7526 DCT Reference

Reference&mdash.Keypad

reference&mdash.keypad

KbdReadAscii

This function returns the next make code in the keypad buffer in ASCII form along with the optional File a translation of this character (see Chapter 8. "RAM Files" for details concerning File a).

The USHORT value returned by this function contains the base ASCII character in the low order byte and the File a translation character in the high order byte. The base ASCII character returned in the low byte is always the same, no matter how the keypad has been re-mapped using file a. This allows the CFR to work with physical keys. The upper byte allows the logical mapping of these keys to application or national-language specific printable characters. If File a is not loaded, the ASCII character is duplicated in the high order byte of the returned value. The special keypad keys Enter, Fill, Space and Clear cannot be redefined in File a and are returned with the high order byte set to 0. The ASCII codes for these four special keys are defined in the CFRAPI26.H include file.

On the 7526 Model 200, when the Shift key is used in conjunction with the base ASCII characters A-Z and the numbers 1-9, the lower case letters a-z and the symbols +, -, #, $, %, /, &, *, and . are returned respectively. On the 7526 Model 100, the Shift key used in conjunction with the function keys F1-F4 will return the letters a-d respectively. The Alt key used in conjunction with F1-F4 will return the letters E-H respectively.

C Format 

     #include   "cfrapi26.h"          // Defined values
 
     USHORT     KbdReadAscii(code)
 
     USHORT     *code                 // Returned code
 
     Returns:   E_OK                  // If no error occurred
                E_NO_DATA             // If no valid code in buffer

Masm Format 

     Input:     ah = 0
 
     Call:      INT 41h
 
     Returns:   bx = code
                ax = 0      If no error occurred.
                     5      If no valid code in buffer

Comments: 

The Shift key and the Alt key (Model 100 only) are used by the 7526 in
two key sequences but are not directly returned as key presses.  For
example, pressing the Shift key followed by the A key will return only 1
character (lower case a).

Only keypad make codes result in a returned character, break codes are
not returned.

If the special keypad functions Clear, Keylock, Beeper Adjustment or
Contrast Adjustment are turned on via the KbdSetMode Function, the keypad
sequences related to these functions are processed by the 7526 microcode and
no character is returned.  If these special functions are turned off, the
corresponding ASCII character is returned.

Note: 

Refer to CFRAPI26.H for key code defines.

.

Example 

#include "cfrapi26.h"
#include 


// Wait for a key to be pressed and display
// the results


int far main (int funct,char far *params)
{
  USHORT CharCount;
  UCHAR DisplayString [41];


  // Use a union for easy access to the upper and lower
     bytes of the key value.


  union
    {
      USHORT Code:                        // Full USHORT key value
      struct
        {
          UCHAR Base                      // Base character
          UCHAR Mapped;                   // File a mapped character
        } Chr;
    } Key;


  VioClear ();                            // Clear the display


  // Wait in a loop for a key to be pressed and
  // call IdleManager to allow other tasks to run


  while (KbdReadAscii (&Key.Code) != E_OK)
    IdleManger (5);                       // Wait 25 milliseconds


  if ((Key.Code == ENTER_KEY) &lor.&lor.
      (Key.Code == CLEAR_KEY) &lor.&lor.
      (Key.Code == FILL_KEY)
    {
      // The key pressed is one of the special
      // keys Enter, Fill or Clear which are processed
      // as full USHORT (2 byte) values


      VioWrtCharStr ("Special Key", 11, 0, 0, &CharCount, NO_CURSOR_MOVE);
    }
  else
    {
      // The key is a displayable character
      //
      // Show the base character (representing the physical key)
      // and the character as mapped by File a


      strcpy (DisplayString, "Base Character = x, Mapped Character = y");
      DisplayString [17] = Key.Chr.Base;
      DisplayString [39] = Key.Chr.Mapped;
      VioWrtCharStr (DisplayString, 40, 0, 0, &CharCount, NO_CURSOR_MOVE);
    }


  IdleManager (600);                      // Delay about 3 seconds to hold
  return (CONTINUE);                      // the message on the display
}

KbdSetMode

This function determines the mode in which the keypad functions Clear, Contrast Adjust, Beeper Adjust and Keylock are handled, while the CFR is executing. The CFR determines if these keys are handled automatically by the 7526 microcode or received by the CFR from keypad entries.

C Format 

     #include   "cfrapi26.h"          // Defined values
 
     USHORT   KbdSetMode(keylock_mode, clear_mode, adjustment_mode)
 
     UCHAR   keylock_mode             // keylock mode
     UCHAR   clear_mode               // clear mode
     UCHAR   adjustment_mode          // adjustment mode
 
     Returns:   E_OK                  // If no error occurred
                E_PARAM               // If parameter values are incorrect

Masm Format 

     Input:     ah = 1
                al = keylock_mode
                bh = clear_mode
                bl = adjustment_mode
 
     Call:      INT 41h
 
     Returns:   ax = 0      If no errors occurred
                   = 1      If parameter values are incorrect

Comments: 



If Clear Mode  is set to ON, pressing the Clear Key  After
termination of the CFR, the CFR receives a function code 2 restart call.
When the CFR returns from the restart call, the terminal goes to idle mode.

If Keylock Mode  is set to ON, pressing the Keylock
Key  sequence while inside a CFR results in terminating the CFR.
After termination of the CFR, keylock mode will be started to allow changing
of setup parameters or execution of diagnostics.  When the user exits
keylock mode the CFR receives a function code 2 restart call.  When the CFR
returns from the restart call, the terminal goes to idle mode.

Example 

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