jd5xxevm.c

EVM板JPEG实现,Texas Instruments TMS320C54x EVM JPEG

/*********************************************************************
*       (C) COPYRIGHT TEXAS INSTRUMENTS, INC. 1996                   *
**********************************************************************/
/* jd5xxevm.c
 * 'C54x EVM JPEG Decompression - EVM Functions
 * This file contains all functions used by the EVM to communicate
 * with the host.
 *
 * Kamal Swamidoss
 * Texas Instruments
 * 4 July 1996
 */

#include "jd5xx.h"

/* EVM I/O addresses for PC/EVM interface (see EVM Tech. Ref. p.3-7) */
ioport unsigned int port10;         /* EVM channel A   */
ioport          int port12;         /* EVM channel B   */
ioport unsigned int port14;         /* EVM status reg. */

void send_command(unsigned int);

void initialize(void)
{
   asm("init1  XC 2,BIO ");
   asm("       B  init1 ");
   asm("init2  XC 2,NBIO");
   asm("       B  init2 ");
   asm("init3  XC 2,BIO ");
   asm("       B  init3 ");
	send_command(ACK);
}

void send_command(unsigned int cmd)
{
	port10 = cmd;
	while (axst());
}

void send_data(int data)
{
	port12 = data;
}

int receive_data(void)
{
   int tmp;
	tmp = port12;
	return(tmp);
}

unsigned int receive_command(void)
{
   unsigned int tmp;
   while (!arst());
   tmp = port10;
	return(tmp);
}

int axst(void)
{
	unsigned int tmp;
	tmp = port14;
	tmp = tmp & AXST;

	if (tmp == AXST)
		return(1);

	return(0);
}

int arst(void)
{
   unsigned int tmp;
   tmp = port14;
	tmp = tmp & ARST;

	if (tmp == ARST)
		return(1);

	return(0);
}