can't get SPI interface to work on the orange pi zero 3

[p789]

Hi,

I am trying to get a led matrix to work via the SPI interface but cannot get it to work.

 

I have enabled the interface and have an spi-device under /dev and there is a spi-module loaded.

 

I have tried to connect MOSI and MISO to run spidev-test and everything seems to be fine but when I connect the led-matrix simply nothing happens.

 

I can run the example-scripts from the luma-matrix library without getting an error - but there is simply nothing appearing on the matrix - however it does light up when I touch it on the backside...

 

i have tried to use different values for param_spidev_spi_bus and param_spidev_spi_cs in armbianenv.txt but to no avail...

 

Does anybody have an idea what I could try?

 

many thanks!

[robertoj]

Post the model of the led-matrix and its user manual. Does it give any feedback on the SPI port? Is the example script able to detect errors?

 

Re-check all the cables

 

Try the things tried in these threads:

 

https://forum.armbian.com/topic/29657-orange-pi-zero-2-and-spi-ili9341-touchscreen-fbtft-legacy-kernel-partial-success/#comment-169775

 

https://forum.armbian.com/topic/41365-orange-pi-zero-2w-overlay-i2c-spi-help/#comment-195256

[p789]

Hi,

 

thanks for replying.

 

It is a MAX7219, the manual can be found here: https://cdn.shopify.com/s/files/1/1509/1638/files/AZ039_A_7-13_EN_B07CRF13ZQ_214c9067-2dde-4ce9-9f90-943eb3046e57.pdf?v=1721043187

 

The module does not show any reaction to scripts that run without errors. The scripts however do report errors when eg I use the wrong device.

 

When I touch the backside of the led-matrix it lights up, so it seems my fingers simulate somehow data incoming that it does not seem to get otherwise.

 

I don't understand the SPI interface very well but could it be that there is something wrong with the cs-signal, so that the pi sends out data but the matrix thinks another slave would be the recipient?

 

Could it be an issue with a device tree overlay?

 

And in armbian-config I have a choice of spidev_0_0, spidev_1_0, spidev_1_1, spidev_1_2 and spi_spidev....

 

What is here the proper selection?

Edited August 2 by p789

[p789]

I now have tried the led-matrix with an arduino and it works perfectly.

 

So the problem seems indeed to be on the armbian-side.

Any suggestions on how to proceed?