Category : C Source Code
Archive   : MONO.ZIP
Filename : MONODOS.C

// File : MONO.C

// Contents ------------------------------------------------------------------
//
// monoOff Disable the library
// monoOn Enable the library
// mPrint Print a string on the B&W monitor
// mPrintf Print variables using a format on the B&W monitor.
//
// Description
//
// These routines allow a secondary monochrome monitor to be
// used as a debugging screen. These routines are not Windows
// Compatible. See MONODLL.C for Windows Compatible version.
//
// The debug calls can be left in the code
// and a single call to monoOff() will disable all further calls to the
// library. This will allow the calls to be turned back on later and
// also keep the B&W video memory from being written to in case there is
// no B&W monitor in the system and the video memory is being used for
// something else (by a memory manager).
//
// Organization
//
// Interface Dependencies
// Implementation Dependencies
// Global Variables
// Functions
//
// End -----------------------------------------------------------------------

// Interface Dependencies ----------------------------------------------------
#include // for MK_FP
#include "monodos.h"
#include // for vsprintf
#include /* for variable parameter processing */
// End Interface Dependencies ------------------------------------------------

// Implementation Dependencies -----------------------------------------------
#include /* for strlen */

// End Implementation Dependencies -------------------------------------------

// Global Variables ----------------------------------------------------------
static int monitorOff = 0; /* library on or off */
static unsigned int far *screen; /* pointer to B000 */
static int currentLine; /* current line and char positions */
static int currentChar;
// End Global Variables ------------------------------------------------------

// Functions -----------------------------------------------------------------

void
mIncrementLine( void ) {
// Summary -------------------------------------------------------------------
//
// This is a local routine. It increments the current line pointer and
// performs the scroll function if required.
//
// End -----------------------------------------------------------------------

int i;

currentLine++;

/* scroll the screen if required */
if ( currentLine == LPP ) {

/* move lines 2 thru 25 up one line */
for ( i = CPL; i < (CPL*LPP); i++) {
screen[i-CPL] = screen[i];
}
/* clear last line */
for ( i = CPL*(LPP-1); i < (CPL*LPP); i++ ) {
screen[i] = 0x0700 + ' ';
}

/* decrement current line pointer */
currentLine -= 1;
}
}

void
mPrint( int newLine, char far *message ) {
// Summary -------------------------------------------------------------------
//
// This function will display a string on the secondary monitor.
//
// Input Parameters
//
// newLine a true/false parameter used to determine whether a
// CR/LF (newline) is generated after the message is
// displayed on the monitor.
//
// message The character string to be displayed on the monitor.
//
// Remarks
//
// Wrapping is supported and any string that extends past column 80
// is wrapped around. Scrolling is also supported once line 25 is
// is written to.
//
// End -----------------------------------------------------------------------
int i;
int len;
static firstTimeThru = 1;

if ( monitorOff ) return;

/* first time thru, we want to clear the screen.*/
if ( firstTimeThru ) {
firstTimeThru = 0;
screen = (unsigned int far*) MK_FP( 0xB000, 0 );
for ( i = 0; i < (CPL*LPP); i++ ) {
screen[i] = 0x0700 + ' ';
}
currentLine = 0;
currentChar = 0;
}

len = _fstrlen( message );

/* send out the message */
for ( i = 0; i < len; i++ ) {

/* check for word or character wrap */
if ( currentChar == CPL ) {
currentChar = 0;
mIncrementLine();
}
screen[(CPL*currentLine)+currentChar] = 0x0700 + message[i];
currentChar++;
}

/* check on newline generation */
if (newLine == 1) {
currentChar = 0;
mIncrementLine();
}

}

void
mPrintf( int newLine, char *format, ...) {
// Summary -------------------------------------------------------------------
//
// This function displays a formatted string on the secondary monitor
// and accepts the same parameter list as printf.
//
// Input Parameters
//
// newLine a true/false parameter used to determine whether a
// CR/LF (newline) is generated after the message is
// displayed on the monitor.
//
// format,... See printf in the c library.
//
// Remarks
//
// The non parameter formatting strings usable in printf will not work
// the same way on the monochrome monitor. Control codes will be
// displayed as solid squares.
//
// End -----------------------------------------------------------------------
va_list argptr;
char buf[MONOBUFSIZE];

va_start( argptr, format );
vsprintf( buf, format, argptr );
va_end( argptr );

mPrint( newLine, buf );
}

void
monoOn( void )
// Summary -------------------------------------------------------------------
//
// Turn on access to the monochrome monitor.
//
// End -----------------------------------------------------------------------
{
monitorOff = 0;
}

void
monoOff( void )
// Summary -------------------------------------------------------------------
//
// Turn off access to the monochrome monitor.
//
// End -----------------------------------------------------------------------
{
monitorOff = 1;
}

// End of File: MONO.C