// // apa.io.c // // APA I/O node // // set lfuse to 0x7E for 20 MHz xtal // // Neil Gershenfeld // CBA MIT 7/3/11 // // (c) Massachusetts Institute of Technology 2011 // Permission granted for experimental and personal use; // license for commercial sale available from MIT. // #include #include #define PWM_pin (1 << PA5) #define PWM_port PORTA #define PWM_direction DDRA //#define BLINK PINA = _BV(5) volatile int16_t position = 0; volatile bool position_changed = false; static volatile uint8_t state = 0; unsigned char path_to_host[apa_max_packet]; unsigned char path_to_host_length = 0; bool path_to_host_stored = false; void blink3(){ unsigned char i = 0; for (i; i <3; i++){ PORTA |= _BV(PA5); // turn LED ON _delay_ms(100); // wait 1 sec PORTA &= ~(_BV(PA5)); // turn LED OFF _delay_ms(100); } } // // process the packet // void apa_process_packet(struct apa_port_type *port) { uint16_t pwm; //,ad; unsigned char pwml, pwmh, i; //, adl, adh; // // execute command // switch (port->payload_out[0]) { case 'u': // u: PWM up pwm = OCR1B; pwm += -1; OCR1B = pwm; pwmh = pwm >> 8; pwml = pwm & 255; port->payload_out[0] = pwmh; port->payload_out[1] = pwml; port->payload_out_length = 2; break; case 'd': // d: PWM down pwm = OCR1B; pwm += 1; OCR1B = pwm; pwmh = pwm >> 8; pwml = pwm & 255; port->payload_out[0] = pwmh; port->payload_out[1] = pwml; port->payload_out_length = 2; break; case 'n': // n: PWM on OCR1B = 0; pwmh = 0; pwml = 0; port->payload_out[0] = pwmh; port->payload_out[1] = pwml; port->payload_out_length = 2; break; case 'f': // f: PWM off OCR1B = 1023; pwmh = 3; pwml = 255; port->payload_out[0] = pwmh; port->payload_out[1] = pwml; port->payload_out_length = 2; break; case 'r': // r: PWM read pwm = OCR1B; pwmh = pwm >> 8; pwml = pwm & 255; port->payload_out[0] = pwmh; port->payload_out[1] = pwml; port->payload_out_length = 2; break; case 'w': // w: PWM write pwm = apa_hex_int(&port->payload_out[1]); OCR1B = pwm; pwmh = pwm >> 8; pwml = pwm & 255; port->payload_out[0] = pwmh; port->payload_out[1] = pwml; port->payload_out_length = 2; break; case 'p': // save path to host for future usage for (i = 0; i < port->path_out_length; ++i) path_to_host[i] = port->path_out[i]; //path_to_host[i] = '0'; path_to_host_length = port->path_out_length; port->payload_out[0] = port->id; port->payload_out_length = 1; path_to_host_stored = true; blink3(); break; case ' ': // do nothing port->path_out_length = 0; port->payload_out_length = 0; default: // unknown command port->payload_out[0] = '?'; port->payload_out_length = 1; break; } } // // Configure interrupt pins // void configInt(void){ GIMSK = _BV(PCIE0); // turns on pin change interrupts PCMSK0 = _BV(PCINT2) | _BV(PCINT3); // turn on interrupts on pins PCINT2 PCINT3 sei(); // enables interrupts } // // ISR - interrupt service routine // ISR (PCINT0_vect){ updateEncoder(); } // // increment/decrement position variable // void updateEncoder(void){ // _______ _______ // Pin1 ______| |_______| |______ Pin1 // negative <--- _______ _______ __ --> positive // Pin2 __| |_______| |_______| Pin2 // new new old old // pin2 pin1 pin2 pin1 Result // ---- ---- ---- ---- ------ // 0 0 0 0 no movement // 0 0 0 1 +1 // 0 0 1 0 -1 // 0 0 1 1 +2 (assume pin1 edges only) // 0 1 0 0 -1 // 0 1 0 1 no movement // 0 1 1 0 -2 (assume pin1 edges only) // 0 1 1 1 +1 // 1 0 0 0 +1 // 1 0 0 1 -2 (assume pin1 edges only) // 1 0 1 0 no movement // 1 0 1 1 -1 // 1 1 0 0 +2 (assume pin1 edges only) // 1 1 0 1 -1 // 1 1 1 0 +1 // 1 1 1 1 no movement uint8_t s = state & 3; uint8_t reading = PINA; if (reading & _BV(PA2)) s |= 4; // put '1' into the 3rd bit - 01** if (reading & _BV(PA3)) s |= 8; // put '1' into the 4th bit - 10** switch (s) { case 0: case 5: case 10: case 15: break; case 1: case 7: case 8: case 14: position = 1; position_changed = true; break; case 2: case 4: case 11: case 13: position = 2; position_changed = true; break; case 3: case 12: position = 3; position_changed = true; break; default: position = 4; position_changed = true; break; } state = (s >> 2); // shift two bits left to keep the old ones XXXX => **XX } // // send out encoder position // void apa_encoder_check(struct apa_port_type *port) { unsigned char i; if (position_changed && path_to_host_stored){ position_changed = false; for (i = 0; i < path_to_host_length; ++i) port->path_out[i] = path_to_host[i]; port->path_out_length = path_to_host_length; port->payload_out[0] = position; port->payload_out_length = 1; //BLINK; } else { //PORTA &= ~(_BV(PA5)); // turn LED OFF } } // // main // int main(void) { static struct apa_port_type port_0, port_1; //, port_2; // // set clock divider to /1 // CLKPR = (1 << CLKPCE); CLKPR = (0 << CLKPS3) | (0 << CLKPS2) | (0 << CLKPS1) | (0 << CLKPS0); // // using blue led to debug encoder readouts // DDRA |= _BV(PA5); // set pin PA5 as an output PORTA |= _BV(PA5); // turn LED ON _delay_ms(1000); // wait 1 sec PORTA &= ~(_BV(PA5)); // turn LED OFF // // set up PWM pins // // TCCR1A = ((1 << COM1B1) | (1 << COM1B0) | (1 << WGM11) // | (1 << WGM10)); // clear OC1B on compare match, fast 8-bit PWM // TCCR1B = ((0 << WGM13) | (1 << WGM12) | (0 << CS12) | (0 << CS11) // | (1 << CS10)); // /1 clock divider // OCR1B = 1023; // clear(PWM_port, PWM_pin); // output(PWM_direction, PWM_pin); // // initialize ports and pins // port_0.pins_in = &PINA; port_0.port_out = &PORTB; port_0.direction_out = &DDRB; port_0.pin_in = (1 << PA7); port_0.pin_out = (1 << PB2); port_0.path_in_length = 0; port_0.path_out_length = 0; port_0.id = '0'; port_0.next_port = &port_1; clear(*port_0.port_out, port_0.pin_out); output(*port_0.direction_out, port_0.pin_out); // port_1.pins_in = &PINA; port_1.port_out = &PORTA; port_1.direction_out = &DDRA; port_1.pin_in = (1 << PA0); port_1.pin_out = (1 << PA1); port_1.path_in_length = 0; port_1.path_out_length = 0; port_1.id = '1'; port_1.next_port = &port_0; /// !!!!!!!!!!!!!!!!!!!!!!!!! clear(*port_1.port_out, port_1.pin_out); output(*port_1.direction_out, port_1.pin_out); // // port_2.pins_in = &PINA; // port_2.port_out = &PORTA; // port_2.direction_out = &DDRA; // port_2.pin_in = (1 << PA4); // port_2.pin_out = (1 << PA6); // port_2.path_in_length = 0; // port_2.path_out_length = 0; // port_2.id = '2'; // port_2.next_port = &port_0; // clear(*port_2.port_out, port_2.pin_out); // output(*port_2.direction_out, port_2.pin_out); // // power on delay // power_on_delay(); blink3(); // // configure interrupt pins // configInt(); // // main loop // while (1) { apa_port_scan(&port_0); apa_port_scan(&port_1); //apa_port_scan(&port_2); apa_encoder_check(&port_0); // // check for sync start // // if (0 != pin_test(*port_1.pins_in, port_1.pin_in)) { // apa_get_packet(&port_1); // if (port_1.path_in_length != 0) { // apa_move_packet(&port_1,&port_0); // apa_put_packet(&port_0); // } // } } }