How to use node-red to turn off an LED

[zhengtzer]

Hi


i know how to publish a switch status through mqtt and display on node-red dashboard

node-red.png (46.04 KiB) 1215 mal betrachtet

but now i am stuck on the other way around, how can i turn off an LED through subcribe?

subcribe.png (27.47 KiB) 1215 mal betrachtet

thanks
Jonathan

[rugee-f]

You can write a python prog where your incomming MQTT messages affect the TXT 4 IO (similar like you tried in RoboProCoding - I did this in plain python code...)

But the easier way to handle the IO of the TXT4 direct from Node-Red is to use the TXT4 API with HTTP requests.
With that you do not need a Python software layer to use the IO.

[zhengtzer]

Hi

"But the easier way to handle the IO of the TXT4 direct from Node-Red is to use the TXT4 API with HTTP requests.
With that you do not need a Python software layer to use the IO."

thanks for guiding me, and i tried to figure out whole day, now txt4.0 can receive the message, but the LED just cant be turn off
can you help me to look through and see which part had i do wrongly?tyty

my RPC

subcribePayload.png (213.67 KiB) 1096 mal betrachtet

my flow

node-red.png (125.2 KiB) 1096 mal betrachtet

my dashboard, know how to "control" the LED on dashboard only

nodeRedDashboard.png (42.19 KiB) 1096 mal betrachtet

thanks
Jonathan

[rugee-f]

I do not often use Blockly - with that I could not help you much.
I am using plain Python code - there I initialized my TXT4 IO as lamp (PWM) outputs and declared MQTT topics for the PWM setpoints.

declare_1.png (93.97 KiB) 1074 mal betrachtet

With incoming MQTT message on the setpoint topic I wrote the setpoint value to the TXT output.
0 for LED OFF and 255 for LED ON.

declare_2.png (84.14 KiB) 1074 mal betrachtet