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/* Copyright (C) 1994, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Joel Sherrill (jsherril@redstone-emh2.army.mil),
On-Line Applications Research Corporation.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <standalone.h>
#include "i386.h"
/* Console IO routines for a FORCE CPU386 board. */
/* Force CPU/386 specific IO addressing
*
* The following determines whether Port B or the Console should
* be used for console I/O. Setting ONE (and only ONE) of these to 1
* enables I/O on that port.
*
* PORT A - DUSCC MC68562 Channel A (*** not supported here ***)
* PORT B - DUSCC MC68562 Channel B
* PORT C - MFP MC68901 Channel (*** FORCEbug console ***)
*/
#define PORTB 1 /* use port b as console */
#define PORTC 0 /* use console port as console */
#if ( PORTB == 1 )
#define TX_STATUS 0x1b6 /* DUSCC General Status Register */
#define RX_STATUS 0x1b6 /* DUSCC General Status Register */
#define TX_BUFFER 0x1e0 /* DUSCC Transmitter Channel B */
#define RX_BUFFER 0x1e8 /* DUSCC Receiver Channel B */
#define Is_tx_ready( _status ) ( (_status) & 0x20 )
#define Is_rx_ready( _status ) ( (_status) & 0x10 )
#endif
#if ( PORTC == 1 )
#define TX_STATUS 0x12c /* MFP Transmit Status Register */
#define RX_STATUS 0x12a /* MFP Receive Status Register */
#define TX_BUFFER 0x12e /* MFP Transmitter Channel */
#define RX_BUFFER 0x12e /* MFP Receiver Channel */
#define Is_tx_ready( _status ) ( (_status) & 0x80 )
#define Is_rx_ready( _status ) ( (_status) & 0x80 )
#endif
/* _Console_Initialize
On the Force board the console require some initialization. */
void
_Console_Initialize ()
{
register unsigned8 ignored;
/* FORCE technical support mentioned that it may be necessary to
read the DUSCC RX_BUFFER port four times to remove all junk.
This code is a little more paranoid. */
inport_byte( RX_BUFFER, ignored );
inport_byte( RX_BUFFER, ignored );
inport_byte( RX_BUFFER, ignored );
inport_byte( RX_BUFFER, ignored );
inport_byte( RX_BUFFER, ignored );
}
/* Miscellaneous support for console IO */
static inline int _Force386_is_rx_ready ()
{
register unsigned8 status;
inport_byte( RX_STATUS, status );
if ( Is_rx_ready( status ) ) return 1;
else return 0;
}
static inline int _Force386_is_tx_ready ()
{
register unsigned8 status;
inport_byte( TX_STATUS, status );
if ( Is_tx_ready( status ) ) return 1;
else return 0;
}
static inline int _Force386_read_data ()
{
register unsigned8 ch;
#if ( PORTB == 1 )
/* Force example code resets the Channel B Receiver here.
* It appears to cause XON's to be lost.
*/
/* outport_byte( RX_STATUS, 0x10 ); */
#endif
inport_byte( RX_BUFFER, ch );
return ch;
}
/* _Console_Putc
This routine transmits a character. It supports XON/XOFF flow control. */
#define XON 0x11 /* control-Q */
#define XOFF 0x13 /* control-S */
int
_Console_Putc (ch)
char ch;
{
register unsigned8 inch;
while ( !_Force386_is_tx_ready() );
while ( _Force386_is_rx_ready() == 1 ) { /* must be an XOFF */
inch = _Force386_read_data();
if ( inch == XOFF )
do {
while ( _Force386_is_rx_ready() == 0 );
inch = _Force386_read_data();
} while ( inch != XON );
}
outport_byte( TX_BUFFER, ch );
return( 0 );
}
/* _Console_Getc
This routine reads a character from the UART and returns it. */
int
_Console_Getc (poll)
int poll;
{
if ( poll ) {
if ( !_Force386_is_rx_ready() )
return -1;
else
return _Force386_read_data();
} else {
while ( !_Force386_is_rx_ready() );
return _Force386_read_data();
}
}
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