Mqtt to Modbus Incorrect Value

[vaughan.mcd]

I am having trouble with mqtt to modbus.

Off AirCon/SetOnOff=0
On AirCon/SetOnOff=1
Off modbus {"address":0,"state":true}
On modbus {"address":0,"state":true}

as you can see no matter if mqtt receives a message 0 or 1 when it passes to Modbus wright node
is shows as {"address":0,"state":true}

How do I send a {"address":0,"state":false} ?

[Steve-Mcl]

not enough info.

where / how do you attempt to change {"address":0,"state":true} to {"address":0,"state":false} based on the MQTT value? In a function? A change node? (copy and paste the function & a screenshot of your flow would be a start). include screenshots showing the data coming out of MQTT and out of your function/change node)

[E1cid]

An example

[{"id":"c88ee50b.60616","type":"inject","z":"57675e72.26a0d8","name":"1","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"1","payloadType":"num","x":300,"y":3920,"wires":[["6566afd8.d78ed8"]]},{"id":"6566afd8.d78ed8","type":"change","z":"57675e72.26a0d8","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"{\"address\":0,\"state\":$boolean(payload)}","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":490,"y":3880,"wires":[["7c3a6f44.9d4da"]]},{"id":"68bde274.646a64","type":"inject","z":"57675e72.26a0d8","name":"0","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"0","payloadType":"num","x":280,"y":3860,"wires":[["6566afd8.d78ed8"]]},{"id":"7c3a6f44.9d4da","type":"debug","z":"57675e72.26a0d8","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":720,"y":3880,"wires":[]}]

[vaughan.mcd]

Its doing something different

[{"id":"b9ee7504.de4d78","type":"tab","label":"Flow 1","disabled":false,"info":""},{"id":"d6bc5de9.9b116","type":"change","z":"b9ee7504.de4d78","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"{\"address\":0,\"state\":$boolean(payload)}","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":660,"y":260,"wires":[["e9110e0b.630f"]]},{"id":"e9110e0b.630f","type":"debug","z":"b9ee7504.de4d78","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":950,"y":260,"wires":[]},{"id":"74db1897.77ce18","type":"inject","z":"b9ee7504.de4d78","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"AirCon/SetOnOff","payload":"0","payloadType":"msg","x":320,"y":260,"wires":[["d6bc5de9.9b116"]]},{"id":"d4cda24.bd8556","type":"inject","z":"b9ee7504.de4d78","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"AirCon/SetOnOff","payload":"1","payloadType":"msg","x":330,"y":320,"wires":[["d6bc5de9.9b116"]]}]

When I tried it on my live flow it shows as below.

MQTT is sending
AirCon/SetOnOff=0
AirCon/SetOnOff=1

Modbus write node requires
fc=5 address=0 value=0
fc=5 address=0 value=1

[E1cid]

Make up your mind the first post said it require boolean true or false , then you say now 1 or 0
Edit jsonata expression and remove boolean,

{"fc":5,"address":0,"state":payload}

or without jsonata expression.

[{"id":"aeb45263.467678","type":"inject","z":"57675e72.26a0d8","name":"0","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"0","payloadType":"num","x":190,"y":3920,"wires":[["a080117c.795dd8"]]},{"id":"a080117c.795dd8","type":"change","z":"57675e72.26a0d8","name":"","rules":[{"t":"set","p":"hold","pt":"msg","to":"payload","tot":"msg"},{"t":"set","p":"payload","pt":"msg","to":"{\"fc\":5,\"address\":0}","tot":"json"},{"t":"move","p":"hold","pt":"msg","to":"payload.state","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":390,"y":3940,"wires":[["c7d62f3a.9ab3f"]]},{"id":"9dec0ca9.9bef68","type":"inject","z":"57675e72.26a0d8","name":"1","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"1","payloadType":"num","x":210,"y":3980,"wires":[["a080117c.795dd8"]]},{"id":"c7d62f3a.9ab3f","type":"debug","z":"57675e72.26a0d8","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":630,"y":3940,"wires":[]}]

If this fails please show us a debug of mqtt in nodes output.

[vaughan.mcd]

Sorry but this makes no sense to me, It will turn on but not off.
Even with the new rules it will not send state :false to Modbus. but its confusing because the Modbus device says it needs a value "0" to turn off. I believe the Modbus node handles address and function. Code.
Even though Modbus receives a value of 0 it should show as false in the Modbus response I think.

See the images of the two debug nodes and what the pick up.

[UnborN]

Hi .. in your flow your injects are not set to Number 0 and Number 1

try this

[{"id":"e9110e0b.630f","type":"debug","z":"94ab22aa.035ba","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":930,"y":620,"wires":[]},{"id":"74db1897.77ce18","type":"inject","z":"94ab22aa.035ba","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"AirCon/SetOnOff","payload":"true","payloadType":"bool","x":240,"y":540,"wires":[["cc5d800d.3d5528"]]},{"id":"d4cda24.bd8556","type":"inject","z":"94ab22aa.035ba","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"AirCon/SetOnOff","payload":"false","payloadType":"bool","x":250,"y":600,"wires":[["cc5d800d.3d5528"]]},{"id":"bd8ef1c9.41c448","type":"modbus-flex-write","z":"94ab22aa.035ba","name":"","showStatusActivities":false,"showErrors":false,"server":"bf37180a.2d18e","emptyMsgOnFail":false,"keepMsgProperties":false,"x":690,"y":640,"wires":[["e9110e0b.630f"],[]]},{"id":"cc5d800d.3d5528","type":"function","z":"94ab22aa.035ba","name":"","func":"msg.payload = { \n   \n    value: msg.payload, \n    'fc': 5, \n    'unitid': 1, \n    'address': 0 , \n    'quantity': 1 \n    \n} \n\nreturn msg\n","outputs":1,"noerr":0,"initialize":"","finalize":"","x":490,"y":640,"wires":[["bd8ef1c9.41c448"]]},{"id":"7e93a593.363944","type":"inject","z":"94ab22aa.035ba","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"AirCon/SetOnOff","payload":"1","payloadType":"num","x":230,"y":760,"wires":[["cc5d800d.3d5528"]]},{"id":"591ed24e.84118c","type":"inject","z":"94ab22aa.035ba","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"AirCon/SetOnOff","payload":"0","payloadType":"num","x":240,"y":820,"wires":[["cc5d800d.3d5528"]]},{"id":"e6cc9f4c.d8ea28","type":"comment","z":"94ab22aa.035ba","name":"or","info":"","x":230,"y":680,"wires":[]},{"id":"bf37180a.2d18e","type":"modbus-client","name":"","clienttype":"tcp","bufferCommands":true,"stateLogEnabled":false,"queueLogEnabled":false,"tcpHost":"192.168.1.66","tcpPort":"502","tcpType":"DEFAULT","serialPort":"/dev/ttyUSB","serialType":"RTU-BUFFERD","serialBaudrate":"9600","serialDatabits":"8","serialStopbits":"1","serialParity":"none","serialConnectionDelay":"100","unit_id":1,"commandDelay":20,"clientTimeout":1000,"reconnectOnTimeout":true,"reconnectTimeout":2000,"parallelUnitIdsAllowed":true}]

ps. modify the Modbus config to represent your settings.

[vaughan.mcd]

Thanks , Here are the results ?

[UnborN]

ok .. its seems that you are receiving strings from your MQTT
if you dont have control over the mqtt msg to make it to either Boolean True, False or Number 1, 0

then in Function node .. convert it to number yourself

msg.payload = { 
    value: Number(msg.payload), 
    'fc': 5, 
    'unitid': 1, 
    'address': 0 , 
    'quantity': 1     
} 

return msg

ps. by the way what is your Modbus unit ID ? dont forget to modify that as well if its not 'unitid': 1,

[vaughan.mcd]

Thank you that function node worked. Not sure why out of the whole thing the on and off gave me the most trouble.

[UnborN]

@vaughan.mcd

Not sure why out of the whole thing the on and off gave me the most trouble.

I believe its because you were using the Modbus Write node that only accepts a msg.payload with either Boolean or Number 0 or 1. Your attempts above were sending an object which wasnt a valid input for that node.

The Modbus Flex Write on the other hand allows you to send all the config (value, fc, unitid, address, quantity) as an object.

With either a Change node or a Function node you structure your payload in the correct format and it should work