// // hello.ftdi.44.echo.c // // 115200 baud FTDI character echo, with flash string // // set lfuse to 0x7E for 20 MHz xtal // // Neil Gershenfeld // 12/8/10 // // (c) Massachusetts Institute of Technology 2010 // Permission granted for experimental and personal use; // license for commercial sale available from MIT. // #include #include #include #include #define output(directions,pin) (directions |= pin) // set port direction for output #define input(directions,pin) (directions &= (~pin)) // set port direction for input #define set(port,pin) (port |= pin) // set port pin #define clear(port,pin) (port &= (~pin)) // clear port pin #define pin_test(pins,pin) (pins & pin) // test for port pin #define bit_test(byte,bit) (byte & (1 << bit)) // test for bit set #define bit_delay_time 102 // bit delay for 115200 with overhead //102 for 9600, 8.5 for 115200 #define bit_delay() _delay_us(bit_delay_time) // RS232 bit delay #define half_bit_delay() _delay_us(bit_delay_time/2) // RS232 half bit delay #define char_delay() _delay_ms(10) // char delay #define led_delay() _delay_ms(100) #define on_delay() _delay_us(3) #define fast_off_delay() _delay_us(1) #define medium_off_delay() _delay_us(3) #define slow_off_delay() _delay_us(5) #define PWM_count 200 #define cycle_count 5 #define bridge_port PORTA #define bridge_direction DDRA #define IN1 (1 << PA3) #define IN2 (1 << PA2) #define led_port PORTB #define led_direction DDRB #define led_pin (1 << PB1) #define switch_port PORTB #define switch_pin (1 << PB2) #define switch_direction DDRB #define switch_pins PINB #define max_buffer 25 void get_char(volatile unsigned char *pins, unsigned char pin, char *rxbyte) { // // read character into rxbyte on pins pin // assumes line driver (inverts bits) // *rxbyte = 0; while (pin_test(*pins,pin)) // // wait for start bit // ; // // delay to middle of first data bit // half_bit_delay(); bit_delay(); // // unrolled loop to read data bits // if pin_test(*pins,pin) *rxbyte |= (1 << 0); else *rxbyte |= (0 << 0); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 1); else *rxbyte |= (0 << 1); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 2); else *rxbyte |= (0 << 2); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 3); else *rxbyte |= (0 << 3); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 4); else *rxbyte |= (0 << 4); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 5); else *rxbyte |= (0 << 5); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 6); else *rxbyte |= (0 << 6); bit_delay(); if pin_test(*pins,pin) *rxbyte |= (1 << 7); else *rxbyte |= (0 << 7); // // wait for stop bit // bit_delay(); half_bit_delay(); } void put_char(volatile unsigned char *port, unsigned char pin, char txchar) { // // send character in txchar on port pin // assumes line driver (inverts bits) // // start bit // clear(*port,pin); bit_delay(); // // unrolled loop to write data bits // if bit_test(txchar,0) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,1) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,2) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,3) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,4) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,5) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,6) set(*port,pin); else clear(*port,pin); bit_delay(); if bit_test(txchar,7) set(*port,pin); else clear(*port,pin); bit_delay(); // // stop bit // set(*port,pin); bit_delay(); // // char delay // bit_delay(); } void put_string(volatile unsigned char *port, unsigned char pin, char *str) { // // print a null-terminated string // static int index; index = 0; do { put_char(port, pin, str[index]); ++index; } while (str[index] != 0); } void flash() { clear(led_port, led_pin); led_delay(); set(led_port, led_pin); } int main(void) { // // main // static char chr; static char buffer[max_buffer] = {0}; static int index; static uint16_t count; static uint8_t cycle; // // set clock divider to /1 // CLKPR = (1 << CLKPCE); CLKPR = (0 << CLKPS3) | (0 << CLKPS2) | (0 << CLKPS1) | (0 << CLKPS0); // // initialize output pins // //set(serial_port, serial_pin_out); //input(serial_direction, serial_pin_out); ///output(serial_direction, serial_pin_out); set(led_port, led_pin); output(led_direction, led_pin); set(switch_port, switch_pin); input(switch_direction, switch_pin); clear(bridge_port, IN1); output(bridge_direction, IN1); clear(bridge_port, IN2); output(bridge_direction, IN2); // // main loop // index = 0; while(1){ if (0 == pin_test(switch_pins, switch_pin)){ for (count = 0; count < PWM_count; ++count) { set(bridge_port, IN1); _delay_us(100); //on_delay(); clear(bridge_port, IN1); _delay_us(3); //slow_off_delay(); } } //_delay_us(1000000); //clear(bridge_port, IN2); //set(bridge_port, IN1); /* for (count = 0; count < PWM_count; ++count) { set(bridge_port, IN1); _delay_us(30); //on_delay(); clear(bridge_port, IN1); _delay_us(1); //slow_off_delay(); } */ /* for (cycle = 0; cycle < cycle_count; ++cycle){ clear(bridge_port, IN1); set(bridge_port, IN2); for (count = 0; count < PWM_count; ++count) { set(bridge_port, IN2); on_delay(); clear(bridge_port, IN2); slow_off_delay(); } clear(bridge_port, IN2); set(bridge_port, IN1); for (count = 0; count < PWM_count; ++count) { set(bridge_port, IN1); on_delay(); clear(bridge_port, IN1); slow_off_delay(); } } */ //_delay_us(100); //} /*while (1) { get_char(&serial_pins, serial_pin_in, &chr); put_string(&serial_port, serial_pin_out, "hello.ftdi.44.echo.c: you typed \""); buffer[index++] = chr; if (index == (max_buffer-1)) index = 0; put_string(&serial_port, serial_pin_out, buffer); put_char(&serial_port, serial_pin_out, '\"'); put_char(&serial_port, serial_pin_out, 10); // new line }*/ } }