rott/rottcom/ROTTSER/PORT.C
2002-12-25 00:00:00 +00:00

632 lines
12 KiB
C

/*
Copyright (C) 1994-1995 Apogee Software, Ltd.
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
// port.c
#include "global.h"
#include "port.h"
#include "serial.h"
#include "sercom.h"
#include "sersetup.h"
#include <conio.h>
#include <dos.h>
#include <stdio.h>
#include <stdlib.h>
#include <mem.h>
union REGS regs;
struct SREGS sregs;
que_t inque, outque;
int irq = -1;
int uart = -1;
int comport = -1;
long baudrate = 9600;
enum {UART_8250, UART_16550} uart_type;
int modem_status = -1;
int line_status = -1;
void interrupt (far *oldirqvect) (void);
int irqintnum;
/*
===============
=
= Is8250
=
===============
*/
boolean Is8250 ( void )
{
return (uart_type == UART_8250);
}
/*
==============
=
= GetUart
=
==============
*/
void GetUart ( void )
{
char far *system_data;
static int ISA_uarts[] = {0x3f8,0x2f8,0x3e8,0x2e8};
static int ISA_IRQs[] = {4,3,4,3};
static int MCA_uarts[] = {0x03f8,0x02f8,0x3220,0x3228};
static int MCA_IRQs[] = {4,3,3,3};
regs.h.ah = 0xc0;
int86x( 0x15, &regs, &regs, &sregs );
if ( regs.x.cflag )
{
if (irq == -1)
irq = ISA_IRQs[ comport-1 ];
if (uart == -1)
uart = ISA_uarts[ comport-1 ];
return;
}
system_data = ( char far *) ( ( (long) sregs.es << 16 ) + regs.x.bx );
if ( system_data[ 5 ] & 0x02 )
{
if (irq == -1)
irq = MCA_IRQs[ comport-1 ];
if (uart == -1)
uart = MCA_uarts[ comport-1 ];
}
else
{
if (irq == -1)
irq = ISA_IRQs[ comport-1 ];
if (uart == -1)
uart = ISA_uarts[ comport-1 ];
}
printf ("Looking for UART at port 0x%x, irq %d...\n",uart,irq);
}
/*
===============
=
= InitPort
=
===============
*/
void InitPort ( void )
{
int mcr;
int temp;
unsigned long divisor;
//
// init com port settings
//
/*******
regs.x.ax = 0xf3; //f3= 9600 n 8 1
regs.x.dx = comport - 1;
int86 (0x14, &regs, &regs);
*******/
inque.head=0;
inque.tail=0;
inque.size=0;
outque.head=0;
outque.tail=0;
outque.size=0;
printf ("Port Speed = %ld\n",baudrate);
divisor = baudrate;
//
// check for a 16550
//
OUTPUT( uart + FIFO_CONTROL_REGISTER, FCR_FIFO_ENABLE + FCR_TRIGGER_04 );
temp = INPUT( uart + INTERRUPT_ID_REGISTER );
if ( ( temp & 0xf8 ) == 0xc0 )
{
uart_type = UART_16550;
printf ("UART is a 16550\n");
}
else
{
uart_type = UART_8250;
OUTPUT( uart + FIFO_CONTROL_REGISTER, 0 );
printf ("UART is an 8250\n");
if (divisor>57600L)
{
divisor=57600L;
printf("WARNING: The 8250 cannot handle port speeds above 57,600\n"
" Setting port speed to 57,600.\n");
}
// printf("\nSorry, Rise of the Triad currently does not support 8250 UARTS.\n");
// printf("This will be corrected in version 1.1.\n");
// ShutDown();
// exit(0);
}
// if ((divisor = baudrate) == 14400)
// divisor = 19200;
divisor = CLOCK_FREQUENCY / (16 * divisor); /* Calc. divisor */
OUTPUT( uart + LINE_CONTROL_REGISTER, LCR_DLAB ); /* Enable divisor */
OUTPUT( uart + DIVISOR_LATCH_HIGH, 0 ); /* Set divisor */
OUTPUT( uart + DIVISOR_LATCH_LOW, (unsigned char) divisor);
OUTPUT( uart + LINE_CONTROL_REGISTER, 3 ); /* Set 8,n,1 */
//
// prepare for interrupts
//
OUTPUT( uart + INTERRUPT_ENABLE_REGISTER, 0 ); /* Turn off interrupts */
mcr = INPUT( uart + MODEM_CONTROL_REGISTER ); /* Get modem status */
mcr |= MCR_OUT2; /* Set GPO 2 */
mcr &= ~MCR_LOOPBACK; /* Turn off loopback test */
mcr |= MCR_DTR; /* Set DTR */
mcr |= MCR_RTS; /* Set RTS */
OUTPUT( uart + MODEM_CONTROL_REGISTER, mcr ); /* Set modem status */
INPUT( uart ); /* Clear Rx interrupts */
INPUT( uart + INTERRUPT_ID_REGISTER ); /* Clear Tx interrupts */
//
// hook the irq vector
//
irqintnum = irq + 8;
oldirqvect = getvect (irqintnum);
setvect (irqintnum,isr_8250);
#if 0
if( uart_type == UART_8250 ) /* Use different interrupt routines */
setvect (irqintnum, isr_8250);
else
setvect (irqintnum, isr_16550);
#endif
OUTPUT( 0x20 + 1, INPUT( 0x20 + 1 ) & ~(1<<irq) );
CLI();
// enable RX and TX interrupts at the uart
// also enable Line Status interrupts to watch for errors.
OUTPUT( uart + INTERRUPT_ENABLE_REGISTER,
IER_RX_DATA_READY + IER_TX_HOLDING_REGISTER_EMPTY);// + IER_LINE_STATUS );
// enable interrupts through the interrupt controller
OUTPUT( 0x20, 0xc2 );
// Set DTR
OUTPUT( uart + MODEM_CONTROL_REGISTER,
INPUT( uart + MODEM_CONTROL_REGISTER ) | MCR_DTR );
STI();
}
/*
=============
=
= ShutdownPort
=
=============
*/
void ShutdownPort ( void )
{
OUTPUT( uart + INTERRUPT_ENABLE_REGISTER, 0 ); /* Turn off interrupts */
OUTPUT( uart + MODEM_CONTROL_REGISTER, 0 ); /* Clear modem status */
OUTPUT( uart + FIFO_CONTROL_REGISTER, 0 ); /* Clear fifo status */
OUTPUT( 0x20 + 1, INPUT( 0x20 + 1 ) | (1<<irq) );
setvect (irqintnum,oldirqvect); /* Return to orig. inter. */
}
int read_byte( void )
{
int c;
if (inque.size == 0)
return -1;
c = inque.data[QueSpot(inque.tail++)];
inque.size--;
return c;
}
void write_byte( unsigned char c )
{
outque.data[QueSpot(outque.head++)] = c;
outque.size++;
if ( INPUT( uart + LINE_STATUS_REGISTER ) & 0x40)
jump_start();
}
void write_bytes( char *buf, int count )
{
if (QueSpot(outque.head) + count >= QUESIZE) /* About to wrap around */
{
while (count--)
write_byte (*buf++);
}
else
{
memcpy(outque.data + QueSpot(outque.head), buf, count); /* Write all at once */
outque.head += count;
outque.size += count;
if ( INPUT( uart + LINE_STATUS_REGISTER ) & 0x40)
jump_start();
}
}
/*
================
=
= write_buffer
=
================
*/
void write_buffer( char *buffer, unsigned int count )
{
// if this would overrun the buffer, throw everything else out
if (outque.size + count > QUESIZE)
{
++writeBufferOverruns;
outque.tail = outque.head;
outque.size = 0;
}
write_bytes (buffer, count);
}
/*
==============
=
= isr_8250
=
==============
*/
void interrupt isr_8250(void)
{
int c;
int count;
OUTPUT( 0x20, 0x20 );
while (1)
{
switch( INPUT( uart + INTERRUPT_ID_REGISTER ) & 7 )
{
//
// receive one byte for the UART 8250,
// as many as possible for the UART 16550
//
case IIR_RX_DATA_READY_INTERRUPT :
++numRxInterrupts;
do
{
c = INPUT( uart + RECEIVE_BUFFER_REGISTER );
inque.data[QueSpot(inque.head++)] = c;
inque.size++;
} while ( uart_type == UART_16550 && INPUT( uart + LINE_STATUS_REGISTER ) & LSR_DATA_READY );
break;
//
// transmit one byte for the UART 8250
// 16 bytes for the UART 16550
//
case IIR_TX_HOLDING_REGISTER_INTERRUPT :
++numTxInterrupts;
if (outque.size != 0)
{
if (uart_type == UART_16550)
count = 16;
else
count = 1;
do
{
c = outque.data[QueSpot(outque.tail++)];
outque.size--;
OUTPUT( uart + TRANSMIT_HOLDING_REGISTER, c );
} while (--count && outque.size != 0);
}
break;
case IIR_MODEM_STATUS_INTERRUPT :
modem_status = INPUT( uart + MODEM_STATUS_REGISTER );
break;
// not enabled
case IIR_LINE_STATUS_INTERRUPT :
line_status = INPUT( uart + LINE_STATUS_REGISTER );
if ( line_status & LSR_OVERRUN_ERROR )
++numOverrunError;
if ( line_status & LSR_PARITY_ERROR )
++numParityError;
if ( line_status & LSR_FRAMING_ERROR )
++numFramingError;
if ( line_status & LSR_BREAK_DETECT )
++numBreak;
break;
//
// done
//
default :
return;
}
}
}
/*
===============
=
= jump_start
=
= Start up the transmition interrupts by sending the first char
===============
*/
void jump_start( void )
{
int c;
if (outque.size != 0)
{
c = outque.data [QueSpot(outque.tail++)];
outque.size--;
OUTPUT( uart, c );
}
}
#if 0
//==========================================================================
/*
==============
=
= isr_8250
=
==============
*/
void interrupt isr_8250(void)
{
int c;
int count;
while (1)
{
switch( INPUT( uart + INTERRUPT_ID_REGISTER ) & 7 )
{
//
// receive exactly one byte, since this is a UART 8250
//
case IIR_RX_DATA_READY_INTERRUPT :
//I_ColorBlack (0,63,0);
++numRxInterrupts;
c = INPUT( uart + RECEIVE_BUFFER_REGISTER );
inque.data[QueSpot(inque.head++)] = c;
inque.size++;
// if (inque.head >= QUESIZE)
// inque.head = 0; // wrap around
break;
//
// transmit exactly one byte, since this is a UART 8250
//
case IIR_TX_HOLDING_REGISTER_INTERRUPT :
//I_ColorBlack (63,0,0);
++numTxInterrupts;
if (outque.size != 0)
{
c = outque.data[QueSpot(outque.tail++)];
outque.size--;
// if (outque.tail >= QUESIZE)
// outque.tail = 0; // wrap around
OUTPUT( uart + TRANSMIT_HOLDING_REGISTER, c );
}
break;
#if 0 // not enabled
* case IIR_MODEM_STATUS_INTERRUPT :
* modem_status = INPUT( uart + MODEM_STATUS_REGISTER );
* break;
#endif
//
// line status
//
case IIR_LINE_STATUS_INTERRUPT :
line_status = INPUT( uart + LINE_STATUS_REGISTER );
if ( line_status & LSR_OVERRUN_ERROR )
++numOverrunError;
if ( line_status & LSR_PARITY_ERROR )
++numParityError;
if ( line_status & LSR_FRAMING_ERROR )
++numFramingError;
if ( line_status & LSR_BREAK_DETECT )
++numBreak;
break;
//
// done
//
default :
//I_ColorBlack (0,0,0);
OUTPUT( 0x20, 0x20 );
return;
}
}
}
//==========================================================================
/*
==============
=
= isr_16550
=
==============
*/
void interrupt isr_16550(void)
{
int c;
int count;
while (1)
{
switch( INPUT( uart + INTERRUPT_ID_REGISTER ) & 7 )
{
//
// receive
//
case IIR_RX_DATA_READY_INTERRUPT :
//I_ColorBlack (0,63,0);
++numRxInterrupts;
do
{
c = INPUT( uart + RECEIVE_BUFFER_REGISTER );
inque.data[QueSpot(inque.head++)] = c;
inque.size++;
// if (inque.head >= QUESIZE)
// inque.head = 0; // wrap around
} while ( INPUT( uart + LINE_STATUS_REGISTER ) & LSR_DATA_READY );
break;
//
// transmit
//
case IIR_TX_HOLDING_REGISTER_INTERRUPT :
//I_ColorBlack (63,0,0);
++numTxInterrupts;
if (outque.size != 0)
{
count = 16;
do
{
c = outque.data[QueSpot(outque.tail++)];
outque.size--;
// if (outque.tail >= QUESIZE)
// outque.tail = 0; // wrap around
OUTPUT( uart + TRANSMIT_HOLDING_REGISTER, c );
} while (--count && outque.size != 0);
}
break;
#if 0 // not enabled
* case IIR_MODEM_STATUS_INTERRUPT :
* modem_status = INPUT( uart + MODEM_STATUS_REGISTER );
* break;
#endif
//
// line status
//
case IIR_LINE_STATUS_INTERRUPT :
line_status = INPUT( uart + LINE_STATUS_REGISTER );
if ( line_status & LSR_OVERRUN_ERROR )
++numOverrunError;
if ( line_status & LSR_PARITY_ERROR )
++numParityError;
if ( line_status & LSR_FRAMING_ERROR )
++numFramingError;
if ( line_status & LSR_BREAK_DETECT )
++numBreak;
break;
//
// done
//
default :
//I_ColorBlack (0,0,0);
OUTPUT( 0x20, 0x20 );
return;
}
}
}
#endif