diff options
Diffstat (limited to 'protocol')
| -rw-r--r-- | protocol/serial_soft.c (renamed from protocol/serial.c) | 47 |
1 files changed, 43 insertions, 4 deletions
diff --git a/protocol/serial.c b/protocol/serial_soft.c index b5c2ae317..b7d06b644 100644 --- a/protocol/serial.c +++ b/protocol/serial_soft.c @@ -38,12 +38,19 @@ POSSIBILITY OF SUCH DAMAGE. #include <stdbool.h> #include <avr/io.h> #include <avr/interrupt.h> +#include <util/delay.h> #include "serial.h" +/* + * Stupid Inefficient Busy-wait Software Serial + * is still useful for negative logic signal like Sun protocol not supported by hardware USART. + */ + +#define WAIT_US (1000000/SERIAL_BAUD) void serial_init(void) { - SERIAL_RX_INIT(); + SERIAL_RXD_INIT(); } // RX ring buffer @@ -64,12 +71,44 @@ uint8_t serial_recv(void) return data; } -// USART RX complete interrupt -ISR(SERIAL_RX_VECT) +//ISR(INT2_vect) +ISR(SERIAL_RXD_VECT) { + SERIAL_RXD_INT_ENTER() + + uint8_t data = 0; +#ifdef SERIAL_BIT_ORDER_MSB + uint8_t pos = 0x80; +#else + uint8_t pos = 0x01; +#endif + // to center of start bit + _delay_us(WAIT_US/2); + do { + // to center of next bit + _delay_us(WAIT_US); + + if (SERIAL_RXD_PIN&(1<<SERIAL_RXD_BIT)) { + data |= pos; + } +#ifdef SERIAL_BIT_ORDER_MSB + pos >>= 1; +#else + pos <<= 1; +#endif + } while (pos); + // to center of stop bit + _delay_us(WAIT_US); + +#ifdef SERIAL_NEGATIVE_LOGIC + data = ~data; +#endif + uint8_t next = (rbuf_head + 1) % RBUF_SIZE; if (next != rbuf_tail) { - rbuf[rbuf_head] = SERIAL_RX_DATA; + rbuf[rbuf_head] = data; rbuf_head = next; } + + SERIAL_RXD_INT_EXIT(); } |