Button press output errors - assistance needed

[Dave71]

Hi. Ive got a Teensy 4.0 setup to send midi notes via usb to a piece of software but I'm getting errors in the notes being sent. I have 12 momentary buttons wired up using the keypad library and have tested the setup using a simple serial.print command for each button. I've found some issues with button 7 output. Button 7 is setup to print Btn7 and send midi note 6 with velocity of 127 on channel 1 but i get inconsistent data being sent.

As far as far as i can tell, the issue is related just to button 7. Suspected a wiring issue but that should create a constant fault? I'll work on a schematic to show the wiring as soon a possible for clarification

Here's the code for button 7 - complete code is below

Thanks...Dave

if (customKey == '7') {
usbMIDI.sendNoteOn(6, 127, 1);
delay(50);
usbMIDI.sendNoteOff(6, 127, 1);
Serial.println("Btn7");
}

Serial monitor is picking this up from numerous presses of button 7 - all the other buttons appear to be ok
Btn7
Btn1
Btn1
Btn7
Btn7
Btn1
Btn7
Btn1
Btn1


#include <Keypad.h>
#include <MIDI.h>


const byte ROWS =2;
const byte COLS =6;

char hexaKeys[ROWS][COLS] = {
{'1', '2', '3', '4', '5', '6'},
{'7', '8', '9', 'A', 'B', 'C'},
};

byte rowPins[ROWS] = {1, 2,};
byte colPins[COLS] = {3, 4 ,5, 6, 7, 8};

Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

void setup(){
Serial.begin(9600);
pinMode(14, OUTPUT);
}


void loop()

{
digitalWrite(14, HIGH);


{
char customKey = customKeypad.getKey();

if (customKey == '1') {
usbMIDI.sendNoteOn(0, 127, 1);
delay(50);
usbMIDI.sendNoteOff(0, 127, 1);
Serial.println("Btn1");
}

if (customKey == '2') {
usbMIDI.sendNoteOn(1, 127, 1);
delay(50);
usbMIDI.sendNoteOff(1, 127, 1);
Serial.println("Btn2");
}

if (customKey == '3') {
usbMIDI.sendNoteOn(2, 127, 1);
delay(50);
usbMIDI.sendNoteOff(2, 127, 1);
Serial.println("Btn3");
}

if (customKey == '4') {
usbMIDI.sendNoteOn(3, 127, 1);
delay(50);
usbMIDI.sendNoteOff(3, 127, 1);
Serial.println("Btn4");
}

if (customKey == '5') {
usbMIDI.sendNoteOn(4, 127, 1);
delay(50);
usbMIDI.sendNoteOff(4, 127, 1);
Serial.println("Btn5");


}

if (customKey == '6') {
usbMIDI.sendNoteOn(5, 127, 1);
delay(50);
usbMIDI.sendNoteOff(5, 127, 1);
Serial.println("Btn6");
}

if (customKey == '7') {
usbMIDI.sendNoteOn(6, 127, 1);
delay(50);
usbMIDI.sendNoteOff(6, 127, 1);
Serial.println("Btn7");
}

if (customKey == '8') {
usbMIDI.sendNoteOn(7, 127, 1);
delay(50);
usbMIDI.sendNoteOff(7, 127, 1);
Serial.println("Btn8");
}

if (customKey == '9') {
usbMIDI.sendNoteOn(8, 127, 1);
delay(50);
usbMIDI.sendNoteOff(8, 127, 1);
Serial.println("Btn9");
}

if (customKey == 'A') {
usbMIDI.sendNoteOn(9, 127, 1);
delay(50);
usbMIDI.sendNoteOff(9, 127, 1);
Serial.println("Btn10");
}

if (customKey == 'B') {
usbMIDI.sendNoteOn(10, 127, 1);
delay(50);
usbMIDI.sendNoteOff(10, 127, 1);
Serial.println("Btn11");
}

if (customKey == 'C') {
usbMIDI.sendNoteOn(11, 127, 1);
delay(50);
usbMIDI.sendNoteOff(11, 127, 1);
Serial.println("Btn 12");
}
}
}

 

[mjs513]

Sounds like you need to add the debounce function to setup. From the keypad library.

// Minimum debounceTime is 1 mS. Any lower *will* slow down the loop().
void Keypad::setDebounceTime(uint debounce) {
    debounce<1 ? debounceTime=1 : debounceTime=debounce;
}

 

[Dave71]

Thanks for the reply. Was my understanding a debouce was already built into the library but will add that anyway.
main issue is why I’m getting random button 1 press when I hit button 7

 

[PaulStoffregen]

Try setting Tools > CPU Speed for slower, like 150 MHz or even 24 MHz. Quick and easy way to test if running too quickly for signals to stabilize.

 

[Dave71]

Great, thanks for that. Seems to have cured the issue. 50+ button pushes later and I’ve got 100% success rate

thanks again!