Subversion Repositories NaviCtrl

#include "fifo.h"

#include "main.h"

#include "uart1.h"

u8 fifo_init (fifo_t* f, u8* buffer, const u16 size, u16 putvicsource, u16 getvicsource)

{

        if(f == NULL) return(0);

        f->buffer = buffer;

        f->size = size;

        f->putvicsource = putvicsource;

        f->getvicsource = getvicsource;

        fifo_purge(f);

        return(1);

}

u8 fifo_put(fifo_t *f, const u8 data)

{

        if(f->buffer == 0) return(0);

        if (f->count >= f->size) return(0);     // return 0 in case of FIFO overflow.

        if(f->putvicsource != NO_ITLine) VIC_ITCmd(f->putvicsource, DISABLE);

        *(f->pwrite++) = data;      // copy data byte to buffer

        if(f->pwrite >= f->buffer + f->size) f->pwrite = f->buffer; // start at the begining after reaching the end 

        f->count++;

        if(f->putvicsource != NO_ITLine) VIC_ITCmd(f->putvicsource, ENABLE);

        return(1);

}

u8 fifo_get (fifo_t *f, u8 *pdata)

{

        if(f->buffer == 0) return(0);

        if(!f->count) return(0);

        if(f->getvicsource != NO_ITLine) VIC_ITCmd(f->getvicsource, DISABLE);

        *pdata = *(f->pread++);

        if(f->pread >= f->buffer + f->size) f->pread = f->buffer; // start at the begining after reaching the end 

        f->count--;

        if(f->getvicsource != NO_ITLine) VIC_ITCmd(f->getvicsource, ENABLE);

        return(1);

}

u8 fifo_get_wait (fifo_t *f, u8 *pdata)

{

        while (!f->count);

        return fifo_get(f, pdata);

}

void fifo_purge(fifo_t* f)

{

        if((f == NULL)) return;

        f->count = 0;

        f->pread = f->buffer;

        f->pwrite = f->buffer;

        return;

}