PID5752_QuadEncoder_demo.ino

/*
 * This is a demo for a QT Py RP2040 connected to a quad rotary encoder breakout
 * using the onboard Stemma QT Port
 * https://www.adafruit.com/product/4900
 * https://www.adafruit.com/product/5752
 * 
 */
#include "Adafruit_seesaw.h"
#include <seesaw_neopixel.h>

#define SS_NEO_PIN       18
#define SS_ENC0_SWITCH   12
#define SS_ENC1_SWITCH   14
#define SS_ENC2_SWITCH   17
#define SS_ENC3_SWITCH   9

#define SEESAW_ADDR      0x49

Adafruit_seesaw ss = Adafruit_seesaw(&Wire);
seesaw_NeoPixel pixels = seesaw_NeoPixel(4, SS_NEO_PIN, NEO_GRB + NEO_KHZ800);

int32_t enc_positions[4] = {0, 0, 0, 0};

void setup() {
  Serial.begin(115200);
  while (!Serial) delay(10);

  Serial.println("Looking for seesaw!");
  
  if (! ss.begin(SEESAW_ADDR) || !pixels.begin(SEESAW_ADDR)) {
    Serial.println("Couldn't find seesaw on default address");
    while(1) delay(10);
  }
  Serial.println("seesaw started");
  uint32_t version = ((ss.getVersion() >> 16) & 0xFFFF);
  if (version  != 5752){
    Serial.print("Wrong firmware loaded? ");
    Serial.println(version);
    while(1) delay(10);
  }
  Serial.println("Found Product 5752");

  ss.pinMode(SS_ENC0_SWITCH, INPUT_PULLUP);
  ss.pinMode(SS_ENC1_SWITCH, INPUT_PULLUP);
  ss.pinMode(SS_ENC2_SWITCH, INPUT_PULLUP);
  ss.pinMode(SS_ENC3_SWITCH, INPUT_PULLUP);
  ss.setGPIOInterrupts(1UL << SS_ENC0_SWITCH | 1UL << SS_ENC1_SWITCH | 
                       1UL << SS_ENC2_SWITCH | 1UL << SS_ENC3_SWITCH, 1);

  
  // get starting positions
  for (int e=0; e<4; e++) {
    enc_positions[e] = ss.getEncoderPosition(e);
    ss.enableEncoderInterrupt(e);
  }
  
  Serial.println("Turning on interrupts");

  pixels.setBrightness(255);
  pixels.show(); // Initialize all pixels to 'off'
}

void loop() {

  if (! ss.digitalRead(SS_ENC0_SWITCH)) {
    Serial.println("ENC0 pressed!");
  }
  if (! ss.digitalRead(SS_ENC1_SWITCH)) {
    Serial.println("ENC1 pressed!");
  }
  if (! ss.digitalRead(SS_ENC2_SWITCH)) {
    Serial.println("ENC2 pressed!");
  }
  if (! ss.digitalRead(SS_ENC3_SWITCH)) {
    Serial.println("ENC3 pressed!");
  }


  for (int e=0; e<4; e++) {
    int32_t new_enc_position = ss.getEncoderPosition(e);
    // did we move around?
    if (enc_positions[e] != new_enc_position) {
      Serial.print("Encoder #");
      Serial.print(e);
      Serial.print(" -> ");
      Serial.println(new_enc_position);      // display new position
      enc_positions[e] = new_enc_position;      // and save for next round
      
      // change the neopixel color, mulitply the new positiion by 4 to speed it up
      pixels.setPixelColor(e, Wheel((new_enc_position*4) & 0xFF));
      pixels.show();
    }
  }

  // don't overwhelm serial port
  delay(10);
}


uint32_t Wheel(byte WheelPos) {
  WheelPos = 255 - WheelPos;
  if (WheelPos < 85) {
    return seesaw_NeoPixel::Color(255 - WheelPos * 3, 0, WheelPos * 3);
  }
  if (WheelPos < 170) {
    WheelPos -= 85;
    return seesaw_NeoPixel::Color(0, WheelPos * 3, 255 - WheelPos * 3);
  }
  WheelPos -= 170;
  return seesaw_NeoPixel::Color(WheelPos * 3, 255 - WheelPos * 3, 0);
}