Sat, 10 Dec 2011 14:56:27 +0100
some pitlane fixing
ISR ( TIMER1_COMPA_vect ) { PORTC ^= _BV(PC0); // DEBUG OUTPUT SYSTEM CLOCK // trigger packet transfer: if (sysclk_packettimer == 14) { // 15*500 = 7500 NS transmit_len = transmit_len_next; sysclk_packettimer = 0; } else sysclk_packettimer++; // here is some more time to do something else... // reset both car counters to overflow car0_old = TIMER1_500NS; car1_old = TIMER1_500NS; sysclk.value++; // increment 500ns timer } ISR ( TIMER2_COMP_vect ) { uint8_t i; //OCR2 = TIMER2_50US; // make sure that timer2 is 50µs !!! // data packet timer 100µs pro bit... if (transmit_len >= 0xFE) { if (transmit_len != 0xFF) { RAIL_POWER_PORT |= _BV(RAIL_POWER); // end of transmission transmit_len = 0xFF; transmit_buffer = transmit_buffer_queue; transmit_buffer_queue = 0; transmit_len_next = transmit_len_queue; // start the response receiver timer // TODO: only on 8 timeslots, not on every transmission // TODO: give slot number to timer - then store the transmission to 8 slots array TCNT0 = TIMER0_250US; timer0_delay = TIMER0_2300NS; response = 0; response_len = 0; TIMSK |= _BV(TOIE0); // Try to read the stuff on the response wire TIMSK &= ~_BV(OCIE2); // temporarily disable timer2 interrupts responsewire_data = 0; // wait a little and look if wire goes low i = 100; while ( ((PIN(RESPONSEWIRE_PORT) & _BV(RESPONSEWIRE_PIN)) != 0) && (i>0) ) { i--; _delay_us(5); } if (i>0) { // response incoming! // start feew µs later _delay_us(5); for (i=16; i>0; i--) { // start receiving all 16 bits PORTC ^= _BV(PC1); // DEBUG responsewire_data = (responsewire_data << 1); // shift bits if ((PIN(RESPONSEWIRE_PORT) & _BV(RESPONSEWIRE_PIN)) == 0) // phsyical low == logic 1 responsewire_data |= 1; _delay_us(48); // get to next bit } itoa(responsewire_data, s, 16); RS232_puts("RW:"); RS232_puts(s); RS232_putc('\n'); } TIMSK |= _BV(OCIE2); //enable timer2 interrupt // end reading response wire } } else { uint16_t bit = (1<<(transmit_len & 0b01111111)); uint16_t clock; if ((transmit_len & 0b10000000) == 0) clock = 0; else clock = 0xffff; if ( ((transmit_buffer ^ clock) & bit) != 0 ) RAIL_POWER_PORT |= _BV(RAIL_POWER); else RAIL_POWER_PORT &= ~_BV(RAIL_POWER); if ( (transmit_len & 0b10000000) == 0 ) { // block 0 //if (transmit_len == 0) transmit_len = 0xFF; else transmit_len |= 0b10000000; // set clock transmit_len |= 0b10000000; // set clock } else { // block 1, output the current bit transmit_len &= 0b01111111; // reset clock //if (transmit_len != 0) transmit_len--; // next bit if (transmit_len == 0) transmit_len = 0xFE; else transmit_len--; // next bit } } } ISR ( TIMER0_OVF_vect ) { // TODO: last bit should be set by the sender, not from us! TCNT0 = TIMER0_250US; if (timer0_delay == 0) { RAIL_POWER_PORT &= ~_BV(RAIL_POWER); // pull rails low _delay_us(28); // wait some cycles if ((PIN(RAIL_DETECT_PORT) & _BV(RAIL_DETECT)) != 0) { // check for logic zero if (response == 0) { // there is no start bit, so stop the timer and cancel response receiving TIMSK &= ~_BV(TOIE0); } else { // we received a bit (logic low) response = response << 1; response_len++; } } else { // okay, we have logic high response = response << 1; response |= 1; response_len++; } if (response_len == 15) { // maximum response length reached RAIL_POWER_PORT |= _BV(RAIL_POWER); // restore rails power TIMSK &= ~_BV(TOIE0); } else { _delay_us(20); // wait some cycles RAIL_POWER_PORT |= _BV(RAIL_POWER); // restore rails power } } else timer0_delay--; // 2.3 ms delay not reached yet } ISR (INT0_vect) { // car0 detector uint16_t tmp = 0; car0_new = TCNT1; // get current counter if (car0_old < car0_new) { // calculate difference if (car0 == 0) tmp = car0_new-car0_old; if ( (tmp > 54) && (tmp < 74) ) car0 = 1; if ( (tmp > 118) && (tmp < 138) ) car0 = 2; if ( (tmp > 186) && (tmp < 206) ) car0 = 3; if ( (tmp > 246) && (tmp < 266) ) car0 = 4; if ( (tmp > 310) && (tmp < 330) ) car0 = 5; if ( (tmp > 374) && (tmp < 394) ) car0 = 6; } car0_old = car0_new; } ISR (INT1_vect) { // car1 detector uint16_t tmp = 0; car1_new = TCNT1; // get current counter if (car1_old < car1_new) { // calculate difference if (car1 == 0) tmp = car1_new-car1_old; if ( (tmp > 54) && (tmp < 74) ) car1 = 1; if ( (tmp > 118) && (tmp < 138) ) car1 = 2; if ( (tmp > 186) && (tmp < 206) ) car1 = 3; if ( (tmp > 246) && (tmp < 266) ) car1 = 4; if ( (tmp > 310) && (tmp < 330) ) car1 = 5; if ( (tmp > 374) && (tmp < 394) ) car1 = 6; } car1_old = car1_new; } ISR (INT2_vect) { // Lap counter Interrupt // do not know if this ever occurs ?! this is normally an output pin to trigger the counter start }