diff options
Diffstat (limited to 'src/main.cpp')
| -rw-r--r-- | src/main.cpp | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/src/main.cpp b/src/main.cpp new file mode 100644 index 0000000..8a058c9 --- /dev/null +++ b/src/main.cpp @@ -0,0 +1,239 @@ +#include <Arduino.h> +#include <Wire.h> +const uint8_t SlaveDeviceId = 0x02; + +uint16_t receivedPacket[10]; + +byte bytesSent = 0; +byte buffer[2]; + +uint16_t returninfo; + +int watchDog = 0; +bool fallback = false; +unsigned long tick = 0; +int pins[18] = {0, 0, 0, 1, 0, 2, 3, 0, 0, 4, 5, 6, 0, 0, 0, 0, 0, 0}; // map to array +int pin_map[7] = {0, 3, 5, 6, 9, 10, 11}; +int target[7] = {0, 0, 0, 0, 0, 0, 0}; +int current[7] = {0, 0, 0, 0, 0, 0, 0}; +int i; + +/** + * Divides a given PWM pin frequency by a divisor. + * + * The resulting frequency is equal to the base frequency divided by + * the given divisor: + * - Base frequencies: + * o The base frequency for pins 3, 9, 10, and 11 is 31250 Hz. + * o The base frequency for pins 5 and 6 is 62500 Hz. + * - Divisors: + * o The divisors available on pins 5, 6, 9 and 10 are: 1, 8, 64, + * 256, and 1024. + * o The divisors available on pins 3 and 11 are: 1, 8, 32, 64, + * 128, 256, and 1024. + * + * PWM frequencies are tied together in pairs of pins. If one in a + * pair is changed, the other is also changed to match: + * - Pins 5 and 6 are paired on timer0 + * - Pins 9 and 10 are paired on timer1 + * - Pins 3 and 11 are paired on timer2 + * + * Note that this function will have side effects on anything else + * that uses timers: + * - Changes on pins 3, 5, 6, or 11 may cause the delay() and + * millis() functions to stop working. Other timing-related + * functions may also be affected. + * - Changes on pins 9 or 10 will cause the Servo library to function + * incorrectly. + * + * Thanks to macegr of the Arduino forums for his documentation of the + * PWM frequency divisors. His post can be viewed at: + * https://forum.arduino.cc/index.php?topic=16612#msg121031 + */ +void setPwmFrequency(int pin, int divisor) { + byte mode; + if(pin == 5 || pin == 6 || pin == 9 || pin == 10) { + switch(divisor) { + case 1: mode = 0x01; break; + case 8: mode = 0x02; break; + case 64: mode = 0x03; break; + case 256: mode = 0x04; break; + case 1024: mode = 0x05; break; + default: return; + } + if(pin == 5 || pin == 6) { + TCCR0B = ((TCCR0B & 0b11111000) | mode); + } else { + TCCR1B = ((TCCR1B & 0b11111000) | mode); + } + } else if(pin == 3 || pin == 11) { + switch(divisor) { + case 1: mode = 0x01; break; + case 8: mode = 0x02; break; + case 32: mode = 0x03; break; + case 64: mode = 0x04; break; + case 128: mode = 0x05; break; + case 256: mode = 0x06; break; + case 1024: mode = 0x07; break; + default: return; + } + TCCR2B = ((TCCR2B & 0b11111000) | mode); + } +} + +void receiveDataPacket(int howMany){ + if(fallback == true || watchDog == 0) + { + fallback = false; + digitalWrite(LED_BUILTIN, LOW); + } + watchDog = 10; + + // get bytes from i2c + bytesSent = 0; // clear byte counter + for(byte i=0; i < howMany; i++){ + receivedPacket[i] = Wire.read(); + } + +} + +void slavesRespond(){ + if(bytesSent == 0){ + switch(receivedPacket[0]){ + case 1: // digitalWrite + /* + receivedPacket[1] = pin + receivedPacket[2] = value + */ + pinMode(receivedPacket[1], OUTPUT); // set pin mode + digitalWrite(receivedPacket[1], receivedPacket[2]); + returninfo = 1; + break; + case 2: // digitalRead + /* + receivedPacket[1] = pin + */ + pinMode(receivedPacket[1], INPUT); // set pin mode + returninfo = digitalRead(receivedPacket[1]); + break; + case 3: // digitalRead pullup + /* + receivedPacket[1] = pin + */ + pinMode(receivedPacket[1], INPUT_PULLUP); // set pin mode + returninfo = digitalRead(receivedPacket[1]); + break; + case 4: // analogWrite + /* + receivedPacket[1] = pin + receivedPacket[2] = value + */ + pinMode(receivedPacket[1], OUTPUT); // set pin mode + analogWrite(receivedPacket[1], receivedPacket[2]); + returninfo = 1; + break; + case 5: // analogRead + /* + receivedPacket[1] = pin + */ + returninfo = analogRead(receivedPacket[1]); + break; + case 10: // analogWriteSlow + /* + receivedPacket[1] = pin + receivedPacket[2] = value + */ + if(pins[receivedPacket[1]] > 0) { + pinMode(pins[receivedPacket[1]], OUTPUT); // set pin mode + target[pins[receivedPacket[1]]] = receivedPacket[2]; + returninfo = 1; + } else { + returninfo = 0; + } + break; + } + } + if(bytesSent == 0){ //send first byte + buffer[0] = returninfo >> 8; + buffer[1] = returninfo & 0xff; + Wire.write(buffer[0]); + bytesSent++; + } else if(bytesSent == 1){ // send second byte + Wire.write(buffer[1]); + bytesSent = 0; // clear byte counter + } +} + +void setup() { + setPwmFrequency(3, 8); + setPwmFrequency(5, 8); + setPwmFrequency(6, 8); + setPwmFrequency(9, 8); + setPwmFrequency(10, 8); + setPwmFrequency(11, 8); + + pinMode(3, OUTPUT); + pinMode(5, OUTPUT); + pinMode(6, OUTPUT); + pinMode(9, OUTPUT); + pinMode(10, OUTPUT); + pinMode(11, OUTPUT); + + analogWrite(3, 0); + analogWrite(5, 0); + analogWrite(6, 0); + analogWrite(9, 0); + analogWrite(10, 0); + analogWrite(11, 0); + + Wire.begin(SlaveDeviceId); // join i2c bus with Slave ID + Wire.onReceive(receiveDataPacket); // register talk event + Wire.onRequest(slavesRespond); // register callback event + + pinMode(LED_BUILTIN, OUTPUT); + digitalWrite(LED_BUILTIN, HIGH); +} + +void adjust_pwm(int &l, int p, int m) { + if (l < m) { + if (l >= m - 5) { + l = m; + } else { + l += 5; + } + analogWrite(p, l); + } + + if (l > m) { + if (l <= 5) { + l = 0; + } else { + l -= 5; + } + analogWrite(p, l); + } +} + +void loop() { + for(i=1; i<8; i++) { + if(target[i]!=current[i] || fallback && 255!=current[i]) { + adjust_pwm(current[i],pin_map[i],fallback ? 255 : target[i]); + } + } + + if(millis() - tick >= 5000) { + tick = millis(); + if(watchDog > 0) + { + watchDog--; + } + else + { + fallback = true; + digitalWrite(LED_BUILTIN, HIGH); + } + } + + delay(10); +} + |