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Visitor II
March 31, 2020
Solved

How to Programatically update variables via the Write Panel Node.

  • March 31, 2020
  • 3 replies
  • 1336 views

Hi I am trying to use the Write Panel Mode in my flow to inject values into my target device (via the STM link).

I have setup the Write Panel Node (following the nodes instructions) and the Node works as expected, whereby I can enter values into the variable spaces on the dashboard and when I hit the 'write' key it send it to my target and updates the values.

What I wanted to know, is there a way to programatically trigger the 'Write' from the node red flow instead of using the dashboard button??

0693W000000V590QAC.jpg

This is my example flow.

0693W000000V59eQAC.jpg

The 'inject vals' node is a basic node red 'inject' node. I was hoping to use this node to write values into the 'Write panel' node and get it tp send the values to the target without havind to press the 'write' button on the bashboard.

Any help is appreciated

Cheers

Michael

    This topic has been closed for replies.
    Best answer by Landry

    Dear Michael,

    To write data by flow, the following payload must be sent to probe out node ,with the topic “write�? :

    {

       "variablelist": [

           {

               "address": "0x20000060",

               "type": 4,

               "value": "xxxx"

           }

       ],

       "accesspoint": 0

    }

    You can find detailed explanations in this thread :

    https://community.st.com/s/question/0D53W000000ayg1SAA/hello-how-is-it-possible-to-change-a-variable-by-pressing-a-buttoni-just-can-change-a-variable-by-using-the-write-panel-butregards

    If you need more support , please come back to me .

    Landry

    3 replies

    LandryAnswer
    Visitor II
    March 31, 2020

    Dear Michael,

    To write data by flow, the following payload must be sent to probe out node ,with the topic “write�? :

    {

       "variablelist": [

           {

               "address": "0x20000060",

               "type": 4,

               "value": "xxxx"

           }

       ],

       "accesspoint": 0

    }

    You can find detailed explanations in this thread :

    https://community.st.com/s/question/0D53W000000ayg1SAA/hello-how-is-it-possible-to-change-a-variable-by-pressing-a-buttoni-just-can-change-a-variable-by-using-the-write-panel-butregards

    If you need more support , please come back to me .

    Landry

    Visitor II
    March 31, 2020

    Hi Landry

    Yes thats just the ticket :thumbs_up:

    Thanks for your support buddy

    Just a couple of questions:

    Will there be new nodes added to the interface soon?

    Can I control the ethernet port on my target board through node red (I take it I would read/write into to the relevant registers associated with the ethernet port?)

    Cheers

    Michael

    ST Employee
    April 2, 2020

    Hello Michael

    New nodes could be added in future releases, but you can already add existing community nodes to make your own flows.

    It is possible to write directly in the hardware registers of the STM32. i.e., you can easily control a led by writing in the GPIOx BSRR register.

    The control of Ethernet port by accessing the registers through SWD may be possible, but seems to be complex. I don't know what is your goal, but it may be easier for your application to use the embedded software to control the Ethernet.

    Best regards

    Stephane