T-Display-S3 Noisy Output and Unreliable timing
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Not sure why but there appears to be a lot of noise on the output pin when toggling its output there is also times when the output timing does not comply with the code.
I am using GPIO3 in this routine but the jitter appears on all of the outputs.
Referring to the screen shot you can see the edges are not clean and one of the pulses is approximatley 22us when it should be 15us as per my code below..?
One of the things I have noticed is that the RED led is flashing rapidly when connected to the USB port but it does not flash when powered by external PSU. The noise appears to be related and my feeling is that there is some sort of routine still running from flash in the background but I am unable to view the memory...?Arduino Code
#include <TFT_eSPI.h>TFT_eSPI tft;
void setup() {
pinMode(3,OUTPUT);
//tft.begin();
//tft.setRotation(1);
//tft.fillScreen(TFT_BLUE);
}void loop() {
digitalWrite(3, HIGH); // Set pin 16 high
delayMicroseconds(15); // Delay 15 microseconds
digitalWrite(3, LOW); // Set pin 16 low
delayMicroseconds(15); // Delay 15 microseconds
}Screen shot from Oscillscope
