65 lines
1.9 KiB
C
65 lines
1.9 KiB
C
|
//rbuf.c
|
||
|
|
#include "rbuf.h"
|
||
|
|
//#include <avr/interrupt.h>
|
||
|
|
|
||
|
|
|
||
|
|
void rbuf_ini(uint8_t* ptr, uint8_t l)
|
||
|
|
{
|
||
|
|
ptr[0] = l;
|
||
|
|
ptr[1] = 0;
|
||
|
|
ptr[2] = 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
//lock/unlock macros
|
||
|
|
//#define _lock() uint8_t _sreg = SREG; cli();
|
||
|
|
//#define _unlock() SREG = _sreg;
|
||
|
|
#define _lock()
|
||
|
|
#define _unlock()
|
||
|
|
|
||
|
|
//put single byte to buffer
|
||
|
|
int rbuf_put(uint8_t* ptr, uint8_t b)
|
||
|
|
{
|
||
|
|
//#ifdef _NO_ASM
|
||
|
|
_lock(); //lock
|
||
|
|
uint8_t buf_w = ptr[1]; //get write index
|
||
|
|
uint8_t buf_r = ptr[2]; //get read index
|
||
|
|
_unlock(); //unlock
|
||
|
|
ptr[4 + buf_w] = b; //store byte to buffer
|
||
|
|
buf_w++; //incerment write index
|
||
|
|
uint8_t buf_l = ptr[0]; //get length
|
||
|
|
if (buf_w >= buf_l) buf_w = 0; //rotate write index
|
||
|
|
if (buf_w == buf_r) return -1; //return -1 to signal buffer full
|
||
|
|
ptr[1] = buf_w; //store write index
|
||
|
|
return 0; //return 0 to signal success
|
||
|
|
//#else //_NO_ASM
|
||
|
|
// TODO - optimized assembler version
|
||
|
|
// asm("movw r26, r24");
|
||
|
|
// asm("ld r18, X+");
|
||
|
|
// asm("cli");
|
||
|
|
// asm("ld r19, X+");
|
||
|
|
// asm("ld r20, X");
|
||
|
|
// asm("cp r19, r18");
|
||
|
|
// asm("brne .-6");*/
|
||
|
|
//#endif //_NO_ASM
|
||
|
|
}
|
||
|
|
|
||
|
|
//get single byte from buffer
|
||
|
|
int rbuf_get(uint8_t* ptr)
|
||
|
|
{
|
||
|
|
//#ifdef _NO_ASM
|
||
|
|
_lock(); //lock
|
||
|
|
uint8_t buf_w = ptr[1]; //get write index
|
||
|
|
uint8_t buf_r = ptr[2]; //get read index
|
||
|
|
_unlock(); //unlock
|
||
|
|
if (buf_r == buf_w) return -1; //return -1 to signal buffer empty
|
||
|
|
int ret = ptr[4 + buf_r]; //get byte from buffer
|
||
|
|
buf_r++; //increment read index
|
||
|
|
uint8_t buf_l = ptr[0]; //get length
|
||
|
|
if (buf_r >= buf_l) buf_r = 0; //rotate read index
|
||
|
|
ptr[2] = buf_r; //store read index
|
||
|
|
return ret; //return byte (0-255)
|
||
|
|
// return 0; //return 0 to signal success
|
||
|
|
//#else //_NO_ASM
|
||
|
|
// TODO - optimized assembler version
|
||
|
|
//#endif //_NO_ASM
|
||
|
|
}
|