Address 2x LCD 2004 via html

General
1

Hello,
I would like to address 2 LCD 2004 via html or the like with a payload. Reason: Currently, communication is running via the I2C interface. The I2C bus is massively disturbed by my built-in solenoid valves (irrigation system).
Now I would like to address the LCD (2x) from Nodered via html protocol. At the moment I am using the "http reguest node" with the following command:
http://192.168.178.134/control?cmd=lcd,1,1,"{{msg.payload}}} "
For example, an elapsing time is displayed in the payload.
Is there another possibility (node) to transfer the payload to the display?
In addition, I can only address one display with this display. A second display is not addressed.
I installed an ESP 8266 with EspEasy on the display.
So I would like to transfer the data to the displays via WLAN, in the hope that the interference from my solenoid valves will not come into play.
In this case, MQTT can only transfer numbers, not text.
This is probably due to ESPEasy.
Does anyone have a good idea or a solution?

Many Thanks

pine_pinie

2

Have you searched the palette for LCD?

I have tested two different nodes, both successfully, with my 20x4 LCD.

The whole topic is here - Trying to send text to LCD over i2c contrib

But the contribs I used are here...

3

Looks like I missed this part within all the leadup.

So, now the LCD(s) is/are on another MCU and you need to send data from Node-Red to that device (setup as an MQTT client and with LCD library). What makes you think MQTT can't send text?

And with MQTT, you should be able to send to either display based on subscription topics.

4

Hello,

as already written. With I2C I can control two displays. That's how it is currently structured. The I2C bus is massively disturbed during switching operations. Then I only see wild symbols on the display.

The display is installed on an ESP 8266 with the ESPEASY software. Allegedly the MQTT interface of ESPEASY cannot process any text. Currently it only works with numbers.
Of course, MQTT can transfer everything, but unfortunately not yet in ESPEASY.
With the node "http request" I can control one display via html, but unfortunately not the second one.

5

Then don't use ESPEASY... I have looked it over and remain unimpressed. It is not hard to figure out a little Arduino code, what with the gazzillion examples and tutorials out there.

I would recommend using something like pubsubclient along with an appropriate i2c LCD library and then you can have the ease of MQTT and both displays.

6

Hello,

You are right.
But my knowledge is very little. That's why I ended up at ESPEASY.
I understood you theoretically. So I'm supposed to put together a project under Arduiono IDE?
I will definitely fail there.
But the tip is still very good.

Thanks very much!

7

To send text to an LED, a quick google search (espeasy how to send msg to lcd) came up with this:
https://www.letscontrolit.com/forum/viewtopic.php?t=3449

ESPEasy can send text, you just need to do it in RULES with a 'publish'. If ou look at the documentation you will find:

Send command using MQTT broker service

Publish,<topic>,<value>

The <value> can be a string.

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8

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