7526 DCT Reference

Reference&mdash.LCD Displays

VioClear

This function clears the video display and sets the cursor position to the upper-left corner of the display.

C Format

     #include   "cfrapi26.h"          // For defined values
 
     USHORT     VioClear()
 
     Returns:   E_OK                  // If no error occurred

Masm Format

      Input:    ah = 0
 
      Call:     INT 44h
 
      Returns:  ax = 0      If no error occurred (only value returned)

Example

int far main (int funct,char far *params)

{

·
// Clear the display
if (VioClear () == E_OK)

// Display cleared
·

else

// Handle error
·


}

VioGetCurPos

This function returns the current row and column position of the cursor.

C Format

     #include   "cfrapi26.h"          // For defined values
 
     USHORT     VioGetCurPos(row, col)
 
     UCHAR      *row                  // Pointer to returned row
     UCHAR      *col                  // Pointer to returned column
 
     Returns:   E_OK                  // If no error occurred
                                      //  (only value returned)

Masm Format

      Input:    ah = 1
 
      Call:     INT 44h
 
      Returns:  dh = row
                dl = col
                ax = 0      If no error occurred (only value returned)

Comments:

Row position range:

Model 100 = 0
Model 200 = 0-1

Column position range:

Model 100 = 0-15
Model 200 = 0-39

Example

int far main (int funct,char far *params)

{

UCHAR row;                  // Returned row
UCHAR col;                  // Returned column
·
// Get the current cursor position
if (VioGetCurPos (&row, &col) == E_OK)

// row and col contain current cursor position
·

else

// Handle error
·


}

VioQuery

This function returns the number of rows and columns and the current display configuration, cursor type, video mode, and character set.

C Format

     #include   "cfrapi26.h"          // For defined values
 
     USHORT     VioQuery(row, col, curtype, mode, charset)
 
     UCHAR      *row                  // Pointer to number of rows
     UCHAR      *col                  // Pointer to number of columns
     UCHAR      *curtype              // Pointer to cursor type
     UCHAR      *mode                 // Pointer to video mode
     UCHAR      *charset              // Pointer to character set
 
     Returns:   E_OK                  // If no error occurred
                                      //  (only value returned)

Masm Format

      Input:    ah = 2
 
      Call:     INT 44h
 
      Returns:  dh = row
                dl = col
                ch = curtype
                bl = mode
                bh = charset = 0
                ax = 0      If no error occurred (only value returned)

Comments:

Defined values returned for video mode are:

00h = TWO_LINE_DISPLAY
01h = ONE_LINE_DISPLAY

Row position range:

Model 100 = 0
Model 200 = 0-1

Column position range:

Model 100 = 0-15
Model 200 = 0-39

Cursor type:

00h = CURSOR_OFF
01h = CURSOR_UNDERBAR
02h = CURSOR_UNDERBAR_BLINK_BLOCK
03h = CURSOR_BLINK_BLOCK

Character type:

Charset always = 0

Example

int far main (int funct,char far *params)

{

UCHAR row;                  //  Number of rows
UCHAR col;                  //  Number of columns
UCHAR curtype;              //  Cursor type
UCHAR mode;                 //  Video mode
UCHAR charset;              //  Character set
·
// Get the display configuration
if (VioQuery (&row, &col,&curtype, &mode, &charset) == E_OK)

// Configuration retrieved
·

else

// Handle error
·


}

VioReadCharStr

This function reads a character string from the display at a specified row and column position.

C Format

     #include   "cfrapi26.h"          // For defined values
 
     USHORT     VioReadCharStr(strpntr, length, row, col,
                                               xfrcnt, curmove)
 
     UCHAR      *strpntr             // Pointer to string data area
     USHORT     length               // Length of character string
     UCHAR      row                  // Row position of string
     UCHAR      col                  // Column position of string
     USHORT     *xfrcnt              // Pointer to count of characters read
     UCHAR      curmove              // Cursor movement flag
 
     Returns:   E_OK                 // If no error occurred
                E_PARAM              // If parameter values are incorrect
                E_END_OF_SCREEN      // If attempt to move past
                                     //  end of screen.

Masm Format

      Input:    ah    =  3
                es:bx = strpntr
                cx    = length
                dh    = row
                dl    = col
                al    = curmove
 
      Call:     INT 44h
 
      Returns:  cx = xfrcnt Actual number of characters read
                ax = 0      If no error occurred
                     1      If parameter values are incorrect
                     2      If attempt to move past end of screen

Comments:

The curmove parameter determines where the cursor will be
placed after the string is read.  If CURSOR_MOVE is
selected, the cursor will be placed at the end of the string.  If
NO_CURSOR_MOVE is selected, the cursor is not moved.  The
curmove parameter does not use the values in the row and column
parameters.
Defined values for CurMove are:

00h    NO_CURSOR_MOVE
01h    CURSOR_MOVE

The row and column parameters determine where the
string will be read on the display.  A value of CUR_ROW (0ffh) for row
will use the current cursor row.  A value of CUR_COL (0ffh)
for column will use the current cursor column.
Row position range:

Model 100 = 0
Model 200 = 0-1

Column position range:

Model 100 = 0-15
Model 200 = 0-39

Example

int far main (int funct,char far *params)

{

UCHAR   string [50];        // String data area
USHORT  length;             // Length of character string
UCHAR   row;                // Row position of string
UCHAR   col;                // Column position of string
USHORT  xfrcnt;             // Count of characters read
UCHAR   curmove;            // Cursor movement flag
·
// Read 10 characters from row 1 column 2
length = 10;
row = 1;
column = 2;
if (VioReadCharStr (string, length, row, column, &xfrcnt,
                                    NO_CURSOR_MOVE) == E_OK)

// String read successfully
·

else

// Handle error
·


}

VioSetCurPos

This function sets the current cursor position at the specified row and column positions.

C Format

     #include   "cfrapi26.h"          // For defined values
 
     USHORT     VioSetCurPos(row, col)
 
     UCHAR      row                   // Row position
     UCHAR      col                   // Column position
 
     Returns:   E_OK                  // If no error occurred
                E_PARAM               // If parameter values are incorrect

Masm Format

      Input:    ah = 4
                dh = row
                dl = col
 
      Call:     INT 44h
 
      Returns:  ax = 0      If no error occurred
                     1      Parameter values are incorrect

Comments:

Row position range:

Model 100 = 0
Model 200 = 0-1

Column position range:

Model 100 = 0-15
Model 200 = 0-39

Example

int far main (int funct,char far *params)

{

UCHAR row;                   // Row position
UCHAR col;                   // Column position
·
// Move the cursor to Row 1, Column 2
row = 1;
col = 2;
if (VioSetCurPos (row, col) == E_OK)

// Cursor positioned as requested
·

else

// Handle error
·


}

VioSetCurType

This function sets the cursor type. This function requires V2.00 microcode or later.

C Format

     #include   "cfrapi26.h"              // For defined values
 
     USHORT     VioSetCurType(type)
 
     UCHAR      type                      // Cursor type
 
     Returns:   E_OK                      // If no error occurred
                E_PARAM                   // If parameter values are incorrect

Masm Format

      Input:    ah = 6
                al = type
 
      Call:     INT 44h
 
      Returns:  ax = 0      If no error occurred
                     1      Parameter values are incorrect

Comments:

Cursor type:

00h = CURSOR_OFF
01h = CURSOR_UNDERBAR
02h = CURSOR_UNDERBAR_BLINK_BLOCK
03h = CURSOR_BLINK_BLOCK

Example

int far main (int funct,char far *params)

{

UCHAR type;                  // Cursor type
·
// Select a blinking block cursor
type = CURSOR_BLINK_BLOCK
if (VioSetCurType (type) == E_OK)

// Cursor type set to big cursor block
·

else

// Handle error
·


}

VioWrtCharStr

This function writes a character-only string to the display at a specified cursor position.

C Format

     #include   "cfrapi26.h"       // For defined values
 
     USHORT     VioWrtCharStr(strpntr, length, row, col,
                                                 xfrcnt, curmove)
 
     UCHAR      *strpntr           // Pointer to character string
     USHORT     length             // Length of string to write
     UCHAR      row                // Row position of string
     UCHAR      col                // Column position of string
     USHORT     *xfrcnt            // Pointer to number of characters written
     UCHAR      curmove            // Cursor movement flag
 
     Returns:   E_OK               // If no error occurred
                E_PARAM            // If parameter values are incorrect
                E_END_OF_SCREEN    // If attempt to move past
                                   //  end of screen.

Masm Format

      Input:    ah    = 5
                es:bx = strpntr
                cx    = length
                dh    = row
                dl    = col
                al    = curmove
 
      Call:     INT 44h
 
      Returns:  cx = xfrcnt Number of characters written
                ax = 0      If no error occurred
                     1      If parameter values are incorrect
                     2      If attempt to move past end of screen

Comments:

The curmove parameter determines where the cursor will be
placed after the string is written.  If CURSOR_MOVE  is
selected, the cursor will be placed at the end of the string.  If
NO_CURSOR_MOVE is selected, the cursor is not moved.  The
curmove parameter does not use the values in the row and column
parameters.
Defined values for curmove are:

00h    NO_CURSOR_MOVE
01h    CURSOR_MOVE

The row and column parameters determine where the
string will be written.  A value of CUR_ROW (0ffh) for row
will use the current cursor row.  A value of CUR_COL (0ffh)
for column will use the current cursor column.
Note that the row and column values are based from 0.
Row position range:

Model 100 = 0
Model 200 = 0-1

Column position range:

Model 100 = 0-15
Model 200 = 0-39

Example

int far main (int funct,char far *params)

{

UCHAR   string [50];        // Character string
USHORT  length;             // Length of string to write
UCHAR   row;                // Row position of string
UCHAR   col;                // Column position of string
USHORT  xfrcnt;             // Number of characters written
UCHAR   curmove;            // Cursor movement flag
·
// Write 10 characters to Row 1, Column 1
length = 10;
row = 1;
col = 1;
if (VioWrtCharStr (string, length, row, column, &xfrcnt,
                                    NO_CURSOR_MOVE) == E_OK)

// String written
·

else

// Handle error
·


}