reTerminal DM: Cannot read digital input

Products & Technology
#1

Hello,
I have a problem reading the digital IO from Node-RED.

I have read the Node-RED starting guide and getting started with reTerminal DM – unfortunately, I could not find an answer.

In documentation it is specified that Digital Input 1 is GPIO pin 16. Therefor I have connected a position sensor into Digital Input 1 and ground to GND_INPUT.

Unfortunately when I change the position I don’t read anything in the Node-RED. With my voltmeter I can confirm that the position sensor is outputing 24V when triggered and 0 when not.

Is there something I need to do?

Best regards,
Jakub Szlaur

Node-RED program:

[
    {
        "id": "a9c27808bef7b34a",
        "type": "debug",
        "z": "103c0611d42ccc43",
        "name": "debug 24",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "payload",
        "targetType": "msg",
        "statusVal": "",
        "statusType": "auto",
        "x": 560,
        "y": 200,
        "wires": []
    },
    {
        "id": "b13d3ca712220c36",
        "type": "pi-gpiod in",
        "z": "103c0611d42ccc43",
        "name": "",
        "host": "localhost",
        "port": 8888,
        "pin": "16",
        "intype": "PUD_OFF",
        "debounce": "25",
        "read": true,
        "x": 310,
        "y": 200,
        "wires": [
            [
                "a9c27808bef7b34a"
            ]
        ]
    },
    {
        "id": "0c4a26fd670926f0",
        "type": "pi-gpiod in",
        "z": "103c0611d42ccc43",
        "name": "",
        "host": "localhost",
        "port": 8888,
        "pin": "17",
        "intype": "PUD_OFF",
        "debounce": "25",
        "read": true,
        "x": 310,
        "y": 240,
        "wires": [
            [
                "a9c27808bef7b34a"
            ]
        ]
    }
]
#2

I have noticed that the input GPIO node is actually changing according to the position sensor.

  • But it only changes after redeployment of the whole Node-RED! See video attachment.
  • I have connected DI1 to output signal of the Festo position sensor and DI_GND to ground of the Festo position sensor
  • I know for sure that there is voltage because my voltmeter reads 24V when triggered and 0V when not triggered.

How can I solve this problem?

This is the link for the video: video_demonstration.mp4 - VEED