/* COMM1190.C
 *
 *
 *      (c) 1998 Micro/sys, Inc.
 *      Glendale, CA
 *      All rights reserved
 *
 * This module contains hardware-specific serial communication example
 * routines for the SBC1190.
 *
 * 8/4/98
 */

#include <stdio.h>
#include <time.h>
#include <dos.h>

#define PCB          0x0FF00        /*  default base address after reset */
 /* serial port registers */
#define B0CMP        PCB+0x060
#define B0CNT        PCB+0x062
#define S0CON        PCB+0x064
#define S0STS        PCB+0x066
#define S0RBUF       PCB+0x068
#define S0TBUF       PCB+0x06A

#define UCSST        PCB+0x0A4        /*  flash */
#define GCS5SP       PCB+0x096
#define GCS0SP       PCB+0x082

#define B9600_12     155
#define B9600_20     259
#define B9600_25     325


#ifdef __TURBOC__
#ifndef inpw
#define inpw            inport
#endif
#ifndef outpw
#define outpw           outport
#endif
#endif

#define SPEEDBYTE       0xE7FD000FL
#define SPEED12MHZ      0xFE
#define SPEED20MHZ      0xFC
#define SPEED25MHZ      0xF8


#define con_txrdy       0x08
#define con_rxrdy       0x40


/*---------------------------------------------------------------------------
 *      uart_transmit
 *
 *      Sends a single character out the COM-B port
 *
 *
 *      On entry:    xmit_char     character to be sent out COM-B
 *
 *      On exit:     -
 *
 *      Returns:     -
 *
 *--------------------------------------------------------------------------*/

int uart_transmit (char xmit_char)
{
	while (!(inp(S0STS) & con_txrdy)) /* wait until UART is ready */
		;

	outp(S0TBUF, xmit_char); /* send the character */

	return (0); /* always return no error */
}

/*---------------------------------------------------------------------------
 *      print2
 *
 *      this routine prints a null-terminated string out the COM-B port
 *
 *
 *      On entry:    prstr      pointer to a null-terminated string
 *
 *      On exit:     -
 *
 *      Returns:     -
 *
 *--------------------------------------------------------------------------*/
void print2(char * prstr)
{
	int n;

	for(n=0; prstr[n]; n++)
	{
		/* change LF to CR-LF */
		if(prstr[n] == '\n')
			uart_transmit('\r');

		uart_transmit(prstr[n]);
	}
}

/*---------------------------------------------------------------------------
 *      getch2
 *
 *      This routine waits for a character to be received in the COM-B
 *      port and returns that character.
 *
 *
 *      On entry:    -
 *
 *      On exit:     -
 *
 *      Returns:     character received in the COM-B port
 *
 *--------------------------------------------------------------------------*/
int getch2(void)
{

	while (!(inp(S0STS) & con_rxrdy)) /* wait for received byte */
		;

	return (inp(S0RBUF)); /* return the received byte */
}

/*---------------------------------------------------------------------------
 *      UnhideFlash
 *
 *      This routine makes the entire flash device visible in the memory
 *      map.  During normal operation, the flash is only visible in the
 *      top 64k of the map (F000:0-F000:FFFF).  In order to access data
 *      in the lower part of the flash, this routine reprograms the
 *      chip-selects so that the flash is visible in the top 512k
 *      (8000:0-F000:FFFF).
 *
 *
 *      On entry:    -
 *
 *      On exit:     -
 *
 *      Returns:     -
 *
 *--------------------------------------------------------------------------*/
void UnhideFlash(void)
{
	/* set UCS start to 8000:0, use previous number of wait-states */
	outpw(UCSST, (inpw(UCSST) & 0x000F) + 0x8000);

	/* disable offboard memory */
	outpw(GCS5SP, 0);

	/* disable socket */
	outpw(GCS0SP, 0);
}

/*---------------------------------------------------------------------------
 *      HideFlash
 *
 *      This routine makes the entire flash device visible in the memory
 *      map.  During normal operation, the flash is only visible in the
 *      top 64k of the map (F000:0-F000:FFFF).  In order to access data
 *      in the lower part of the flash, this routine reprograms the
 *      chip-selects so that the flash is visible in the top 512k
 *      (8000:0-F000:FFFF).
 *
 *
 *      On entry:    -
 *
 *      On exit:     -
 *
 *      Returns:     -
 *
 *--------------------------------------------------------------------------*/
void HideFlash(void)
{
	/* set UCS start to F000:0, use previous number of wait-states */
	outpw(UCSST, (inpw(UCSST) & 0x000F) + 0xF000);

	/* enable offboard memory */
	outpw(GCS5SP, (inp(GCS5SP)& 0x000F) + 0xF000);
}


/*---------------------------------------------------------------------------
 *      GetSpeed
 *
 *      This routine determines the clock speed of the CPU by reading
 *      the byte at E7FD:000F
 *
 *      On entry:    -
 *
 *      On exit:     -
 *
 *      Returns:     SPEED12MHZ    12 MHz CPU clock
 *                   SPEED20MHZ    20 MHz CPU clock
 *                   SPEED25MHZ    25 MHz CPU clock
 *
 *--------------------------------------------------------------------------*/
int GetSpeed(void)
{
	unsigned char far * spdbyteptr;
        int temp;

        UnhideFlash();

	spdbyteptr = (unsigned char far *) SPEEDBYTE;

        temp = ((int)*spdbyteptr);

	HideFlash();

        return (temp);
}


init_comm()
{
	/* initialize COM2 to 9600, 8, 1, N  */

	switch(GetSpeed())
	{
		case SPEED12MHZ:
		default:
			outpw(B0CMP,0x8000+B9600_12);
			break;
		case SPEED20MHZ:
			outpw(B0CMP,0x8000+B9600_20);
			break;
		case SPEED25MHZ:
			outpw(B0CMP,0x8000+B9600_25);
			break;
	}
}

void main(void)
{
	char str[80], key;

	init_comm();

	sprintf(str, "Hello, world!\n");
	print2(str);

	for(;;)
	{
		key = getch2();

		uart_transmit (key);
	}

}