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Use raspberry pi 4 GPIO with node js

I recently tried to use the GPIO of my Raspberry pi 4 with node js. I managed to get the program to work on my raspberry, but as soon as I wanted to put it on another raspberry, I was no longer able to make it work.

For this, I use the onoff library. The program is as follows:

var GPIO = require('onoff').Gpio;

var lightPin = new GPIO(23, 'out');

lightPin.writeSync(1)

But as soon as I run it, I get the following error:

node:internal/fs/utils:353
    throw err;
    ^

Error: EINVAL: invalid argument, write
    at Object.writeSync (node:fs:939:3)
    at Object.writeFileSync (node:fs:2355:26)
    at exportGpio (/home/pi4b/API/node_modules/onoff/onoff.js:18:8)
    at new Gpio (/home/pi4b/API/node_modules/onoff/onoff.js:172:36)
    at Object.<anonymous> (/home/pi4b/API/helper.js:3:16)
    at Module._compile (node:internal/modules/cjs/loader:1369:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1427:10)
    at Module.load (node:internal/modules/cjs/loader:1201:32)
    at Module._load (node:internal/modules/cjs/loader:1017:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:122:12) {
  errno: -22,
  syscall: 'write',
  code: 'EINVAL'
}

Node.js v21.0.0

Version of node.js -> 21.0.0 (the same for both pi)

Version of npm -> 10.5.0 (the same for both pi)

Version of onoff -> onoff@6.0.3 (the same for both pi)

Debian version -> 12.5 (against 11.9 for the old pi)

For information, the node_modules folder was completely deleted and reinstalled with npm i. I also tried with the library RPi.GPIO in python which seemed to work correctly.

Thank you for your help.

Solution

  • It seems that Raspberry OS kernel addresses GPIO pins yet by another numbering scheme.

    ~ $ cat /sys/kernel/debug/gpio
gpiochip0: GPIOs 512-569, parent: platform/fe200000.gpio, pinctrl-bcm2711:
...
 gpio-532 (GPIO20              |sysfs               ) in  lo
 gpio-533 (GPIO21              |sysfs               ) in  lo
 gpio-534 (GPIO22              |sysfs               ) in  lo
 gpio-535 (GPIO23              )
 gpio-536 (GPIO24              )
 gpio-537 (GPIO25              )
 gpio-538 (GPIO26              |sysfs               ) in  lo
...

    If you want to address the GPIO23 pin, you must use the number after gpio-[number]

    In your case:

    var GPIO = require('onoff').Gpio;
var lightPin = new GPIO(535, 'out');
lightPin.writeSync(1)