xpt2046 touchscreen and teensy 4.0

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Keith_M

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Disregard this post Issue Resolved ...Sometimes you miss things at 2:30 AM ..!!!

I recently purchased some 2.8" TFTs from PJRC // ili9341 .. no problems generating graphics works great and very fast over SPI

However I am unable to get the XPT2046 touchscreen feature running which is driving me crazy ..

I've can compile the example scripts and upload them and execute them. However, Serial monitor is just printing between 0,0 and 8192 and does not respond to any pressure applied to the screen.

Can somebody school me on the wiring configuration ? .. All lines for TFT display are hooked up and running no issues there .. but the touch hardware configuration has me stumped.. I've got Touch_IRQ to pin2 of the teensy 4.0 and Touch_CS to pin 8 of the teensy..

some guidance would be great... !!!

Sourcefile: any of the XPT2046 samples .
Error Messages:None
Hardware:Teensy 4.0 .. ILI9341 2.8" TFT Display

Wiring ILI9341. Teensy 4.0
Vcc. 3.3V
Reset. Tied High (3.3v)
LED. Tied high ( 3.3V) through 100 Ohm resistor
DC. Pin 9
CS Pin 10
MOSI. Pin 11
MISO. Pin 12
SCLK. Pin 13
T_CS. Pin 8
T_IRQ. Pin 2

Software .. Imac High Sierra 10.13.6
Arduino 1.8.12
Teensyduino 1.52
Libraries. XPT2046 ver.1.3.0
ILI9341_T3 ...
 
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Well ..my hardware environment ..I suspect ...it seems I could either have a tft display or touch ..but not both ..still have the problem ...I was developing on your typical plastic plugin protoboard ...so what was happening is I'd run the TFT graphics test sketch ..fine no issues ...then if I pulled off the wires off the display and ran the touch and monitored via the serial monitor... touch would work fine ...however when I paralled up S_CLK and T_CLK to get both working The TFT would not display graphics !! ...I suspect my protoboard has too much stray capacitance when I parallel the 2 clocks up and the display dropped out .....(well thats what Im running on in theory)..I wired accordingly to the pinout for the t4 for both TFT and touch..So got caught off guard....what was important at the time was to establish functionality of both the TFT and the touchscreen ..as they had not been used ....anyhow if I'm off base with this ,or I'm wiring incorrectly..some direction would be welcome. Thanks for the reply..
 
Got off the plastic protoboard ...sketches for both TFT and touch are running fine ..no issues ...
 
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