I have a couple of questions:
1) Does the pre-installed demo send out serial commands?
2) I am using a USB TTL serial cable to my computer. I am using a terminal program. Should I see data coming back when I am touching the screen objects?
I currently have the terminal program set to 9600,N,8,1
Should I be using other settings?
1) The pre-installed demo sends serial messages when you are on page 6 and you press on the picture (touch area m0 or m1). See pictures :
Message from m0 on 2.4" Nextion: 0x65 0x06 0x09 0x00 0xFF 0xFF 0xFF (and 0x04 0xFF 0xFF 0xFF from the third press).
2) Yes, you should see the data on any terminal program. See picture :
I use the same settings 9600,N,8,1.
You can also use the Nextion Debug window to see the serial messages from the display.
Click on 'Debug' icon in the Nextion Editor window, then choose 'Serial Port', choose your COM port number and click on 'Connect'.
Then you can press the display and you will see the serial messages at the bottom of the window.
You can also write commands (without 0xFF 0xFF 0xFF) and see the result on the display.
See picture :