#define CHANNELS 4 #define SAMPLE_CACHE_LENGTH 16 // Must be power of 2 (8, 16, etc.); See cache.h for implementation #define HIT_THRES 750 // The thresholds are also dependent on SAMPLE_CACHE_LENGTH, if you #define RESET_THRES 100 // changed SAMPLE_CACHE_LENGTH, you must also adjust thresholds #define SAMPLING_PERIOD 500 // Sampling period in microseconds, 500us = 0.5ms = 2000Hz #define DEBUG 0 #include "cache.h" #include "keyboard.h" Cache inputWindow[CHANNELS]; unsigned long power[CHANNELS]; unsigned long lastPower[CHANNELS]; bool triggered; unsigned long triggeredTime[CHANNELS]; const byte inPins[] = {36, 39, 34, 35}; // L don, L kat, R don, R kat const byte outPins[] = {25, 26, 27, 14}; // LED visualization (optional) const char outKeys[] = {'f', 'd', 'j', 'k'}; // L don, L kat, R don, R kat float sensitivity[] = {1.0, 1.0, 1.0, 1.0}; short maxIndex; float maxPower; unsigned long lastTime; void setup() { Serial.begin(250000); for (byte i = 0; i < CHANNELS; i++) { power[i] = 0; lastPower[i] = 0; triggered = false; pinMode(inPins[i], INPUT); pinMode(outPins[i], OUTPUT); } maxIndex = -1; maxPower = 0; xTaskCreate(bluetoothTask, "bluetooth", 20000, NULL, 5, NULL); lastTime = micros(); } void loop() { if (maxIndex != -1 && lastPower[maxIndex] < RESET_THRES) { triggered = false; digitalWrite(outPins[maxIndex], LOW); maxIndex = -1; maxPower = 0; } for (byte i = 0; i < CHANNELS; i++) { inputWindow[i].put(analogRead(inPins[i])); power[i] = sensitivity[i] * (power[i] - inputWindow[i].get(1) + inputWindow[i].get()); if (lastPower[i] > maxPower && power[i] < lastPower[i]) { maxPower = lastPower[i]; maxIndex = i; } lastPower[i] = power[i]; #if DEBUG Serial.print(power[i]); Serial.print(" "); #endif } if (!triggered && maxPower >= HIT_THRES) { triggered = true; digitalWrite(outPins[maxIndex], HIGH); #if !DEBUG if (isBleConnected) { typeChar(outKeys[maxIndex]); } #endif } #if DEBUG Serial.print("\n"); #endif unsigned int frameTime = micros() - lastTime; if (frameTime < SAMPLING_PERIOD) { delayMicroseconds(SAMPLING_PERIOD - frameTime); } lastTime = micros(); }