New to JSON commands - please help

Software
1

Hi
I have a NexGen wifi communications module, and I want to publish on/off commands to it.
I have got as far as subscribing to it and getting {“data”:[85]} responses. Does anyone know what that means?

I can see in the user guide that I should send commands like this:
The NexGen module supports very basic MQTT usage. It can be configured to connect to an MQTT broker using no auth or basic auth(username/password). Testing of this functionality was done using beebotte.com

The module only implements one subscribe topic and one publish topic. It listens for control commands over the subscribe topic and sends command responses to the publish topic. Commands should be published to the subscribe topic in a JSON packet. The JSON packet must contain one key value pair with a key of sendCommand and the value for that pair must be a JSON array of command bytes. Example: {“sendCommand”:[254,108,1]}. The WiFi module will publish data received from the host board to the Publish topic. This Publish payload will contain a JSON packet. The format of the packet is a single key value pair with the key of data and the value will be an array of bytes. Example: {“data”:[170,1,85,1]}

Is there anywhere where I can find out what the bytes mean? I am just looking for two commands: one to switch on and one to switch off.

Also, does anyone know how I can do that in c#?

Many thanks

Jo Ling

2

Hi Jo,

All commands for operating ProXR relays can be found in this document:

To turn relay 1 on the publish message would be:
{“sendCommand”:[254,108,1]}
To turn relay 1 off the publish message would be:
{“sendCommand”:[254,100,1]}

The {“data”:[85]} response you are getting back lets you know the controller received and executed the command. The relay should click. If it does not then ensure you are powering the relay controller with a 12VDC power supply.

Thank you,
Travis Elliott

3

Thank you. Very useful!

Best Regards

Jo Ling

1 Like