Multiple cases with multiple actions

General
1

Hello everybody, I don't have programming experience and I need your help.

I am using node-red to analyze a tcp-output string that includes this sequence: "00000000" (8 characters).
This is sent by an electronic card that has 8 inputs (each "0" corresponds to an input).
If an input is activated, the corresponding "0" changes to "1" and for each input activation I need to send an e-mail with a specific text.
E.g. 10000000 (first input active), 10100000 (1st and 3rd are active) etc.

I can create a switch node with each case, but that would be quite difficult, because more than 1 input can be activated at the same time. Or perhaps another input is activated while others are already active.

I think a function node should be created, but I don't know exactly how. Can you help please?
Thank you.

2

Do you mean that each time the string arrives that you have to send one message dependent on the pattern, or one message for each 1 in the string?
Can the text for the message be worked out automatically? Perhaps tell us what the text would consist of.

3

image
image875Ă—389 29.6 KB

Demo flow...

[{"id":"f23bfd68.03fe1","type":"inject","z":"5e6c8b.7f38b374","name":"Simulate TCP data 00000000","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"00000000","payloadType":"str","x":920,"y":80,"wires":[["7448498f.5c0428"]]},{"id":"c25fb754.4bf128","type":"debug","z":"5e6c8b.7f38b374","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":1190,"y":140,"wires":[]},{"id":"7448498f.5c0428","type":"function","z":"5e6c8b.7f38b374","name":"","func":"var bitString = msg.payload; // or wherever your data is.\nif ( bitString === \"00000000\" ) {\n    msg.payload = \"All off.\";\n    return msg;\n}\nif ( bitString === \"11111111\" ) {\n    msg.payload = \"All on.\";\n    return msg;\n}\n\nvar strTemp = [];\nfor (let bitIdx = 0; bitIdx < 8; bitIdx++) {\n    if(bitString[bitIdx] == \"1\") {\n        strTemp.push([\"1st\",\"2nd\",\"3rd\",\"4th\",\"5th\",\"6th\",\"7th\",\"8th\"][bitIdx])\n    }\n}\n\nif(strTemp.length > 0) {\n    var s1 = strTemp.join(\", \");\n    var s2 = strTemp.length > 1 ? \" are on.\" : \" is on.\"\n    msg.payload = s1.trim() + s2;\n    return msg;\n} \n","outputs":1,"noerr":0,"initialize":"","finalize":"","x":1180,"y":80,"wires":[["c25fb754.4bf128"]]},{"id":"b3038865.23be78","type":"inject","z":"5e6c8b.7f38b374","name":"Simulate TCP data 10000000","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"10000000","payloadType":"str","x":920,"y":120,"wires":[["7448498f.5c0428"]]},{"id":"72e0dea7.e06df","type":"inject","z":"5e6c8b.7f38b374","name":"Simulate TCP data 10000001","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"10000001","payloadType":"str","x":920,"y":160,"wires":[["7448498f.5c0428"]]},{"id":"b1dd8d2a.62b9a","type":"inject","z":"5e6c8b.7f38b374","name":"Simulate TCP data 10100101","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"10100101","payloadType":"str","x":920,"y":200,"wires":[["7448498f.5c0428"]]},{"id":"8ea22f58.1d8a9","type":"inject","z":"5e6c8b.7f38b374","name":"Simulate TCP data 11111111","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"11111111","payloadType":"str","x":920,"y":240,"wires":[["7448498f.5c0428"]]}]
4

Thank you for your replies.
Each input will have a different text, for example input1 text might be "faulty zone1", while input2 be "rain sensor was activated.
I don't need a specific message for any multiple inputs, but to send one message each time one input is activated.

5

Thats not what you asked for.

Again, not what you asked for.

to save us wasting time, please be PRECISE

6

With my examples I was just trying to explain the structure of my string.
But you are right, I should have been more precise. I'm sorry.

7

Change the function to this...

const bitString = msg.payload; // or wherever your data is.
const onPayload = "ON" ;//change to whatever you desire
const offPayload = "OFF" ;//change to whatever you desire

//Define bit descriptions - EDIT THESE
const bitDefinitions = [
    "faulty zone1","rain sensor",
    "input 3","input 4",
    "input 5","input 6",
    "input 7","input 8"]; 

//get last values from memory
var memory = context.get("memory") || ["0","0","0","0","0","0","0","0"];

//split the string into an array
var values = bitString.split("");

//compare bitString to memory & send a message if different
for (let bitIdx = 0; bitIdx < 8; bitIdx++) {
    if(bitString[bitIdx] !== memory[bitIdx]) {
        node.send({
            topic: bitDefinitions[bitIdx],
            payload: bitString[bitIdx] == "1" ? onPayload: offPayload
        })
    }
}

//store actual values for next time
context.set("memory", values);

You should get...

DpHjxDu5z7
DpHjxDu5z7705Ă—653 73.4 KB

if you are not interested in the "OFF" signals, use a SWITCH node after and check the payload is == "ON"

if you want true and false edit the constants in the function,

This should be enough to get you moving.

1 Like
8

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