Adding a DOS port to run on x86 single board computer.
This commit is contained in:
skarg
@@ -0,0 +1,342 @@
|
||||
/*
|
||||
+----------------------------------------------------+
|
||||
| Thunderbird Software |
|
||||
+----------------------------------------------------+
|
||||
| Filespec : Serial.c |
|
||||
| Date : October 24, 1991 |
|
||||
| Time : 15:03 |
|
||||
| Revision : 1.1 |
|
||||
| Update: August 29, 1994 |
|
||||
+----------------------------------------------------+
|
||||
| Programmer: Scott Andrews |
|
||||
| Address : 5358 Summit RD SW |
|
||||
| City/State: Pataskala, Ohio |
|
||||
| Zip : 43062 |
|
||||
+----------------------------------------------------+
|
||||
| Released to the Public Domain |
|
||||
+----------------------------------------------------+
|
||||
*/
|
||||
|
||||
/*
|
||||
+----------------------------------------------------------+
|
||||
| Call open_serial to install the interrupt handler |
|
||||
| You must call close_serial before exiting your program |
|
||||
| or a machine crash will occur! |
|
||||
+----------------------------------------------------------+
|
||||
*/
|
||||
|
||||
#include <stdlib.h>
|
||||
#include <dos.h>
|
||||
#include <string.h>
|
||||
#include "serial.h"
|
||||
#include "queue.h"
|
||||
|
||||
QUEUE *Serial_In_Queue;
|
||||
QUEUE *Serial_Out_Queue;
|
||||
|
||||
OLD_COMM_PARAMS old_comm_params;
|
||||
COMM_STATUS comm_status;
|
||||
|
||||
void (INTERRUPT FAR *oldvector_serial )();
|
||||
/* save addr for intr handler */
|
||||
|
||||
int ComBase; /* Comm port address */
|
||||
int IrqNum; /* Comm interrupt request */
|
||||
|
||||
int OpenComPort ( char Port ) /* install int. handler */
|
||||
{
|
||||
unsigned status;
|
||||
int retval = -1;
|
||||
|
||||
/* allocate input and output queues */
|
||||
|
||||
Serial_In_Queue = alloc_queue( SerInBufSize );
|
||||
if ( (QUEUE *) 0 == Serial_In_Queue)
|
||||
return retval;
|
||||
Serial_Out_Queue = alloc_queue( SerOutBufSize );
|
||||
if ( (QUEUE *) 0 == Serial_Out_Queue)
|
||||
{
|
||||
free ( Serial_In_Queue );
|
||||
return retval;
|
||||
}
|
||||
retval = 0;
|
||||
|
||||
/* Setup Comm base port address and IRQ number */
|
||||
|
||||
switch ( Port)
|
||||
{
|
||||
case '1': ComBase = 0x3F8; IrqNum = 4; break;
|
||||
case '2': ComBase = 0x2F8; IrqNum = 3; break;
|
||||
case '3': ComBase = 0x3E8; IrqNum = 4; break;
|
||||
case '4': ComBase = 0x2E8; IrqNum = 3; break;
|
||||
default : ComBase = 0x3F8; IrqNum = 4; break;
|
||||
}
|
||||
old_comm_params.int_enable = inp ( ComBase + INT_EN );
|
||||
outp ( ComBase + INT_EN, 0 ); /* turn off comm interrupts */
|
||||
|
||||
/* save old comm parameters */
|
||||
|
||||
old_comm_params.line = inp ( ComBase + LINE_CNTRL );
|
||||
old_comm_params.modem = inp ( ComBase + MODEM_CNTRL );
|
||||
status = inp ( ComBase + LINE_CNTRL );
|
||||
outp ( ComBase + LINE_CNTRL, (unsigned char) status | 0x80 );
|
||||
old_comm_params.baud_lsb = inp ( ComBase + BAUD_LSB );
|
||||
old_comm_params.baud_msb = inp ( ComBase + BAUD_MSB );
|
||||
status = inp ( ComBase + LINE_CNTRL );
|
||||
outp ( ComBase + LINE_CNTRL, (unsigned char) status | 0x7F );
|
||||
status = OUT2 | DTR; /* DTR/OUT2 must be set! */
|
||||
outp ( ComBase + MODEM_CNTRL, (unsigned char) status );
|
||||
|
||||
/* get serial port address/vector */
|
||||
|
||||
oldvector_serial = (void(INTERRUPT FAR *)(void))getvect(IrqNum + 8 );
|
||||
|
||||
/* set our interrupt handler */
|
||||
|
||||
setvect ( IrqNum + 8, serial );
|
||||
|
||||
/* save the PIC */
|
||||
|
||||
old_comm_params.int_cntrl = inp ( 0x21 );
|
||||
status = ( 1 << IrqNum); /* calculate int enable bit */
|
||||
status = ~status;
|
||||
|
||||
/* ok enable comm ints */
|
||||
|
||||
outp ( 0x21, (unsigned char) old_comm_params.int_cntrl &
|
||||
(unsigned char) status );
|
||||
return retval;
|
||||
}
|
||||
|
||||
void CloseComPort ( void )
|
||||
{
|
||||
int status;
|
||||
|
||||
/* restore UART to previous state */
|
||||
|
||||
outp ( ComBase + INT_EN, (unsigned char) 0 );
|
||||
outp ( ComBase + MODEM_CNTRL,
|
||||
(unsigned char) old_comm_params.modem );
|
||||
status = inp ( ComBase + LINE_CNTRL );
|
||||
outp ( ComBase + LINE_CNTRL,
|
||||
(unsigned char) status | 0x80 );
|
||||
outp ( ComBase + BAUD_LSB,
|
||||
(unsigned char) old_comm_params.baud_lsb );
|
||||
outp ( ComBase + BAUD_MSB,
|
||||
(unsigned char) old_comm_params.baud_msb );
|
||||
outp ( ComBase + LINE_CNTRL,
|
||||
(unsigned char) old_comm_params.line );
|
||||
outp ( 0x21, (unsigned char) old_comm_params.int_cntrl );
|
||||
|
||||
/* restore old interrupt handler */
|
||||
|
||||
setvect ( IrqNum + 8, oldvector_serial );
|
||||
|
||||
/* free input and output queues */
|
||||
|
||||
free ( Serial_In_Queue );
|
||||
free ( Serial_Out_Queue );
|
||||
return;
|
||||
}
|
||||
|
||||
void InitComPort ( char Baud[], char Databits,
|
||||
char Parity, char Stopbits )
|
||||
{
|
||||
int status;
|
||||
long baudrate;
|
||||
unsigned divisor;
|
||||
|
||||
/* set baud rate */
|
||||
|
||||
status = inp ( ComBase + LINE_CNTRL );
|
||||
outp ( ComBase + LINE_CNTRL,
|
||||
(unsigned char) status | 0x80 );
|
||||
baudrate = atol ( Baud );
|
||||
if ( baudrate == 0)
|
||||
baudrate = 2400L;
|
||||
divisor = (unsigned) ( 115200L / baudrate);
|
||||
outp ( ComBase + BAUD_LSB,
|
||||
(unsigned char) ( divisor & 0x00FF) );
|
||||
outp ( ComBase + BAUD_MSB,
|
||||
(unsigned char) ( ( divisor >> 8) & 0x00FF) );
|
||||
status = 0x00;
|
||||
|
||||
/* set parity */
|
||||
|
||||
switch ( Parity) /* set parity value */
|
||||
{
|
||||
case 'O': /* odd parity */
|
||||
case 'o':
|
||||
status = 0x08; break;
|
||||
|
||||
case 'E': /* even parity */
|
||||
case 'e':
|
||||
status = 0x18; break;
|
||||
|
||||
case 'S': /* stick parity */
|
||||
case 's':
|
||||
status = 0x28; break;
|
||||
|
||||
case 'N': /* no parity */
|
||||
case 'n':
|
||||
default : status = 0x00;
|
||||
}
|
||||
|
||||
/* set number data bits */
|
||||
|
||||
switch ( Databits)
|
||||
{
|
||||
case '5':
|
||||
break;
|
||||
|
||||
case '6':
|
||||
status = status | 0x01;
|
||||
break;
|
||||
|
||||
case '7':
|
||||
status = status | 0x02;
|
||||
break;
|
||||
|
||||
case '8':
|
||||
default :
|
||||
status = status | 0x03;
|
||||
}
|
||||
|
||||
/* set number stop bits */
|
||||
|
||||
switch ( Stopbits)
|
||||
{
|
||||
case '2':
|
||||
status = status | 0x04;
|
||||
break;
|
||||
|
||||
case '1':
|
||||
default :
|
||||
;
|
||||
}
|
||||
outp ( ComBase + LINE_CNTRL, (unsigned char) status );
|
||||
status = OUT2 | DTR; /* DTR/OUT2 must be set! */
|
||||
outp ( ComBase + MODEM_CNTRL, (unsigned char) status );
|
||||
|
||||
/* enable serial interrupts */
|
||||
|
||||
outp ( ComBase + INT_EN, RX_INT | ERR_INT | RS_INT );
|
||||
return;
|
||||
}
|
||||
|
||||
void DropDtr ( void )
|
||||
{
|
||||
int status;
|
||||
|
||||
status = inp ( ComBase + MODEM_CNTRL );
|
||||
status &= 0xFE; /* turn off DTR bit */
|
||||
outp ( ComBase + MODEM_CNTRL, (unsigned char) status );
|
||||
return;
|
||||
}
|
||||
|
||||
void RaiseDtr ( void )
|
||||
{
|
||||
int status;
|
||||
|
||||
status = inp ( ComBase + MODEM_CNTRL );
|
||||
status |= 0x01; /* turn on DTR bit */
|
||||
outp ( ComBase + MODEM_CNTRL, (unsigned char) status );
|
||||
return;
|
||||
}
|
||||
|
||||
int ComRecChar ( void )
|
||||
{
|
||||
return de_queue ( Serial_In_Queue );
|
||||
}
|
||||
|
||||
int ComSendString ( char *string )
|
||||
{
|
||||
int retval;
|
||||
char *pointer;
|
||||
pointer = string;
|
||||
|
||||
while ( *pointer)
|
||||
{
|
||||
retval = en_queue ( Serial_Out_Queue, *pointer );
|
||||
pointer++;
|
||||
}
|
||||
if ( 0x0 == (comm_status.modem & 0x40))
|
||||
RaiseDtr ();
|
||||
outp ( ComBase + INT_EN, RX_INT | TBE_INT | ERR_INT | RS_INT );
|
||||
return retval;
|
||||
}
|
||||
|
||||
int ComSendChar ( char character )
|
||||
{
|
||||
int retval;
|
||||
|
||||
/* interrupt driven send */
|
||||
|
||||
if ( 0x0 == (comm_status.modem & 0x40))
|
||||
RaiseDtr ();
|
||||
retval = en_queue ( Serial_Out_Queue, character );
|
||||
if ( - 1 != retval)
|
||||
outp ( ComBase + INT_EN, RX_INT | TBE_INT | ERR_INT | RS_INT );
|
||||
return retval;
|
||||
}
|
||||
|
||||
int ComStatus ( void )
|
||||
{
|
||||
unsigned status;
|
||||
unsigned retval;
|
||||
|
||||
retval = inp ( ComBase + LINE_STATUS );
|
||||
retval = retval << 8;
|
||||
status = inp ( ComBase + MODEM_STATUS );
|
||||
retval = retval | status;
|
||||
if ( queue_empty ( Serial_In_Queue ))
|
||||
retval &= 0xFEFF;
|
||||
else retval |= 0x0100;
|
||||
return (int) retval;
|
||||
}
|
||||
|
||||
void INTERRUPT FAR serial ( void ) /* interrupt handler */
|
||||
{
|
||||
int temp;
|
||||
|
||||
disable ();
|
||||
while ( 1)
|
||||
{
|
||||
comm_status.intrupt = inp ( ComBase + INT_ID );
|
||||
comm_status.intrupt &= 0x0f;
|
||||
switch ( comm_status.intrupt)
|
||||
{
|
||||
case 0x00: /* modem interrupt */
|
||||
comm_status.modem = inp( ComBase + MODEM_STATUS );
|
||||
break;
|
||||
|
||||
case 0x02: /* xmit interrupt */
|
||||
if ( queue_empty ( Serial_Out_Queue ))
|
||||
outp(ComBase + INT_EN, RX_INT|ERR_INT|RS_INT );
|
||||
else
|
||||
{
|
||||
temp = de_queue ( Serial_Out_Queue );
|
||||
if ( - 1 != temp)
|
||||
outp ( ComBase + XMIT, temp );
|
||||
}
|
||||
break;
|
||||
|
||||
case 0x04: /* receive interrupt */
|
||||
en_queue(Serial_In_Queue, (char)inp(ComBase + REC));
|
||||
break;
|
||||
|
||||
case 0x06: /* line interrupt */
|
||||
comm_status.line = inp ( ComBase + LINE_STATUS );
|
||||
(void) inp ( ComBase + REC );
|
||||
en_queue ( Serial_In_Queue, '!' );
|
||||
break;
|
||||
|
||||
default: /* No Mo` Left */
|
||||
comm_status.modem = inp ( ComBase + MODEM_STATUS );
|
||||
outp ( 0x20, 0x20 );
|
||||
enable ();
|
||||
return;
|
||||
} /* switch */
|
||||
} /* while */
|
||||
}
|
||||
/* End of Serial.C */
|
||||
Reference in New Issue
Block a user