sipo.c

Go to the documentation of this file.

#include "sipo.h"

#include "hw/hw_sipo.h"

#include <cfg/compiler.h>

#include <kern/kfile.h>

#include <string.h>

INLINE void sipo_putchar(uint8_t c)
{
    for(int i = 0; i < 8; i++)
    {
        if((c & BV(i)) == 0)
            SIPO_SI_LOW();
        else
            SIPO_SI_HIGH();

        SIPO_SI_CLOCK();
    }
}

 static size_t sipo_write(UNUSED_ARG(struct KFile *, fd), const void *_buf, size_t size)
{
    const uint8_t *buf = (const uint8_t *)_buf;
    size_t write_len = size;
    ASSERT(buf);

    // Load into the shift register all the buffer bytes
    while(size--)
        sipo_putchar(*buf++);

    // We have just finished to shift the bytes into the register, now load them.
    SIPO_LOAD();

    return write_len;
}

void sipo_init(Sipo *fd)
{
    ASSERT(fd);

    memset(fd, 0, sizeof(Sipo));

    //Set kfile struct type as a Sipo structure.
    DB(fd->fd._type = KFT_SIPO);

    // Set up SIPO writing functions.
    fd->fd.write = sipo_write;

    SIPO_INIT_PIN();

}