Eck-Eck/src/main.cpp

// Copyright 2025 Elizabeth Cray
//
//    Licensed under the Apache License, Version 2.0 (the "License");
//    you may not use this file except in compliance with the License.
//    You may obtain a copy of the License at
//
//        http://www.apache.org/licenses/LICENSE-2.0
//
//    Unless required by applicable law or agreed to in writing, software
//    distributed under the License is distributed on an "AS IS" BASIS,
//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//    See the License for the specific language governing permissions and
//    limitations under the License.

#include <Arduino.h>
#include <EEPROM.h>
#include <ctype.h>
#include "cw.h"

/* TODO:
 * - Implement sending strings
 * - Add OLED Support
 */

boolean debug = true;
uint8_t input_dit = 3, input_dah = 6, input_pot = A6;
uint8_t output = 7;
uint16_t dit = 200, dah = 500;
uint8_t debounce = 50;
uint16_t p_tol = 30, p_min = 50, p_max = 2000, p_buf = 0, p_cache = 0;
String serial_buffer = "";
char buf;

void key_string(String);
void adjust_length(uint16_t);
void set_length(uint16_t, uint16_t);
void send(bool);
void process_input(String);
void log(String);

void setup() {
  Serial.begin(115200);
  log("Set PinModes\n");
  pinMode(input_dit, INPUT_PULLUP);
  pinMode(input_dah, INPUT_PULLUP);
  pinMode(input_pot, INPUT);
  pinMode(output, OUTPUT);
  digitalWrite(output, LOW);
  log("Read EEPROM\n");
  dit = EEPROM.read(20);
  dah = EEPROM.read(21);
  debug = EEPROM.read(22);
  p_buf = analogRead(input_pot);
  // adjust_length(p_buf);
  log("Setup complete\n");
  log("Dit length: ");
  log(String(dit));
  log("\n");
  log("Dah length: ");
  log(String(dah));
  log("\n");
  log("Potentiometer: ");
  log(String(p_buf));
  log("\n");
}

void loop() {
  if (!digitalRead(input_dah)){
    send(true);
  }else if (!digitalRead(input_dit)){
    send(false);
  }

  p_cache = analogRead(input_pot);
  if (abs(p_cache - p_buf) > p_tol){
    p_buf = p_cache;
    if (p_cache < p_min){
      p_cache = p_min;
    } else if (p_cache > p_max){
      p_cache = p_max;
    }
    adjust_length(p_cache);
  }

  if (Serial.available() > 0) {
    buf = Serial.read();
    if ((uint16_t) buf == 13){
      process_input(serial_buffer);
      serial_buffer = "";
    } else if ((uint8_t) buf > 27 ){
      serial_buffer += buf;
    }
  }

  delay(debounce);
}

void adjust_length(uint16_t adjusted_length){
  uint16_t new_dah = map(adjusted_length, 20, 1000, p_min, p_max);
  set_length(new_dah/2, new_dah);
}

void process_input(String input){
  // Commands:
  // S<string>    send string as CW, unavail chars become " "
  // I<int>       set did length (ms)
  // A<Int>       set dah length (ms)
  // D<0/1>       set debug mode
  log("Processing input: ");
  log(input);
  log("\n");
  char command = input[0];
  input.remove(0,1);
  log("Command: ");
  log(String(command));
  log(" - ");
  log(input);
  log("\n");
  uint16_t length = 0;

  if (islower(command)){
    command = toupper(command);
  }
  switch(command){
  case 'S':
    key_string(input);
    break;
  case 'I':
    length = input.toInt();
    set_length(length, dah);
    break;
  case 'A':
    length = input.toInt();
    set_length(dit, length);
    break;
  case 'D':
    debug = boolean(input.toInt()==1);
    log("Debug mode enabled");
    EEPROM.write(22, debug);
    break;
  default:
    Serial.println('?');
    break;
  }
}

void key_string(String input){
  // log("Sending string: ");
  // log(input);
  // log("\n");
  uint8_t b = 0; 
  for (uint8_t i = 0; i < input.length(); i++){
    char c = input[i];
    if ((uint8_t)c != 32){
      b = convertASCII(c);
      for(uint8_t y = 0; y < strlen(morseCode[b]); y++){
        send(morseCode[b][y] == '.');
        delay(dit);
      }
      if(debug){
        Serial.print(' ');
      }
      delay(dit);
    } else {
      if (debug){
        Serial.println("");
      }
      delay(dah);
    }
  }
}

void send(bool b) {
  if (debug){
    Serial.print(b?"+":"=");
  }
  digitalWrite(output, HIGH);
  delay(b?dit:dah);
  digitalWrite(output, LOW);
}

void set_length(uint16_t length_dit, uint16_t length_dah) {
  log("Setting dit length to ");
  log(String(length_dit));
  log(" and dah length to ");
  log(String(length_dah));
  log("\n");
  dit = length_dit;
  dah = length_dah;
  EEPROM.write(20, length_dit);
  EEPROM.write(21, length_dah);
  return;
}

void log(String content){
  if (debug){
    Serial.print(content);
  }
}