v4.0/src/CMD/KEYB/KEYBI48.ASM

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   4         TITLE   DOS - KEYB Command  -  Interrupt 48H Handler
   5
   6 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
   7 ;; DOS - NLS Support - KEYB Command
   8 ;; (C) Copyright 1988 Microsoft
   9 ;;
  10 ;; File Name:  KEYBI48.ASM
  11 ;; ----------
  12 ;;
  13 ;; Description:
  14 ;; ------------
  15 ;;       Contains Interrupt 48H handler.
  16 ;;
  17 ;; Documentation Reference:
  18 ;; ------------------------
  19 ;;       PC DOS 3.3 Detailed Design Document - May ?? 1986
  20 ;;
  21 ;; Procedures Contained in This File:
  22 ;; ----------------------------------
  23 ;;
  24 ;; Include Files Required:
  25 ;; -----------------------
  26 ;;       INCLUDE KEYBEQU.INC
  27 ;;       INCLUDE KEYBSHAR.INC
  28 ;;       INCLUDE KEYBMAC.INC
  29 ;;       INCLUDE KEYBCMD.INC
  30 ;;       INCLUDE KEYBCPSD.INC
  31 ;;       INCLUDE POSTEQU.inc
  32 ;;       INCLUDE DSEG.inc
  33 ;;
  34 ;; External Procedure References:
  35 ;; ------------------------------
  36 ;;       FROM FILE  ????????.ASM:
  37 ;;            procedure - description????????????????????????????????
  38 ;;
  39 ;; Linkage Information:  Refer to file KEYB.ASM
  40 ;; --------------------
  41 ;;
  42 ;; Change History:
  43 ;; ---------------
  44 ;;
  45 ;;
  46 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  47                                        ;;
  48         INCLUDE KEYBEQU.INC            ;;
  49         INCLUDE KEYBSHAR.INC           ;;
  50         INCLUDE KEYBMAC.INC            ;;
  51         INCLUDE KEYBCMD.INC            ;;
  52         INCLUDE KEYBCPSD.INC           ;;
  53         INCLUDE POSTEQU.inc            ;;
  54         INCLUDE DSEG.inc               ;;
  55                                        ;;
  56         PUBLIC KEYB_INT_48             ;;
  57                                        ;;
  58         EXTRN  ERROR_BEEP:NEAR         ;;
  59                                        ;;
  60 CODE    SEGMENT PUBLIC 'CODE'          ;;
  61                                        ;;
  62         ASSUME  CS:CODE,DS:CODE,ES:DATA;;
  63                                        ;;
  64 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  65 ;;
  66 ;; Module: KEYB_INT_48
  67 ;;
  68 ;; Description:
  69 ;;
  70 ;; Input Registers:
  71 ;;     AL := Scan Code
  72 ;;
  73 ;; Output Registers:
  74 ;;     N/A
  75 ;;
  76 ;; Logic:
  77 ;;    IF scan code is not a break code THEN
  78 ;;       IF CNTL was not entered THEN
  79 ;;          IF ALT+SHIFT was pressed THEN
  80 ;;             Set JB_KB_FLAG in SHARED_DATA_AREA
  81 ;;             Clear ALT and SHIFT states in KB_FLAG
  82 ;;    IRET or JMP to a chained INT48 routine
  83 ;;
  84 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  85                                        ;;
  86 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  87 ;;   Program Code
  88 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
  89                                        ;;
  90 KEYB_INT_48   PROC                     ;;
  91                                        ;;
  92         STI                            ;; allow NON-KB interrupts
  93         PUSH   BX                      ;;
  94         PUSH   BP                      ;;
  95         PUSH   CX                      ;;
  96         PUSH   DX                      ;;
  97         PUSH   DI                      ;;
  98         PUSH   SI                      ;;
  99         PUSH   DS                      ;;
 100         PUSH   ES                      ;;
 101         PUSH   AX                      ;;
 102                                        ;;
 103         MOV     SD.JR_KB_FLAG,0        ;; Clear the flag
 104                                        ;;
 105         CMP     AL,80H                 ;; Test for break code
 106         JA      INT48_EXIT             ;; IF not a break code THEN
 107                                        ;;
 108         PUSH    DS                     ;; Save segment registers
 109         PUSH    ES                     ;;
 110                                        ;;
 111         PUSH    CS                     ;; Set up addressing
 112         POP     DS                     ;;  for DATA SEGMENT (=CODE SEGMENT)
 113         MOV     BX,DATA                ;; Set up addressing
 114         MOV     ES,BX                  ;;  for EXTRA SEGMENT (=BIOS RAM AREA)
 115                                        ;;
 116         MOV     AH,KB_FLAG             ;; Get the flag status
 117         AND     AH,0FH                 ;; Clear all shift states
 118                                        ;;
 119         TEST    AH,CTL_SHIFT           ;; Test if CNTL was entered?
 120         JNE     INT48_PASS             ;;;;;;;;;;;;;;;; IF yes THEN
 121                                                      ;;     pass to ROM INT48
 122         AND     AH,ALT_SHIFT+RIGHT_SHIFT+LEFT_SHIFT  ;; Test if both ALT and
 123         CMP     AH,ALT_SHIFT                         ;;     SHIFT were pressed
 124         JBE     INT48_PASS                           ;; IF no THEN
 125                                                      ;;     pass to ROM INT48
 126         MOV     BH,KB_FLAG                           ;;;;;;;;;;;; IF yes then
 127         MOV     SD.JR_KB_FLAG,BH                               ;;  Setup JR flag
 128         AND     SD.JR_KB_FLAG,ALT_SHIFT+RIGHT_SHIFT+LEFT_SHIFT ;; Pass flags
 129                                                                ;;   (ALT and
 130                                        ;;;;;;;;;;;;;;;;;;;;;;;;;; EITHER/BOTH SHIFT)
 131         XOR     KB_FLAG,AH             ;; Clear the ALT state and SHIFT state
 132                                        ;; Reset the KB_FLAG to permit
 133                                        ;;    third shifts to go through
 134 INT48_PASS:                            ;;
 135         POP     ES                     ;;
 136         POP     DS                     ;;
 137                                        ;;;;;;;
 138 INT48_EXIT:                                 ;;
 139         CMP   WORD PTR CS:SD.OLD_INT_48,0   ;; Q..are we the last in the chain?
 140         JNE   INT_48_JMP                    ;; N..call next in chain
 141         CMP   WORD PTR CS:SD.OLD_INT_48+2,0 ;; Q..are we the last in the chain?
 142         JNE   INT_48_JMP                    ;; N..call next in chain
 143                                        ;;;;;;;
 144         POP    AX                      ;; restore regs
 145         POP    ES                      ;;
 146         POP    DS                      ;;
 147         POP    SI                      ;;
 148         POP    DI                      ;;
 149         POP    DX                      ;;
 150         POP    CX                      ;;
 151         POP    BP                      ;;
 152         POP    BX                      ;;
 153                                        ;;
 154         IRET                           ;; Y..return to caller
 155                                        ;;
 156 INT_48_JMP:                            ;;
 157                                        ;;
 158         POP    AX                      ;; restore regs
 159         POP    ES                      ;;
 160         POP    DS                      ;;
 161         POP    SI                      ;;
 162         POP    DI                      ;;
 163         POP    DX                      ;;
 164         POP    CX                      ;;
 165         POP    BP                      ;;
 166         POP    BX                      ;;
 167                                        ;;
 168         JMP   CS:SD.OLD_INT_48         ;;
 169                                        ;;
 170 KEYB_INT_48   ENDP                     ;;
 171 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 172
 173 CODE   ENDS
 174        END