digitalRead on TX pin always "LOW"

GasperStef · September 12, 2022, 6:29pm

Hello to all,

I am trying to program a simple keyboard which is using shortcuts and macros.
For the controller, I am using Keyestuido Pro micro. Because I am short with pins, I am trying to use also TX pin as digitalRead.

But when I upload the program, it seems as if this pin is always LOW and is triggering the key.

I know, that I cannot use Serial.print command with this and I don't.

#include <Keyboard.h>

// set pin numbers for the five buttons:
const int Yminus = 0;
const int Xminus = 2;

...

void setup() { // initialize the buttons' inputs:
  pinMode(Yminus, INPUT);
  pinMode(Xminus, INPUT);

...

  Keyboard.begin();
}
void loop() {
  // use the pushbuttons to control the keyboard:
  if (digitalRead(Yminus) == LOW) {
    Keyboard.press(arrowDown);
    Keyboard.releaseAll();
    delay(3000);
  }

This program is automatically triggering pin D00 every 3 seconds.

I have checked if the button is not working and this is not the case.
Also I have checked if maybe when I soldered the Pro micro made a shortcut, and this is also not the case.

Can you help me please with this issue?

Thank you in advance.

pmagowan · September 12, 2022, 6:39pm

Welcome, read the guide to the forum at the top of every section and tidy up your code in code tags <|>. Edit with

LarryD · September 12, 2022, 6:41pm

Assume you know the Analog pins can be used as digital pins.

er_name_not_found · September 13, 2022, 6:41am

Is the board still connected to your computer's USB port?

killzone_kid · September 13, 2022, 7:58am

This is RX pin looks like TX pin is 1

red_car · September 13, 2022, 8:15am

Agree with @killzone_kid

Show all your code. How many pins are you using?

GasperStef · September 14, 2022, 3:58pm

Yes. This is very clear for me.

GasperStef · September 14, 2022, 4:03pm

Ok. This is my mistake. Yes it is on RX pin. I also tried addressing pin 1 and 0. Same result.

GasperStef · September 14, 2022, 4:07pm

My code is:

#include <Keyboard.h>


// set pin numbers for the buttons:
const int Yminus = 0;
const int Xminus = 2;
const int Rapid = 3;
const int Xplus = 4;
const int Zminus = 5;
const int Yplus = 6;
const int Zplus = 7;
const int ZeroX = 8;
const int ZeroZ = 9;
const int ZeroY = 10;
const int RST = 16;
const int SpindleStart = 14;
const int RefPoint = 15;
const int GoTo0 = 18;
const int CycleStop = 19;
const int Hold = 20;
const int CycleStart = 21;
char ctrlKey = KEY_LEFT_CTRL;
char altKey = KEY_LEFT_ALT;
char arrowUp = KEY_UP_ARROW;
char arrowDown = KEY_DOWN_ARROW;
char arrowR = KEY_RIGHT_ARROW;
char arrowL = KEY_LEFT_ARROW;
char zPlus = KEY_PAGE_UP;
char zMinus = KEY_PAGE_DOWN;
char goHome = KEY_HOME;
char goToZero = KEY_DELETE;
char setZeroX = KEY_LEFT_ARROW;
char setZeroY = KEY_LEFT_ARROW;
char setZeroZ = KEY_LEFT_ARROW;
char alarmUnlock = KEY_END;
char cycleStop = KEY_ESC;
char startHold = KEY_TAB;
char stepDown = '-';
int stepCount = 1;
int programStateU = 0;
int buttonStateU;
long buttonMillisU = 0;
int programStateD = 0;
int buttonStateD;
long buttonMillisD = 0;
const long intervalButton = 500;

void setup() { // initialize the buttons' inputs:
  pinMode(Yminus, INPUT);
  pinMode(Xminus, INPUT);
  pinMode(Rapid, INPUT);
  pinMode(Xplus, INPUT);
  pinMode(Zminus, INPUT);
  pinMode(Yplus, INPUT);
  pinMode(Zplus, INPUT);
  pinMode(ZeroX, INPUT);
  pinMode(ZeroZ, INPUT);
  pinMode(ZeroY, INPUT);
  pinMode(RST, INPUT);
  pinMode(SpindleStart, INPUT);
  pinMode(RefPoint, INPUT);
  pinMode(GoTo0, INPUT);
  pinMode(CycleStop, INPUT);
  pinMode(Hold, INPUT);
  pinMode(CycleStart, INPUT);


  Keyboard.begin();
}
void loop() {
  // use the pushbuttons to control the keyboard:
  if (digitalRead(Yminus) == LOW) {
    Keyboard.press(arrowDown);
    Keyboard.releaseAll();
    delay(3000);
  }
  if (digitalRead(Xminus) == LOW) {
    Keyboard.press(arrowL);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(Rapid) == LOW && stepCount < 4) {
    Keyboard.press(ctrlKey);
    Keyboard.press('u');
    Keyboard.releaseAll();
    stepCount++;
    delay(250);
  }
  if (digitalRead(Rapid) == LOW && stepCount == 4) {
    Keyboard.press(ctrlKey);
    Keyboard.press('j');
    Keyboard.releaseAll();
    Keyboard.press(ctrlKey);
    Keyboard.press('j');
    Keyboard.releaseAll();
    Keyboard.press(ctrlKey);
    Keyboard.press('j');
    Keyboard.releaseAll();
    stepCount = 1;
    delay(250);
  }
  if (digitalRead(Xplus) == LOW) {
    Keyboard.press(arrowR);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(Zminus) == LOW) {
    Keyboard.press(zMinus);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(Yplus) == LOW) {
    Keyboard.press(arrowUp);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(Zplus) == LOW) {
    Keyboard.press(zPlus);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(ZeroX) == LOW) {
    Keyboard.write('x');
    delay(250);
  }
  if (digitalRead(ZeroZ) == LOW) {
    Keyboard.write('z');
    delay(250);
  }
  if (digitalRead(ZeroY) == LOW) {
    Keyboard.write('y');
    delay(250);
  }
  if (digitalRead(RST) == LOW) {
    Keyboard.press(alarmUnlock);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(RefPoint) == LOW) {
    Keyboard.press(goHome);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(GoTo0) == LOW) {
    Keyboard.press(goToZero);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(CycleStop) == LOW) {
    Keyboard.press(cycleStop);
    Keyboard.releaseAll();
    delay(250);
  }
  if (digitalRead(Hold) == LOW) {
    Keyboard.press(startHold);
    Keyboard.releaseAll();
    delay(250);
  }
  unsigned long currentMillisU = millis();
  buttonStateU = digitalRead(CycleStart);
  if (buttonStateU == LOW && programStateU == 0) {
    buttonMillisU = currentMillisU;
    programStateU = 1;
    Keyboard.press('q');
    Keyboard.releaseAll();
    delay(250);
  }
  else if (programStateU == 1 && buttonStateU == HIGH) {
    programStateU = 0;
  }
  if (currentMillisU - buttonMillisU > intervalButton && programStateU == 1) {
    programStateU = 0;
    Keyboard.press(ctrlKey);
    Keyboard.press('r');
    Keyboard.releaseAll();
    delay(500);
  }
  unsigned long currentMillisD = millis();
  buttonStateD = digitalRead(SpindleStart);
  if (buttonStateD == LOW && programStateD == 0) {
    buttonMillisD = currentMillisD;
    programStateD = 1;
    Keyboard.press('a');
    Keyboard.releaseAll();
    delay(250);
  }
  else if (programStateD == 1 && buttonStateD == HIGH) {
    programStateD = 0;
  }
  if (currentMillisD - buttonMillisD > intervalButton && programStateD == 1) {
    programStateD = 0;
    Keyboard.press(ctrlKey);
    Keyboard.press('r');
    Keyboard.releaseAll();
    delay(500);
  }

}

Additionaly I am adding also picture of PCB.

killzone_kid · September 14, 2022, 4:27pm

Why are you showing PCB? Is the problem occurring while everything mounted on PCB?

GasperStef · September 14, 2022, 4:58pm

Honestly, I do not know. I programed it on PCB. But after checking with multimeter everything seams OK. The button, capa, diode and resistor.

system · March 13, 2023, 4:59pm

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digitalRead on TX pin always "LOW"

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