Pi4/Pi400/Trixie attempt

mick bell

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Dec 3, 2025, 11:22:38 AM12/3/25

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About to move my BCM2835 program from Bullseye to Trixie as I suspect my SD card is failing. The configure/make/check/install all seemed to work ok.

Recompiling my stuff will take a bit longer as I was halfway through making some major changes on GThreads and other involved bit (unrelated to BCM2835 code).

I build on a Pi400, and deploy on a Pi4B.

I will report back on progress ......

mike james

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Dec 3, 2025, 1:00:34 PM12/3/25

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I'd be interested to hear if there is a problem or not - but on

past upgrade experience the only problems I have encountered are permissions.

mikej

Colin Bate

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Jan 4, 2026, 12:47:57 PMJan 4

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I've also had to rebuild my development RPi4B due to SD card failure so I too used Trixie and the latest v1.77 of the BCM2835 library.

Installation of the BCM2835 library was straight forward, no issues, built a test program to access the Waveshare High Precision HAT (https://www.waveshare.com/wiki/High-Precision_AD_HAT) with the BCM2835 library.

Program ran and accessed the ADS1263 chip via SPI and retrieved voltage data from the ADS, all good.

Only issue was I needed to run the test program as root.

So next task is to see if I can run as non root user via the libcap method mentioned in the BCM2835 documentation.
CB

Colin Bate

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Jan 10, 2026, 6:32:46 AMJan 10

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An update to using the BCM2835 library with Trixie on RPi4B. I have now been able to run my test program that uses SPI without using sudo.

I followed the instructions for installing libcap library on the BCM2835 page (https://www.airspayce.com/mikem/bcm2835/index.html), also note, need to add -lcap to build args for my program.

The only issue I have now is I'm not able to debug my program as the program fails when calling SPI init, (just as it does if not sudo), but running in the terminal windows works just fine without sudo.

I'm running VS Code on my win11 PC and editing/building/debugging the code on my RPi4 via ssh.

This one has stumped me. I've setup VC Code launch.json & tasks.json to build/run setcap (via script)/and debug in one step, and also individually, but when debugging it it always fails with 'SPI init failed' and terminates.