Marry Xmas to all :slight_smile: I've installed and tried today this mcp23017chip node , but it says: TypeError: Cannot read property 'setBit' of null How can I debug it further, what could be the problem? Can I see somewhere the source-code of this node? My guess is: it can only handle the de…

[image] PizzaProgram: Can I see somewhere the source-code of this node? go to the .node-red folder then fo to the node_modules folder in there you should see a folder for the node and its's code.

@zenofmud Thanks :slight_smile: found it here: /home/openhabian/.node-red/node_modules/node-red-contrib-mcp23017chip Also found this... : changing "i2c-bus": "~1.2.2" to "i2c-bus": "~5.2.1" and installing it locally via npm i /path/to/mcp23017chip did the thing. All is working good now It's …

[image] PizzaProgram: How do I apply changes? enough to restart NR? edit the file, apply the change, save the file, stop NR, start NR test

Thanks :slight_smile: I've hoped it will be so easy. But now I have no idea, how to find out, what is the "right bus number"? i2c-11 is not similar to : "~5.2.1" :~$ sudo i2cdetect -l i2c-11 i2c i2c-tiny-usb at bus 001 device 013 I2C adapter :~$ sudo i2cdetect -y 11 0 1…

"dependencies": { "i2c-bus": "~5.2.1" }, Hmmm... that number seems to be rather the current "NPM i2c-bus modul" 's version number: [image] i2c-bus I2C serial bus access with Node.js

Try sudo i2cdetect -y 1 If you look at what you posted :~$ sudo i2cdetect -l i2c-11 i2c i2c-tiny-usb at bus 001 device 013 I2C adapter it shows the bus is 001. As for "i2c-bus": "~5.2.1" ~version “Approximately equivalent to version” , will update you to all future patch …

[image] zenofmud: it shows the bus is 001. No. You mix USB bus with I2C bus. For proof, look at 1 line under it: :~$ sudo i2cdetect -y 11 11 is the bus number of that command. It is successfully listing both devices under 0x27 and 0x51. I've already found the problem: At mcp23017chip.js …

[image] PizzaProgram: I've already found the problem I suggest you try to contact the author of the node or possibly try one of the other i2c nodes.

@willhey I've successfully enhanced the component to accept Bus number for each chip. [kép] It can be downloaded from here... I can see the device on Bus 11, but the node reports back: Error: Invalid I2C bus number 11 [kép] I have now idea what could be wrong. It should work. Somebody have…

Are you running as root ? You run i2cdetect as root so I suspect you may need this to match

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zenofmud 25 December 2020 09:49 4

edit the file,
apply the change,
save the file,
stop NR,
start NR
test

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