| 0,0 → 1,98 |
|---|
| #ifndef _FIFO_H_ |
| #define _FIFO_H_ |
| |
| #include <avr/io.h> |
| #include <avr/interrupt.h> |
| |
| // the fifo object |
| typedef struct |
| { |
| uint8_t volatile count; // # number of characters in FIFO |
| uint8_t size; // buffer size |
| uint8_t *pread; // read pointer |
| uint8_t *pwrite; // write pointer |
| uint8_t read2end, write2end; // number of characters for buffer overflow for read/write pointers |
| } fifo_t; |
| |
| /* |
| The initialization of the FIFO sets the read/write pointers etc.. |
| The FIFO uses the buffer 'buf' which byte length must 'size'. |
| */ |
| extern void fifo_init (fifo_t*, uint8_t* buf, const uint8_t size); |
| |
| /* |
| Puts a byte into the FIFO. Returns 1 on success ans 0 in case of FIFO overflow. |
| */ |
| extern uint8_t fifo_put (fifo_t*, const uint8_t data); |
| |
| /* |
| Get the next byte out of the FIFO. If the FIFO is empty the function blocks |
| until the next byte is put into the FIFO. |
| */ |
| extern uint8_t fifo_get_wait (fifo_t*); |
| |
| /* |
| Get the next byte from the FIFO as int. Returns -1 if the FIFO is empty. |
| */ |
| extern int16_t fifo_get_nowait (fifo_t*); |
| |
| |
| /* |
| The same like fifo_put |
| */ |
| static inline uint8_t _inline_fifo_put (fifo_t *f, const uint8_t data) |
| { |
| if (f->count >= f->size) |
| return 0; |
| |
| uint8_t * pwrite = f->pwrite; |
| |
| *(pwrite++) = data; |
| |
| uint8_t write2end = f->write2end; |
| |
| if (--write2end == 0) |
| { |
| write2end = f->size; |
| pwrite -= write2end; |
| } |
| |
| f->write2end = write2end; |
| f->pwrite = pwrite; |
| |
| uint8_t sreg = SREG; |
| cli(); |
| f->count++; |
| SREG = sreg; |
| |
| return 1; |
| } |
| |
| /* |
| Get the next byte from FIFO. Before this functionis called |
| it must be checked that there is a byte in the FIFO to get. |
| */ |
| static inline uint8_t _inline_fifo_get (fifo_t *f) |
| { |
| uint8_t *pread = f->pread; |
| uint8_t data = *(pread++); |
| uint8_t read2end = f->read2end; |
| |
| if (--read2end == 0) |
| { |
| read2end = f->size; |
| pread -= read2end; |
| } |
| |
| f->pread = pread; |
| f->read2end = read2end; |
| |
| uint8_t sreg = SREG; |
| cli(); |
| f->count--; |
| SREG = sreg; |
| |
| return data; |
| } |
| |
| #endif /* _FIFO_H_ */ |