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QWIKC SCREEN UTILITIES REFERENCE GUIDE Version 2.1 June 1, 1989 Conversion to Turbo C / MS C by Jordan Gallagher / Wisdom Research Copyright (C) 1988,1989 Eagle Performance Software All Rights Reserved. _______ ____|__ | (tm) --| | |------------------- | ____|__ | Association of | | |_| Shareware |__| o | Professionals -----| | |--------------------- |___|___| MEMBER QWIKC Screen Utilities Reference Guide, Version 2.1 T A B L E O F C O N T E N T S 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . 3 Purpose . . . . . . . . . . . . . . . . . . . . . . . 3 Common Parameters . . . . . . . . . . . . . . . . . . 3 Attributes . . . . . . . . . . . . . . . . . . . . . 4 2. FUNCTIONS . . . . . . . . . . . . . . . . . . . . . . . 6 eosc . . . . . . . . . . . . . . . . . . . . . . . . 6 eosln . . . . . . . . . . . . . . . . . . . . . . . . 6 eosr . . . . . . . . . . . . . . . . . . . . . . . . 6 eostocursor . . . . . . . . . . . . . . . . . . . . . 6 eostorc . . . . . . . . . . . . . . . . . . . . . . . 7 eostorcrel . . . . . . . . . . . . . . . . . . . . . 7 getcursor . . . . . . . . . . . . . . . . . . . . . . 7 get_submodel_id . . . . . . . . . . . . . . . . . . . 7 gotoeos . . . . . . . . . . . . . . . . . . . . . . . 8 gotorc. . . . . . . . . . . . . . . . . . . . . . . . 8 modcursor . . . . . . . . . . . . . . . . . . . . . . 8 qattr . . . . . . . . . . . . . . . . . . . . . . . . 9 qattrc . . . . . . . . . . . . . . . . . . . . . . . 9 qattreos . . . . . . . . . . . . . . . . . . . . . . 9 qeosln . . . . . . . . . . . . . . . . . . . . . . . 10 qfill . . . . . . . . . . . . . . . . . . . . . . . . 10 qfillc . . . . . . . . . . . . . . . . . . . . . . . 10 qfilleos . . . . . . . . . . . . . . . . . . . . . . 11 qinit . . . . . . . . . . . . . . . . . . . . . . . . 11 qreadattr . . . . . . . . . . . . . . . . . . . . . . 12 qreadchar . . . . . . . . . . . . . . . . . . . . . . 12 qreadstr . . . . . . . . . . . . . . . . . . . . . . 12 qreinit . . . . . . . . . . . . . . . . . . . . . . . 12 qscrolldown . . . . . . . . . . . . . . . . . . . . . 13 qscrollup . . . . . . . . . . . . . . . . . . . . . . 13 qscrtovscr . . . . . . . . . . . . . . . . . . . . . 14 qstoretomem . . . . . . . . . . . . . . . . . . . . . 15 qstoretoscr . . . . . . . . . . . . . . . . . . . . . 15 qviewpage . . . . . . . . . . . . . . . . . . . . . . 16 qvscrtoscr . . . . . . . . . . . . . . . . . . . . . 17 qwrite . . . . . . . . . . . . . . . . . . . . . . . 18 qwritec . . . . . . . . . . . . . . . . . . . . . . . 18 qwriteeos . . . . . . . . . . . . . . . . . . . . . . 19 qwriteeos_sub . . . . . . . . . . . . . . . . . . . . 19 qwritepage . . . . . . . . . . . . . . . . . . . . . 19 qwrite_sub . . . . . . . . . . . . . . . . . . . . . 20 setcursor . . . . . . . . . . . . . . . . . . . . . . 20 setmultitask . . . . . . . . . . . . . . . . . . . . 21 wherec . . . . . . . . . . . . . . . . . . . . . . . 21 wherer . . . . . . . . . . . . . . . . . . . . . . . 22 3. VARIABLES . . . . . . . . . . . . . . . . . . . . . . . 23 System Hardware . . . . . . . . . . . . . . . . . . . 23 Video Hardware . . . . . . . . . . . . . . . . . . . 24 Video Software . . . . . . . . . . . . . . . . . . . 26 Video Cursor . . . . . . . . . . . . . . . . . . . . 28 2 QWIKC Screen Utilities Reference Guide, Version 2.1 1. I N T R O D U C T I O N PURPOSE This document is a QWIKC technical reference manual describing each routine and variable in detail in a format similar to the Turbo C manual. The routines are described in alphabetical order. Since this manual is on disk, you can find your interest easily with a search utility. Application - All QWIKC functions will perform in the following applications: . All video text modes - 0, 1, 2, 3 and 7. . Any column mode - 40, 80, or variable. . For IBM PC, XT, AT, PCjr, PC convertible, all PS/2 models, 3270 PC, and compatibles. . With MDA, CGA, EGA, MCGA, VGA, 8214/A, all Hercules video cards. . Perform routines in absolute coordinates rather than window-relative coordinates. . Capitalizes on the use of faster multi-tasking video buffers (MTVB). For window-relative writing routines, see WNDWC21.ARC. COMMON PARAMETERS Common Parameters - Most functions use the same parameter names. Rather than repeating them for each routine, detailed descriptions for those parameters are listed below. Screen Coordinates - QWIKC routines work in absolute coordinates to give you full control of the screen. The routines do not check for bounds on the screen, so be sure to stay in range. The upper left column on the screen is row 1, column 1, which is also called 1-based. The routines also wrap to the next line; they do not truncate at end-of-line. For example, row=1 and col=255 is equivalent to row=3 and col=15 on a screen with 80 columns. But this is not a recommended practice for variable screen widths. row/col - row and col were chosen in lieu of the X/Y scheme used in most routines. Since QWIKC is for only text modes, the screen is treated like a word processor with rows and columns. It is more intuitive to use the X/Y scheme in graphics and the row/col scheme for text. coll/colr - In the self-centering routines, the left and right columns are simply averaged. To center on the full width of an 80 column display, set coll=1 and colr=80. To center on a certain column number, set both values equal to that column number. Or, to center on any screen, set coll=1 and colr=crt_cols. rows/cols - Using rows/cols is much easier than row2/col2 to describe the height and width of a block such as: qstoretomem( row, col, rows, cols, myptr ); 3 QWIKC Screen Utilities Reference Guide, Version 2.1 Should you decide to move a block, only row and col need to be changed, and therefore rows and cols don't need to be mentally recalculated and altered. Please keep cols no greater than crt_cols. Zero values will simply exit the routine. astr - This parameter contains the address of the string. ATTRIBUTES attr - Use the convenient attribute macros for the foreground and background colors supplied in the header file, for example: qwrite( 1, 1, WHITE+BLUE_BG, "My String" ); will write the text with white on blue attributes. The foreground macros in QWIKC21.H are duplicates of those in Turbo C's conio.h: BLACK 0x00 DARKGRAY 0x08 BLUE 0x01 LIGHTBLUE 0x09 GREEN 0x02 LIGHTGREEN 0x0A CYAN 0x03 LIGHTCYAN 0x0B RED 0x04 LIGHTRED 0x0C MAGENTA 0x05 LIGHTMAGENTA 0x0D BROWN 0x06 YELLOW 0x0E LIGHTGRAY 0x07 WHITE 0x0F BLINK 0x80 For convenience, background color macros were included so that the foreground and background macros could be added for the complete attribute. BLACK_BG 0x00 BLUE_BG 0x10 GREEN_BG 0x20 CYAN_BG 0x30 RED_BG 0x40 MAGENTA_BG 0x50 BROWN_BG 0x60 LIGHTGRAY_BG 0x70 SAMEATTR -1 SAMEATTR - A powerful and unique feature of all QWIKC routines is the use of the macro SAMEATTR. If SAMEATTR, or a negative value, is used as an attribute, the routine will suppress any changes to the attributes and use what is currently on the screen. 3270 PC Attributes - Be aware that the 3270 PC ignores the foreground intensity bit, so there are only 8 colors. In addition, 4 colors have different tints: 4 QWIKC Screen Utilities Reference Guide, Version 2.1 PC Color 3270 PC Color ------------ ------------- Cyan Turquoise Magenta Pink Brown Yellow Light Gray White 5 QWIKC Screen Utilities Reference Guide, Version 2.1 2. F U N C T I O N S In this section, a detailed description is provided for each function. --------------------------------------------------------------------------- eosc QWIKC --------------------------------------------------------------------------- Function Returns the absolute column of the EOS marker. Syntax unsigned char eosc(void); Remarks Operates on the currently written screen. The upper left corner of the screen (1,1). Return value eosc returns the absolute column of the EOS marker. Screens All video pages and virtual screens. See also eosr, eostorc, eostorcrel, eostocursor, eosln, gotoeos --------------------------------------------------------------------------- eosln QWIKC --------------------------------------------------------------------------- Function Moves the EOS marker to column 1 of the next row. Syntax void eosln(void); Remarks Operates on the currently written screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions eosln can increment past the last row of a screen, but does not scroll up the screen. See also eosr, eosc, eostorc, eostorcrel, eostocursor, gotoeos, qeosln --------------------------------------------------------------------------- eosr QWIKC --------------------------------------------------------------------------- Function Returns the absolute row of the EOS marker. Syntax unsigned char eosr(void); Remarks Operates on the currently written screen. Return value eosr returns the absolute row of the EOS marker. Screens All video pages and virtual screens. See also eosc, eostorc, eostorcrel, eostocursor, eosln, gotoeos --------------------------------------------------------------------------- eostocursor QWIKC --------------------------------------------------------------------------- Function Positions the EOS marker to where the cursor is. Syntax void eostocursor(void); Remarks The EOS marker is simply moved to match the position of the cursor of the currently written video page. Return value None. Screens All video pages only. EOS Updated. See also eosr, eosc, eostorc, eostorcrel, eosln, gotoeos 6 QWIKC Screen Utilities Reference Guide, Version 2.1 --------------------------------------------------------------------------- eostorc QWIKC --------------------------------------------------------------------------- Function Positions the EOS marker. Syntax void eostorc( unsigned char row, unsigned char col ); Remarks Use this procedure to manually locate the EOS marker. The q*eos functions will write where this marker is located on the currently written screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also eosr, eosc, eostorcrel, eostocursor, eosln, gotoeos --------------------------------------------------------------------------- eostorcrel QWIKC --------------------------------------------------------------------------- Function Positions the EOS marker relative to its current position. Syntax void eostorcrel( unsigned char row, unsigned char col ); Remarks The relative values can be positive or negative. The q*eos functions will write where the EOS marker is located on the currently written screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also eosr, eosc, eostorc, eostocursor, eosln, gotoeos --------------------------------------------------------------------------- getcursor QWIKC --------------------------------------------------------------------------- Function Returns the cursor mode for the CRT. Syntax int getcursor(void); Remarks There is only one cursor mode variable that applies to what is currently viewed on the CRT and it is retrieved from low memory at 0040h:0060h. Return value getcursor returns the cursor mode for the CRT. Screens All video pages only. See also setcursor, modcursor --------------------------------------------------------------------------- get_submodel_id QWIKC --------------------------------------------------------------------------- Function Gets the submodel_id on IBM computers. Syntax void get_submodel_id(void); Remarks The system_id and submodel_id variables are updated if a submodel ID exists. It will only execute on recent models of XT, AT, and PS/2 models which have this ID. Otherwise the variables will remain unaltered as set by qinit(). Return value None. The result of the submodel ID check is stored in submodel_id. Restrictions PC or XT clones must recognize IBM's system ID. See also QWIKC21.DOC 7 QWIKC Screen Utilities Reference Guide, Version 2.1 --------------------------------------------------------------------------- gotoeos QWIKC --------------------------------------------------------------------------- Function Positions the cursor where the EOS marker is. Syntax void gotoeos(void); Remarks The cursor is simply moved to match the position of the EOS marker of the currently written video page. Return value None. Screens All video pages only. EOS Unaltered. See also eosr, eosc, eostorc, eostorcrel, eostocursor, eosln, gotorc Example Center a string on the screen and place the cursor at the end of the string: qwritec( 1, 1, crt_cols, SAMEATTR, "My message " ); gotoeos(); --------------------------------------------------------------------------- gotorc QWIKC --------------------------------------------------------------------------- Function Positions the cursor. Syntax void gotorc( unsigned char row, unsigned char col ); Remarks The cursor is moved to the position absolute to the currently written video page. Return value None. Screens All video pages only. EOS Unaltered. Restrictions Stay within the screen limits. See also gotoeos, wherer, wherec --------------------------------------------------------------------------- modcursor QWIKC --------------------------------------------------------------------------- Function Modifies the current cursor mode to turn on, off, or blink erratically. Syntax void modcursor( int bits13and14 ); Remarks Using the modification macros cursor_on, cursor_off, or cursor_blink for bits13and14, the currently viewed cursor mode on the CRT will be modified accordingly. The function only looks at bits 13 and 14 of bits13and14 for the modification. The scan lines remain unaltered. Return value None. Screens Any video page as viewed. See also getcursor, setcursor Example To turn the current cursor mode off: modcursor( cursor_off ); 8 QWIKC Screen Utilities Reference Guide, Version 2.1 --------------------------------------------------------------------------- qattr QWIKC --------------------------------------------------------------------------- Function Changes just the attribute in a rows-by-columns block on the screen. Syntax void qattr( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, int attr ); Remarks The upper left corner of the block starts at (row,col) and the block size is rows by cols. Note that you can even change 1 row and/or 1 column. If SAMEATTR is used for attr or if rows or cols is zero, then nothing is written. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qattrc, qattreos Example To create inverse video on any screen: qattr( 1, 1, crt_rows, crt_cols, BLACK+LIGHTGRAY_BG ); --------------------------------------------------------------------------- qattrc QWIKC --------------------------------------------------------------------------- Function Changes just the attribute in a rows-by-columns block on the screen and centers it between two columns. Syntax void qattrc( unsigned char row, unsigned char coll, unsigned char colr, unsigned char rows, unsigned char cols, int attr ); Remarks The upper left corner of the block starts at (row,(coll+colr-cols+1) >> 1) with a block size of rows by cols and centering it between the two columns coll and colr. Odd counts are shifted left. If SAMEATTR is used for attr or if rows or cols is zero, then nothing is written. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qattr, qattreos Example A 30 character message centered on the screen in row 15, needs to be white on green: qattrc( 15, 1, crt_cols, 1, 30, WHITE+GREEN_BG ); The attribute will start to be changed in column 26 on an 80 column screen. --------------------------------------------------------------------------- qattreos QWIKC --------------------------------------------------------------------------- Function Changes just the attribute in a rows-by-columns block on the current screen starting at the EOS marker. Syntax void qattreos( unsigned char rows, unsigned char cols, int attr ); Remarks The upper left corner of the block starts at the previously 9 QWIKC Screen Utilities Reference Guide, Version 2.1 set EOS marker and the block size is rows by cols. If SAMEATTR is used for attr or if rows or cols is zero, then nothing is written. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qattr, qattrc Example To highlight a 20 column data entry field at the EOS marker with yellow on magenta: qattreos( 1, 20, YELLOW+MAGENTA_BG ); --------------------------------------------------------------------------- qeosln QWIKC --------------------------------------------------------------------------- Function Moves the EOS marker to column 1 of the next row with a possible scroll up. Syntax void qeosln(void); Remarks Operates on the currently written screen. If eosr becomes greater than crt_rows, then the screen will scroll up. The new blank row will have the attribute set by scroll_attr which must be manually set before hand. scroll_attr is defined in QWIKC21.H. Return value None. Screens All video pages and virtual screens. EOS Updated to first cleared column of the cleared row. See also eosr, eosc, eostorc, eostorcrel, eostocursor, gotoeos, eosln --------------------------------------------------------------------------- qfill QWIKC --------------------------------------------------------------------------- Function Fills the screen with a character with an optional attribute change in a rows-by-columns block on the current screen. Syntax void qfill( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, int attr, unsigned char ch ); Remarks The upper left corner of the block starts at (row,col) and the block size is rows by cols. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. If rows or cols is zero, then nothing is written. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qfillc, qfilleos Example To clear the screen with black on brown attribute: qfill( 1, 1, crt_rows, crt_cols, BLACK+BROWN_BG, ' ' ); --------------------------------------------------------------------------- qfillc QWIKC --------------------------------------------------------------------------- Function Fills the screen with a character and an optional attribute change in a rows-by-columns block on the current screen and 10 QWIKC Screen Utilities Reference Guide, Version 2.1 centers it between two columns. Syntax void qfillc( unsigned char row, unsigned char coll, unsigned char colr, unsigned char rows, unsigned char cols, int attr, unsigned char ch ); Remarks The upper left corner of the block starts at (row,(coll+colr-cols+1) >> 1) with a block size of rows by cols and centered between the two columns coll and colr. Odd counts are shifted left. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. If rows or cols is zero, then nothing is written. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qfill, qfilleos Example Center 20 dashes on the screen in rows 1 to 5 with black on brown attributes: qfillc( 1, 1, crt_cols, 5, 20, BLACK+BROWN_BG, '-' ); --------------------------------------------------------------------------- qfilleos QWIKC --------------------------------------------------------------------------- Function Fills the screen with a character with an optional attribute change in a rows-by-columns block on the current screen starting at the EOS marker. Syntax void qfilleos( unsigned char rows, unsigned char cols, int attr, unsigned char ch ); Remarks The upper left corner of the block starts at the previously set EOS marker and the block size is rows by cols. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. If rows or cols is zero, then nothing is written. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qfill, qfillc Example To clear a 20 column data entry field at the EOS marker with yellow on magenta: qfilleos( 1, 20, YELLOW+MAGENTA_BG, ' ' ); --------------------------------------------------------------------------- qinit QWIKC --------------------------------------------------------------------------- Function Detects system, display, and video card(s). Initializes global data for QWIKC routines. Syntax void qinit(void); Remarks qinit() must be called at the start of your program to initialize QWIKC. qreinit() should be called if there is a text mode change. Return value None. QWIKC's global variables are set to match the video configuration of your system. 11 QWIKC Screen Utilities Reference Guide, Version 2.1 EOS Set to (1,1). See also qreinit(), QWIKC21.DOC, QINITEST.C, VARIABLES section below. --------------------------------------------------------------------------- qreadattr QWIKC --------------------------------------------------------------------------- Function Reads an attribute from the current screen. Syntax unsigned char qreadattr( unsigned char row, unsigned char col ); Remarks Reads an attribute from the screen at just one location. Return value qreadattr returns the attribute read from the screen. Screens All video pages and virtual screens. EOS Unaltered. See also qreadchar, qreadstr --------------------------------------------------------------------------- qreadchar QWIKC --------------------------------------------------------------------------- Function Reads a character from the current screen. Syntax unsigned char qreadchar( unsigned char row, unsigned char col ); Remarks Reads a character from the screen at just one location. Return value qreadchar returns the character read from the screen. Screens All video pages and virtual screens. EOS Unaltered. See also qreadattr, qreadstr --------------------------------------------------------------------------- qreadstr QWIKC --------------------------------------------------------------------------- Function Reads a text string from the current screen. Syntax void qreadstr( char far *astr, unsigned char row, unsigned char col, unsigned char cols ); Remarks Reads a string of characters from the screen, storing it in the location pointed to by astr. Return value None. Screens All video pages and virtual screens. EOS Unaltered. See also qreadattr, qreadchar --------------------------------------------------------------------------- qreinit QWIKC --------------------------------------------------------------------------- Function Detects system, display, and video card(s). Reinitializes global data for QWIKC routines. Syntax void qreinit(void); Remarks qreinit() must be called after changing text modes to re- initialize QWIKC. qinit() must be called at the start of your program. Return value None. QWIKC's global variables are reset to match the new text mode and video configuration of your system. EOS Set to (1,1). See also qinit(), QWIKC21.DOC, QINITEST.C, VARIABLES section below. 12 QWIKC Screen Utilities Reference Guide, Version 2.1 --------------------------------------------------------------------------- qscrolldown QWIKC --------------------------------------------------------------------------- Function Scrolls a rows-by-columns block down on the current screen and clears the top row of the block. Syntax void qscrolldown( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, int blankattr ); Remarks To keep it simple, the block encompasses all affected rows including the row to be cleared. The upper left corner of the block starts at (row,col) and the block size is rows by cols. The bottom row will be scrolled out and lost while the top row will be cleared with the attribute of blankattr (SAMEATTR is permitted). Note that you can even change 1 row and/or 1 column. The cursor is not moved, but is ready to be moved with gotoeos. The cpuid lets the routine choose the best speed. Return value None. Screens All video pages and virtual screens. EOS Updated to first cleared column of the cleared row. Restrictions Stay within the screen limits. See also qscrollup, gotoeos Example To scroll down the entire screen and clear the top row with light cyan on blue: qscrolldown( 1,1, crt_rows, crt_cols, LIGHTCYAN+BLUE_BG ); --------------------------------------------------------------------------- qscrollup QWIKC --------------------------------------------------------------------------- Function Scrolls a rows-by-columns block up on the current screen and clears the bottom row of the block. Syntax void qscrollup( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, int blankattr ); Remarks To keep it simple, the block encompasses all affected rows including the row to be cleared. The upper left corner of the block starts at (row,col) and the block size is rows by cols. The first row will be scrolled out and lost while the last row will be cleared with the attribute of blankattr (SAMEATTR is permitted). Note that you can even change 1 row and/or 1 column. The cursor is not moved, but is ready to be moved with gotoeos. The cpuid lets the routine choose the best speed. Return value None. Screens All video pages and virtual screens. EOS Updated to first cleared column of the cleared row. Restrictions Stay within the screen limits. See also qscrolldown, gotoeos Example To scroll up the entire screen and clear the last row with light cyan on blue: qscrollup( 1, 1, crt_rows, crt_cols, LIGHTCYAN+BLUE_BG ); 13 QWIKC Screen Utilities Reference Guide, Version 2.1 --------------------------------------------------------------------------- qscrtovscr QWIKC --------------------------------------------------------------------------- Function Copies a rows-by-columns block on the current screen to another location on a virtual screen. Syntax void qscrtovscr( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, unsigned char vrow, unsigned char vcol, unsigned char vwidth, void far *vscrptr ); Remarks row, col, rows, and cols locates the block on the current screen (scr) as specified by qscr. This block will be copied to the virtual screen (vscr) at the location of vrow and vcol. But since vscr may have a different column width than scr, vwidth sets the width. vscrptr is the base ad- dress of the virtual screen. By changing qscr, you can even copy blocks from one virtual screen to another! Only the scr side checks for possible snow. Return value None. Screens All video pages and virtual screens. EOS Unaltered. Restrictions Stay within the screen limits. Not intended for copying between video pages (esp. CGA). See also qvscrtoscr Example Copy a 12x40 block from the CRT screen at (5,10) to a virtual screen at (3,2) and look at the result on the CRT: #include <stdio.h> #include <conio.h> #include "qwikc21.h" #define vscrrows 20 #define vscrcols 60 /* Storage size in bytes required is: rows * cols << 1 */ int vscr[vscrrows][vscrcols]; /* 20 x 60 virtual screen */ vscr_t crt,myvscr; main() { qinit(); /* create specs for virtual screen */ myvscr.vrows=vscrrows; myvscr.vcols=vscrcols; myvscr.vsize=sizeof(vscr); myvscr.vsnow=0; /* qwikest when 0 */ myvscr.veosofs=0; myvscr.vscrptr=𝓋 qfill( 1, 1, crt_rows, crt_cols, WHITE+BLUE_BG, '*' ); /* Fill CRT */ crt=qscr; /* Save CRT specs */ qscr=myvscr; /* Set virtual specs */ qfill(1, 1, vscrrows, vscrcols, BLACK+BROWN_BG, '?'); /* Fill vscr */ qscr=crt; /* Restore CRT specs */ qscrtovscr( 5, 10, 12, 40, 3, 2, vscrcols, vscr ); /* Copy block */ qstoretoscr( 1, 1, vscrrows, vscrcols, vscr ); /* Take a look */ 14 QWIKC Screen Utilities Reference Guide, Version 2.1 getch(); return; } --------------------------------------------------------------------------- qstoretomem QWIKC --------------------------------------------------------------------------- Function Saves a rows-by-columns block from the current screen to memory. Syntax void qstoretomem( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, void far *dest ); Remarks row, col, rows, and cols locates the block on the current screen as specified by qscr. This block will be copied to dest, the destination, as one contiguous array. By changing qscr, you can even save blocks from virtual screens! Be sure to set qsnow to false for the fastest speed on virtual screens. Return value None. Screens All video pages and virtual screens. EOS Unaltered. Restrictions Stay within the screen limits. Not intended for copying between video pages (esp. CGA). See also qstoretoscr Example Save a 12x40 block from the CRT screen at (5,10), clear the screen, and restore the block: #include <stdio.h> #include <conio.h> #include "qwikc21.h" #define memrows 12 #define memcols 40 /* Storage size in bytes required is: rows * cols >> 1 */ int block[memrows][memcols]; /* 12 x 40 block */ main() { qinit(); qfill( 1, 1, crt_rows, crt_cols, WHITE+BLUE_BG, '*'); /* Fill CRT */ qstoretomem( 5, 10, memrows, memcols, block ); /* Save block */ qfill(1,1, crt_rows, crt_cols, YELLOW+BLACK_BG,' '); /* Clear CRT */ qstoretoscr( 5, 10, memrows, memcols, block ); /* Take a look */ getch(); return; } --------------------------------------------------------------------------- qstoretoscr QWIKC --------------------------------------------------------------------------- Function Writes a rows-by-columns block to the current screen from memory. Syntax void qstoretoscr( unsigned char row, unsigned char col, 15 QWIKC Screen Utilities Reference Guide, Version 2.1 unsigned char rows, unsigned char cols, void far *source ); Remarks row and col locates the upper left corner of the block on the current screen as specified by qscr. A block will be written from source, which is one contiguous array, and placed on the screen as a rows-by-cols block. By changing qscr, you can even place blocks to virtual screens! Be sure to set qsnow to 0 for the fastest speed on virtual screens. Return value None. Screens All video pages and virtual screens. EOS Unaltered. Restrictions Stay within the screen limits. Not intended for copying between video pages (esp. CGA). See also qstoretomem Example Save a 12x40 block from the CRT screen at (5,10) in the heap, clear the screen, and restore the block: #include <stdio.h> #include <conio.h> #include <stdlib.h> #include "qwikc21.h" #define memrows 12 #define memcols 40 /* Storage size in bytes required is: rows * cols << 1 */ int *block; main() { qinit(); qfill( 1, 1, crt_rows, crt_cols, WHITE+BLUE_BG, '*' ); /* Fill CRT */ block=malloc(memrows * memcols << 1); /* Reserve heap */ qstoretomem( 5, 10, memrows, memcols, block ); /* Save Block */ qfill(1,1, crt_rows, crt_cols, YELLOW+BLACK_BG, ' '); /* Clear CRT */ qstoretoscr( 5, 10, memrows, memcols, block ); /* Take a look */ free(block); /* Free heap */ getch(); return; } --------------------------------------------------------------------------- qviewpage QWIKC --------------------------------------------------------------------------- Function Changes the video page to be viewed on the CRT. Syntax void qviewpage( char pagenum ); Remarks Standard C routines are dedicated only to video page 0. However, most video cards, except MDA and some 3270 PC, have more than one video page. This procedure enables you to view those pages. The number of video pages available is detected by qinit and saved in maxpage. pagenum is 0-based and the routine will only view other pages when pagenum <= maxpage. The macro videopage is used to get/set the currently viewed page. Return value None. Screens All video pages. 16 QWIKC Screen Utilities Reference Guide, Version 2.1 EOS Unaltered. See also qwritepage, QWIKC21D.DOC, QINITEST.C --------------------------------------------------------------------------- qvscrtoscr QWIKC --------------------------------------------------------------------------- Function Copies a rows-by-columns block from a virtual screen to another location on the current screen. Syntax void qvscrtoscr( unsigned char row, unsigned char col, unsigned char rows, unsigned char cols, unsigned char vrow, unsigned char vcol, unsigned char vwidth, void far *vscrptr ); Remarks row, col, rows, and cols locates the destination on the current screen (scr) as specified by qscr. A block will be copied from the virtual screen (vscr) at the location of vrow and vcol. But since vscr may have a different column width than scr, vwidth sets the width. vscrptr is the base address of the virtual screen. By changing qscr, you can even copy blocks from one virtual screen to another! Only the scr side checks for possible snow. Return value None. Screens All video pages and virtual screens. EOS Unaltered. Restrictions Stay within the screen limits. Not intended for copying between video pages (esp. CGA). See also qscrtovscr Example Copy a 12x40 block from the CRT screen at (5,10) to a virtual screen at (3,2) and look at the result on the CRT: #include <stdio.h> #include <conio.h> #include "qwikc21.h" #define vscrrows 20 #define vscrcols 60 /* Storage size in bytes required is: rows * cols << 1 */ int vscr[vscrrows][vscrcols]; /* 20 x 60 virtual screen */ vscr_t crt,myvscr; main() { qinit(); /* create specs for virtual screen */ myvscr.vrows=vscrrows; myvscr.vcols=vscrcols; myvscr.vsize=sizeof(vscr); myvscr.vsnow=0; /* qwikest when 0 */ myvscr.veosofs=0; myvscr.vscrptr=𝓋 qfill( 1, 1, crt_rows, crt_cols, WHITE+BLUE_BG, '*' ); /* Fill CRT */ crt=qscr; /* Save CRT specs */ qscr=myvscr; /* Set virtual specs */ qfill(1, 1, vscrrows, vscrcols, BLACK+BROWN_BG, '?'); /* Fill vscr */ 17 QWIKC Screen Utilities Reference Guide, Version 2.1 qscr=crt; /* Restore CRT specs */ qscrtovscr( 5, 10, 12, 40, 3, 2, vscrcols, vscr ); /* Copy Block */ qstoretoscr( 1, 1, vscrrows, vscrcols, vscr ); /* Take a look */ getch(); return; } --------------------------------------------------------------------------- qwrite QWIKC --------------------------------------------------------------------------- Function Writes a string to the current screen with an optional attribute change. Syntax void qwrite( unsigned char row, unsigned char col, int attr, char far *astr ); Remarks This routine writes the string astr at (row,col) with the attribute attr. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qwritec, qwrite_sub, qwriteeos, qwriteeos_sub Example Write the string "Important" at (2,1) with the attribute of flashing white on red: qwrite( 2, 1, BLINK+WHITE+RED_BG, "Important" ); --------------------------------------------------------------------------- qwritec QWIKC --------------------------------------------------------------------------- Function Writes a string to the current screen with an optional attribute change and centered between two columns. Syntax void qwritec( unsigned char row, unsigned char coll, unsigned char colr, int attr, char far *astr ); Remarks This routine writes the string astr at (row,(coll+colr- strlen(astr)+1) >> 1) which centers it between the two columns coll and colr and has the attribute attr. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qwrite, qwrite_sub, qwriteeos, qwriteeos_sub Example Write a message centered on the screen in row 15 with black on green attributes: qwritec( 15, 1, crt_cols, WHITE+GREENBG, "My message" ); The message will be written in column 36 on an 80 column screen. 18 QWIKC Screen Utilities Reference Guide, Version 2.1 --------------------------------------------------------------------------- qwriteeos QWIKC --------------------------------------------------------------------------- Function Writes a string to the current screen with an optional attribute change starting at the EOS marker. Syntax void qwriteeos( int attr, char far *astr ); Remarks This routine writes the string astr at the EOS marker with the attribute attr. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qwrite, qwrite_sub, qwritec, qwriteeos_sub Example Highlight the number in the following message: qwrite( 1, 1, WHITE+BLUE_BG, "There are" ); qwriteeos( YELLOW+BLUE_BG, " 5 " ); qwriteeos( WHITE+BLUE_BG, "minutes left." ); which will write "There are 5 minutes left." as white on blue except "5" will be yellow on blue. --------------------------------------------------------------------------- qwriteeos_sub QWIKC --------------------------------------------------------------------------- Function Writes an array (or string) with a specified length to the current screen with an optional attribute change starting at the EOS marker. Syntax void qwriteeos_sub( int attr, int length, char far *astr ); Remarks This routine writes length characters of the string pointed to by astr at the previously set EOS marker with the attribute attr. This enables you to write substrings when specifying a starting index (astr[i]). (Other routines like qwriteeos stop at the null-terminating character.) Of course, astr can be any char array or char pointer. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qwrite_sub, qwritec, qwriteeos, Example The following code will write "Testing step B" with the existing screen attributes: strcpy( mystr, "Now for step B: Testing out this line." ); qwrite_sub( 1, 5, SAMEATTR, 8, &mystr[16] ); qwriteeos_sub( SAMEATTR, 6, &mystr[8]); --------------------------------------------------------------------------- qwritepage QWIKC --------------------------------------------------------------------------- Function Changes the video page on which the QWIKC routines write. Syntax void qwritepage( char pagenum ); 19 QWIKC Screen Utilities Reference Guide, Version 2.1 Remarks Standard C routines are dedicated to only video page 0. However, most video cards, except MDA and some 3270 PC, have more than one video page. This function enables QWIKC routines to write to those pages by altering qscrofs and qvideo_page which is the current page on which QWIKC is writing. The number of video pages available is detected by qinit() and saved in maxpage. The routine will only change pages when pagenum <= maxpage. Return value None. Screens All video pages. EOS Unaltered. See also qviewpage, QWIKC21.DOC, QINITEST.C --------------------------------------------------------------------------- qwrite_sub QWIKC --------------------------------------------------------------------------- Function Writes an array (or string) with a specified length to the current screen with an optional attribute change. Syntax void qwrite_sub( unsigned char row, unsigned char col, int attr, int length, char far *astr ); Remarks This routine writes length characters of the string astr at (row,col) with the attribute attr. This enables you to write substrings when specifying a starting index (astr[i]). (Other routines like qwrite stop at the null-terminating character.) Of course, astr can be any char array or char pointer. If SAMEATTR is used for attr, then the attribute will remain the same on the screen. Return value None. Screens All video pages and virtual screens. EOS Updated. Restrictions Stay within the screen limits. See also qwrite, qwritec, qwriteeos, qwriteeos_sub Example The following code will write "Testing out this line." with the existing screen attributes: strcpy( mystr, "Step B: Testing out this line." ); qwrite_sub( 1, 1, SAMEATTR, 22, &mystr[9] ); --------------------------------------------------------------------------- setcursor QWIKC --------------------------------------------------------------------------- Function Sets a new cursor mode for the CRT. Syntax void setcursor( int cursor ); Remarks Using the default cursor variables set by qinit and/or the cursor macros, a new cursor mode can be set by with any combination of: cursor_initial - detected by qinit at startup cursor_underline - set by qinit cursor_halfblock - set by qinit cursor_block - set by qinit cursor_off ($2000) - turns cursor off cursor_blink ($6000) - erratic blinking (MDA/CGA) You can simply add them together (logically ORing is best to 20 QWIKC Screen Utilities Reference Guide, Version 2.1 prevent carry errors, but arithmetic addition is fine). Although a separate cursor location is kept for each video page, there is only one cursor mode for the CRT screen. Screens Any video page as viewed. See also getcursor, modcursor Example 1 Set a half-block cursor with erratic blink: setcursor( cursor_halfblock+cursor_blink ); Example 2 Set the scan lines for a block cursor, but leave it turned off: setcursor( cursor_block+cursor_off ); Example 3 Restore the cursor mode at start up and be sure it's turned on: setcursor( cursor_initial ); modcursor( cursor_on ); or, for those comfortable with bit operations: setcursor( cursor_initial & !cursor_blink ); --------------------------------------------------------------------------- setmultitask QWIKC --------------------------------------------------------------------------- Function Set QWIKC variables to write direct to multi-tasking video buffers (MTVB). Syntax void setmultitask(void); Remarks This function alters the following variables if the program is running under a multi-tasking environment and the user has chosen to use the faster MTVB. If there is no multi- tasking environment or the MTVB is not used (normal direct screen video), then these variables are unaltered. If you use Turbo C's conio routines, be sure to set directvideo to 0 when using the MTVB. qscrptr - the segment is altered, but the offset is usually 0. page0seg - set to match qscrseg to indicate page 0. qsnow - set to 0. inmultask - 1 if using MTVB, otherwise set to 0. See also inmultask in VARIABLES section below. --------------------------------------------------------------------------- wherec QWIKC --------------------------------------------------------------------------- Function Returns the absolute column of the cursor on the currently written video page. Syntax unsigned char wherec(void); Remarks Operates on the currently written video page. The upper left corner of the screen (1,1). Return value None. 21 QWIKC Screen Utilities Reference Guide, Version 2.1 Screens All video pages only. See also gotorc, wherer --------------------------------------------------------------------------- wherer QWIKC --------------------------------------------------------------------------- Function Returns the absolute row of the cursor on the currently written video page. Syntax unsigned char wherer(void); Remarks Operates on the currently written video page. The upper left corner of the screen (1,1). Return value None. Screens All video pages only. See also gotorc, wherec --------------------------------------------------------------------------- 22 QWIKC Screen Utilities Reference Guide, Version 2.1 3. V A R I A B L E S The variables in QWIKC are initialized according to the the kind of system, display(s), and video adapter(s) that qinit detects. QWIKC uses them for reference and they may also be used in your own programming to help make decisions. SYSTEM HARDWARE System Hardware Variables - These variables indicate the kind of computer that qinit detected: Variable Description ------------ ----------------------------------------------------------- cpuid (Type: char) Intel CPU identification code. cpuid can be equal to any one of the following four marcos: cpu8086 - Intel 8086/8088 cpu80186 - Intel 80186/80188 cpu80286 - Intel 80286 cpu80386 - Intel 80386 system_id (Type: char) Code for the IBM computer in use, set by qinit. See submodel_id for values. submodel_id (Type: char) Code for the sub-model of the IBM computer in use. This value defaults to 0 the first time qinit is run. To get a value, execute get_submodel_id. SysID Submodel SYSTEM ----- -------- ------------------------------ 0xFF n/a IBM PC 0xFE n/a IBM PC XT 0xFD n/a IBM PCjr 0xFC n/a IBM PC AT (6 MHz, 01/10/84) 0x00 IBM PC AT (6 MHz, 06/10/85) 0x01 IBM PC AT (8 MHz, 11/15/85) 0x02 IBM PC XT (286) 0x04 IBM PS/2 model 50 0x05 IBM PS/2 model 60 0xFB 0x00 IBM PC XT (256/640) 0xFA 0x00 IBM PS/2 model 30 0x01 IBM PS/2 model 25 0xF9 0x00 IBM PC Convertible 0xF8 0x00 IBM PS/2 model 80 (16 MHz) 0x04 IBM PS/2 model 80 (20 MHz) 0x09 IBM PS/2 model 70 (16 MHz) 23 QWIKC Screen Utilities Reference Guide, Version 2.1 VIDEO HARDWARE Video Hardware Variables - These variables indicate the kind of video card(s) and display(s) that qinit detected: Variable Description ------------- --------------------------------------------------- active_disp_dev (Type: char) Code for the Active Display Device. Using IBM's Display Combination Code (DCC), qinit detects the video adapter combined with the video display. The codes have been set to the following macros. Note that monochrome is odd and color is even: Macro Code Description ---------- ----- -------------------------------- no_display 0x00 No display mda_mono 0x01 MDA with 5151 monochrome display cga_color 0x02 CGA with 5153/4 color display dcc3 0x03 reserved ega_color 0x04 EGA with 5153/4 color ega_mono 0x05 EGA with 5151 monochrome pgc_color 0x06 PGC with 5175 color vga_mono 0x07 VGA with analog monochrome vga_color 0x08 VGA with analog color dcc9 0x09 reserved dcc10 0x0A reserved mcga_mono 0x0B MCGA with analog monochrome mcga_color 0x0C MCGA with analog color n/a 0x0D to 0xFE - reserved unknown 0xFF unknown device active_disp_dev_3270 (Type: char) Code for the Active Display Device on the 3270 PC. Only the 0xFF code corresponds to the macro "unknown". Code Monitor Adapter ---- ------------ --------------------- 0x00 5151 or 5272 for 5151 or 5272 0x01 3295 for 3295 0x02 5151 or 5272 for 5151 or 5272 plus XGA graphics 0x03 5279 3270 PC G 0x04 5379 C01 3270 PC GX 0x05 5379 M01 3270 PC GX 0x06 reserved 0x07 reserved 0xFF Unknown, not a 3270 PC alt_disp_dev (Type: char) Code for the Alternate Display Device. This code is detected by qinit for a second (but inactive) adapter and display, just in case there are dual monitors. It uses the same macros as active_disp_dev listed above. 24 QWIKC Screen Utilities Reference Guide, Version 2.1 alt_disp_dev_pcc (Type: int) Code for the Alternate Display adapter on the PC Convertible. In hex, it corresponds to the model number of the attached device: Model Description ------ -------------------- 0x 0 No alternate adapter 0x5140 LCD 0x5153 CGA type 0x5151 Monochrome type cardseg (Type: int) Video segment address of the video "card" as detected by qinit. cardsnow (Type: char) Set to 1 for wait-for-retrace for the video "card" as detected by qinit. egainfo (Type: macro) Returns the value at 0x0040:0x0087 which has the following information when the EGA (or VGA) is present: Bits Description ---- ------------------------------------------- 7 (0) Clear, (1) Keep video data after video mode set 6,5 (00) 64k, (01), 128k, (10) 192k, (11) 256k, memory on the card. 4 Reserved 3 (0) EGA active, (1) EGA not active 2 (0) Disable, (1) Enable wait-for-display 1 (0) CD/ECD (1) MD attached 0 (0) Active, (1) Inactive CD emulation egaswitches (Type: macro) Using the value this macro points to, you can determine the monitor connected to the EGA, the alternate video system, and the start up default. The byte is a copy of how the dip switches are set on the card where on=0 and off=1. The primary is the default. When the ECD is set for 640x200, it is emulating the CD including the cursor mode. qinit directly tests for the alternate device rather than assuming it. Switch Primary Secondary -------- ------------------- ------------------- 0000 = 0 MDA + MD EGA + CD - 40x25 0001 = 1 MDA + MD EGA + CD - 80x25 0010 = 2 MDA + MD EGA + ECD (640x200) 0011 = 3 MDA + MD EGA + ECD (640x350) 0100 = 4 CGA + CD - 40x25 EGA + MD 0101 = 5 CGA + CD - 80x25 EGA + MD 0110 = 6 EGA + CD - 40x25 MDA + MD 0111 = 7 EGA + CD - 80x25 MDA + MD 1000 = 8 EGA + ECD (640x200) MDA + MD 1001 = 9 EGA + ECD (640x350) MDA + MD 25 QWIKC Screen Utilities Reference Guide, Version 2.1 1010 =10 EGA + MD CGA + CD - 40x25 1011 =11 EGA + MD CGA + CD - 80x25 have_3270 (Type: char) If qinit detects 3270 PC equipment or software, this variable is set to 1. In addition, the active_disp_dev is either mda_mono or cga_color. Note that there may or may not be graphics capability in either case; qinit is not meant to detect graphics. See active_disp_dev_3270 for codes. have_ps2 (Type: char) qinit sets have_ps2 to true if the DCC is supported. This means that the program has detected a PS/2 video card whether it is integrated on a model 30, a PS/2 Display Adapter installed on an IBM XT, or the like. It also means that either MCGA or VGA is present, but not necessarily active. To know which, just check the DCC. herc_model (Type: char) Model of the attached Hercules video card. If no card is detected, then herc_model=no_herc. Macro Code Description ------------ ---- --------------------- no_herc 0 No Hercules card hgc_mono 1 HGC hgc_plus 2 HGC Plus herc_incolor 3 Hercules InColor Card maxpage (Type: char) Maximum possible 0-based video page number. See TABLE 1 in QWIKC21.DOC for ranges. VIDEO SOFTWARE Video Software Variables - These variables indicate the current video mode and screen characteristics to which QWIK is writing and what is being viewed on the CRT. There are several pointer macros listed that duplicate some of the global variables, i.e., crtcolumns and crt_cols. It is preferable to use the global ones, where the pointer macros are only needed for handling exceptions. Variable Description ------------ ----------------------------------------------------------- crt_cols (Type: macro) Defined as qscr.vcols (current virtual/actual screen columns). qscr.vcols is initialized by qinit/qreinit to the currently viewed number of CRT columns for any card or video mode. crtcolumns (Type: macro) Defined to directly access the 1-based currently viewed number of CRT columns for any card or video mode. This pseudo-variable may be assigned a value, as well as evaluated. 26 QWIKC Screen Utilities Reference Guide, Version 2.1 crt_rows (Type: macro) Defined as qscr.vrows (current virtual/actual screen rows). qscr.vrows is initialized by qinit/qreinit to the currently viewed number of CRT rows for any card or video mode. egafontsize (Type: macro) Defined to directly access the 1-based number of horizontal scan lines per character for EGA/MCGA/VGA. This pseudo-variable may be assigned a value, as well as evaluated. egarows (Type: macro) Defined to directly access the 0-based number of rows on the current screen for EGA, MCGA, and VGA. This number is used to set crt_rows, which is done by qinit. egarows may be assigned a value as well as evaluated. inmultitask (Type: char) This flag indicates if MTVB is being used for the screen in lieu of the normal screen. It defaults to 0 and is possibly altered with setmultitask if the multitasking software has be instructed to expect writing direct to the MTVB (not direct screen). page0seg (Type: unsigned int) Segment for the base page, page 0. In multitasking environments, change this value to its video display buffer. qscrseg and qscrofs should also be set. qeosofs (Type: macro) Defined as vscr.veosofs, the 0-based offset where q*eos functions will write. qscrseg (Type: macro) Acesses the segment of vscr.vscrptr, the segment for QWIKC writing which is altered when changing pages. qscrseg=page0seg on page 0. qscrofs (Type: unsigned int) Offset for QWIKC writing needed for virtual screens. The usual value is 0 for the video pages. qscrptr Combines qscrseg and qscrofs qscr (Type: vscr_t) Structure containing essential variables for QWIKC screen writing. This structure has several macros that access its members: Macro qscr member -------- ----------- crt_rows vrows crt_cols vcols crt_size vsize qsnow vsnow qeosofs veosofs qscrptr vscrptr These macros are also described in this section. Since they are part of a structure, qscr's members can be swapped easily when writing to virtual screens. See the example under qvscrtoscr. 27 QWIKC Screen Utilities Reference Guide, Version 2.1 qsnow (Type: macro) Set to 1 for wait-for-retrace (snow) while QWIKC is writing. qvideo_page (Type: char) Video page to which QWIKC is writing which is set by qwritepage. It is initially 0. qvideo_mode (Type: char) Video mode detected by qinit. scroll_attr (Type: int) The attribute used to clear the blank row when qeosln is used. videomode (Type: macro) Defined to directly access the current video mode in low memory. This pseudo-variable may be assigned a value, as well as evaluated. videopage (Type: macro) Defined to directly access the currently viewed video page in low memory. This pseudo-variable may be assigned a value, as well as evaluated. vscr_t The typedef for the structure of essential variables for QWIKC screen writing to virtual screens. This enables an easy exchange of data between the CRT and virtual screens. VIDEO CURSOR Video Cursor Variables and Macros - These variables and constants give you easy tools to combine with bit operations to display your choice of cursor modes. The variables default with the cursor on and no skew which are detected and set by qinit at startup: Variable Description ----------------- -------------------------------------------------------- cursor_block (Type: unsigned int) Cursor mode value for the full cell. cursor_half_block (Type: unsigned int) Cursor mode value for a half block usually used for insert editing. cursor_initial (Type: unsigned int) Cursor mode value detected at startup. cursor_underline (Type: unsigned int) Cursor mode value for the normal underline. Macro Value Description ------------ ------ --------------------------------------------------- cursor_blink 0x6000 Used to alter bits 13/14 to create erratic blinking on MDA/CGA cards. (EGA/VGA cards turn the cursor off.) cursor_off 0x2000 Used to alter bits 13/14 or can be used by itself to turn the cursor off. 28 QWIKC Screen Utilities Reference Guide, Version 2.1 cursor_on 0x0000 Used to alter bits 13/14 in modcursor to turn the cursor back on. 29