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Issues with setting serial communication

Hi,

I started to play with the nextion nx4024t032 display. I created very simple page with one text element and one text button.

Later I wanted to send different text to the text element t0 via serial line (t0.txt="changed_txt"). I have an FTDI USB to Serial converter. I connected it to nextion and started minicom (I use Linux) with serial line parameter 9600 8n1. Unfortunately I am not able to send anything to the nextion.

When I power on nextion I receive:


��������


I also enabled "Send component ID" for the button in the nextion editor. When I check the serial monitor during clicking on the button I can see:


e���e���e���e���


When hitting any key on the keyboard, no letters are being displayed in the serial monitor, but I can see led blinks on the FTDI. The same converter works perfectly with arduino, so I do not consider there is a hw problem.


To be honest, I have no clue how to succeed with the serial communication to/from nextion. Any help would be appreciated.


Could it be a 3.3 vs 5 volt issue? Do you know what your ftdi supports? In your nextion editor you can set the baud rate to ensure it is 9600. It should be but you never know.
I have ftdi which has a jumper for selecting 5v or 3.3v. I have set it up as 5V and I also powered the nextion from the ftdi's 5v and gnd.
But I did another test using arduino - connected the nextion to arduino's tx/rx and now I am able to successfully update txt element using this function:


 

void writeTxt( int element, int txt ) {
  Serial.print("t");
  Serial.print(element);
  Serial.print(".txt=\"");
  Serial.print(txt);
  Serial.print("\"");
  Serial.write(0xff);
  Serial.write(0xff);
  Serial.write(0xff);
}

 

 

So calling 

 

writeTxt(0, 200);

 

will update t0 text element's txt to 200. It just works.

But I still do not know why it does not work with ftdi usb to serial board via picocom or minicom.

The real FTDI chips don't seem to work for me, but the knock-off chinese USB to serial do work.  Try one of these 


http://www.ebay.com/itm/6Pin-USB-2-0-to-TTL-UART-Module-Serial-Converter-CP2102-STC-Replace-Ft232-NEW-/261822072637?hash=item3cf5cfc73d


Hi,
I got it workusing the same ftdi usb to serial adapter, but this time not with minicom or picocom, but like this:


 

echo -ne "t0.txt=\"`date +%H:%M:%S`\"\xFF\xFF\xFF" > /dev/ttyUSB0

 

This command updated t0.txt element in nextion with current time. But I have no clue why I can't type anything in minicom or picocom.

 

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