin-config -l <my pin> should I expect to see SPI as an option?