Problem interfacing Nextion display with Raspberry Pi 4

Software Development
1

Hi,
I am trying to interface a Nextion 2.4" Display with Raspberry Pi 4. The Nextion display is connected to the RPi 4 as shown in the diagram below:

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The test program that I want to run should display the I.P. address on the display. Using the pyserial library, I have written the following code:
‘’’
Program to establish UART communication with Nextion display
‘’’
import serial
from binascii import unhexlify

ser = serial.Serial ("/dev/ttyS0", 9600)    #Open port with baud rate

my_string='FF'

ser.write("t0.txt=")
ser.write("\"")
ser.write("192.168.178.34")
ser.write("\"")
ser.write(unhexlify(my_string))
ser.write(unhexlify(my_string))
ser.write(unhexlify(my_string))

I have also sniffed the TX pin from the RPi 4 and the data is exactly as expected. The following terminal window shows the captured data:

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Unfortunately, the I.P. address is not getting displayed on the Nextion Screen. I have also debugged the Display and it displays the data as expected:

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Could anyone point to me where I messed up? Thanks!

Regards
Frederic

2

Do you see anything at all coming to or from the display? If you just spit out received values and power cycle the screen, do you get data back to the pi?