access serial port from node-red alongside of mptcprouter

[doryphoreanonyme]

Hello,

this post is a following of this one: #2255

I installed node-red alongside openmtcprouter which is openwrt based.

PACKAGE: openmptcprouter
VERSION: v0.58.5
TARGET: rpi4
ARCH: aarch64_cortex-a72

The goal is to add automation on a systeme which shares a couple of 4G modems for video transmitting.

It works, and for thoses interessed on doing so there is the way on openwrt:

1: update packages
opkg update
2: install node
opkg install node-npm
3: install node-red:
npm install -g --unsafe-perm node-red

However, i could't find precompiled packages rpi GPIO for openwrt.

As i would like to access hardware, i tried to use an arduino with it's usb/serial, but it doesn't work easeliy. I can not list the port in node-red and if i write it that way /dev/ttyACM0/ it throws a segmentation fault and crash node-red.

however, I'm able to acces the same port with cat /dev/ttyACM0 which seems to me sort of a problem about permissions.

The obvious turnaround is to use a second pi just for nod-red, but then, i couln't access openmtcprouter's system simply.

Does anyone has an idea on how to deal with such problem?

ho. yes, and for thoses who didn't catch it yet, i'm a linux newbie :slight_smile:

Thanks a lot for your help!