Category : Assembly Language Source Code
Archive   : APL2EM.ZIP
Filename : JOYSTICK.ASM

Page 58,132
Title JOYSTICK.ASM Apple Emulator Joystick Routines
;******************************************************************************
;
; Name: JOYSTICK.ASM Apple Emulator Joystick Routines
;
; Group: Emulator
;
; Revision: 1.00
;
; Date: January 30, 1988
;
; Author: Randy W. Spurlock
;
;******************************************************************************
;
; Module Functional Description:
;
; This module contains all the code for the Apple joystick
; routines.
;
;******************************************************************************
;
; Changes:
;
; DATE REVISION DESCRIPTION
; -------- -------- -------------------------------------------------------
; 1/30/88 1.00 Original
;
;******************************************************************************
Page
;
; Public Declarations
;
Public Button_1 ; Button 1 input routine (Joystick 1)
Public Button_2 ; Button 2 input routine (Joystick 1)
Public Button_3 ; Button 3 input routine
Public Joystick_1 ; Joystick 1 input routine (X-Axis)
Public Joystick_2 ; Joystick 2 input routine (Y-Axis)
Public Joystick_3 ; Joystick 3 input routine
Public Joystick_4 ; Joystick 4 input routine
Public Joystick_Strobe ; Joystick strobe routine
Public Joystick_Mode ; Joystick mode routine
Public Joystick_Type ; Joystick type routine (Analog/Binary)
Public Joystick_Fast ; Joystick fast response mode routine
Public Joystick_Center ; Joystick self-center routine
Public Joystick_Flight ; Joystick flight mode routine
Public Joystick_Reset ; Joystick reset routine
Public Joystick_Dummy ; Joystick dummy routine
Public Joy_Up_Left ; Joystick up/left routine
Public Joy_Up ; Joystick up routine
Public Joy_Up_Right ; Joystick up/right routine
Public Joy_Left ; Joystick left routine
Public Joy_Center ; Joystick center routine
Public Joy_Right ; Joystick right routine
Public Joy_Down_Left ; Joystick down/left routine
Public Joy_Down ; Joystick down routine
Public Joy_Down_Right ; Joystick down/right routine
Public Joy_X_Res_Inc ; Joystick X resolution increase
Public Joy_X_Res_Dec ; Joystick X resolution decrease
Public Joy_Y_Res_Inc ; Joystick Y resolution increase
Public Joy_Y_Res_Dec ; Joystick Y resolution decrease
Public Joy_X_Cen_Inc ; Joystick X center increase
Public Joy_X_Cen_Dec ; Joystick X center decrease
Public Joy_Y_Cen_Inc ; Joystick Y center increase
Public Joy_Y_Cen_Dec ; Joystick Y center decrease
Public Joy_Button_1 ; Joystick button 1 routine
Public Joy_Button_2 ; Joystick button 2 routine
Public Joystick_Update ; Joystick update routine
;
; External Declarations
;
Extrn Key_Status:Byte ; Keyboard status byte (KEYBOARD)
Extrn Last_Key:Byte ; Last keyboard scan code (KEYBOARD)
;
; LOCAL Equates
;
CENTER_VALUE Equ 7F00h ; Joystick center value (7Fh = 127)
START_RES Equ 0028h ; Starting resolution (0028h = 0.15625)
MIN_RES Equ 0001h ; Minimum resolution (0001h = .0039)
MAX_RES Equ 7FFFh ; Maximum resolution (7FFFh = 127.996)
MIN_CENTER Equ 00001h ; Minimum center (0001h = .0039)
MAX_CENTER Equ 0FFFFh ; Maximum center (FFFFh = 255.996)
JOY_MIN Equ 00000h ; Joystick minimum setting value
JOY_MAX Equ 0FFFFh ; Joystick maximum setting value
SMALL_RES Equ 0001h ; Small resolution change (01h = .004)
NORMAL_RES Equ 0010h ; Normal resolution change (10h = .0625)
SMALL_CENTER Equ 0100h ; Small center change value (0100 = 1)
NORMAL_CENTER Equ 0400h ; Normal center change value (0400 = 4)
RESET_MASK Equ 0FCh ; Forced reset mask (Direction/Buttons)
BUTTON_DOWN Equ 80h ; Button down indication value
CHARGED Equ 80h ; Joystick charged indication value
RESET_JOY Equ BINARY_TYPE ; Joystick reset value (Binary)
;
; Define any include files needed
;
Include Macros.inc ; Include the macro definitions
Include Equates.inc ; Include the equate definitions
.286c ; Include 80286 instructions
Page
;
; Define the emulator code segment
;
Emulate Segment Word Public 'EMULATE' ; Emulator code segment
Assume cs:Emulate, ds:Nothing, es:Nothing
Subttl Button_1 Button 1 Input Routine
Page +
;******************************************************************************
;
; Button_1() Joystick 1 Button
;
; Default to button 1 NOT down
; If button 1 is down
; Indicate that button 1 is down
; Endif for button check
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; AL - Joystick button 1 status (00h = Up, 80h = Down)
;
;******************************************************************************
Even ; Force procedure to even address
Button_1 Proc Near ; Button 1 input procedure
xor al,al ; Default to button NOT down
test cs:[Joy_Flag],BUTTON_1_DOWN
jz Button_1_Exit ; Jump if button 1 is NOT down
mov al,BUTTON_DOWN ; Indicate button 1 is down
Button_1_Exit:
ret ; Return to the caller
Button_1 Endp ; End of the Button_1 procedure
Subttl Button_2 Button 2 Input Routine
Page +
;******************************************************************************
;
; Button_2() Joystick 2 Button
;
; Default to button 2 NOT down
; If button 2 is down
; Indicate that button 2 is down
; Endif for button check
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Button_2 Proc Near ; Button 2 input procedure
xor al,al ; Default to button NOT down
test cs:[Joy_Flag],BUTTON_2_DOWN
jz Button_2_Exit ; Jump if button 2 is NOT down
mov al,BUTTON_DOWN ; Indicate button 2 is down
Button_2_Exit:
ret ; Return to the caller
Button_2 Endp ; End of the Button_2 procedure
Subttl Button_3 Button 3 Input Routine
Page +
;******************************************************************************
;
; Button_3() NOT SUPPORTED
;
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Button_3 Proc Near ; Button 3 input procedure
ret ; Return to the caller
Button_3 Endp ; End of the Button_3 procedure
Subttl Joystick_1 Joystick 1 Input Routine
Page +
;******************************************************************************
;
; Joystick_1() Joystick 1 X-Axis
;
; Save the required registers
; Default to discharged state
; If keyboard is in the joystick mode
; Get the X counter value
; If the counter value is non-zero
; Indicate in charged state
; Decrement the counter value
; Update the counter value
; Endif for non-zero counter
; Endif for keyboard in joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; AL - Joystick status (00h = Discharged, 80h = Charged)
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_1 Proc Near ; Joystick 1 input procedure
Save bx ; Save the required registers
xor al,al ; Default to discharged state
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Joy_1_Done ; Jump if NOT in joystick mode
mov bl,cs:[Joy_X_Count] ; Get the current X count value
or bl,bl ; CHeck for already discharged
jz Joy_1_Done ; Jump if already discharged
mov al,CHARGED ; Indicate joystick still charged
dec bl ; Decrement the X count value
mov cs:[Joy_X_Count],bl ; Update the X count value
Joy_1_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joystick_1 Endp ; End of the Joystick_1 procedure
Subttl Joystick_2 Joystick 2 Input Routine
Page +
;******************************************************************************
;
; Joystick_2() Joystick 2 Y-Axis
;
; Save the required registers
; Default to discharged state
; If keyboard is in the joystick mode
; Get the Y counter value
; If the counter value is non-zero
; Indicate in charged state
; Decrement the counter value
; Update the counter value
; Endif for non-zero counter
; Endif for keyboard in joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; AL - Joystick status (00h = Discharged, 80h = Charged)
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_2 Proc Near ; Joystick 2 input procedure
Save bx ; Save the required registers
xor al,al ; Default to discharged state
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Joy_1_Done ; Jump if NOT in joystick mode
mov bl,cs:[Joy_Y_Count] ; Get the current Y count value
or bl,bl ; CHeck for already discharged
jz Joy_2_Done ; Jump if already discharged
mov al,CHARGED ; Indicate joystick still charged
dec bl ; Decrement the Y count value
mov cs:[Joy_Y_Count],bl ; Update the Y count value
Joy_2_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joystick_2 Endp ; End of the Joystick_2 procedure
Subttl Joystick_3 Joystick 3 Input Routine
Page +
;******************************************************************************
;
; Joystick_3() NOT SUPPORTED
;
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_3 Proc Near ; Joystick 3 input procedure
ret ; Return to the caller
Joystick_3 Endp ; End of the Joystick_3 procedure
Subttl Joystick_4 Joystick 4 Input Routine
Page +
;******************************************************************************
;
; Joystick_4() NOT SUPPORTED
;
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_4 Proc Near ; Joystick 4 input procedure
ret ; Return to the caller
Joystick_4 Endp ; End of the Joystick_4 procedure
Subttl Joystick_Strobe Joystick Strobe Routine
Page +
;******************************************************************************
;
; Joystick_Strobe()
;
; Save the required registers
; If keyboard in joystick mode
; Get the current X position
; Get the current Y position
; Save X position as X counter
; Save Y position as Y counter
; Endif
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Strobe Proc Near ; Joystick strobe procedure
Save ax,bx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Strobe_Done ; Jump if NOT in joystick mode
mov ax,cs:[Joy_X_Pos] ; Get the current X position
mov bx,cs:[Joy_Y_Pos] ; Get the current Y position
mov cs:[Joy_X_Count],ah ; Save X position as the X count value
mov cs:[Joy_Y_Count],bh ; Save Y position as the Y count value
Strobe_Done:
Restore ax,bx ; Restore the required registers
ret ; Return to the caller
Joystick_Strobe Endp ; End of the Joystick_Strobe procedure
Subttl Joystick_Fast Joystick Fast Response Mode Routine
Page +
;******************************************************************************
;
; Joystick_Fast(Scan_Code)
;
; If the last scan code does NOT match (NOT a repeat)
; If this is a make code
; Toggle the joystick fast response mode bit
; Endif
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Fast Proc Near ; Joystick fast response mode procedure
cmp ah,cs:[Last_Key] ; Check for a repeat scan code
je Fast_Done ; Jump if this key is repeating
or ah,ah ; Check for a make or break code
js Fast_Done ; Jump if this is a break code
xor Byte Ptr cs:[Joy_Flag],FAST_MODE
Fast_Done:
ret ; Return to the caller
Joystick_Fast Endp ; End of the Joystick_Fast procedure
Subttl Joystick_Center Joystick Self-Center Mode Routine
Page +
;******************************************************************************
;
; Joystick_Center(Scan_Code)
;
; If the last scan code does NOT match (NOT a repeat)
; If this is a make code
; Toggle the joystick self-center mode bit
; Endif
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Center Proc Near ; Joystick self-center mode procedure
cmp ah,cs:[Last_Key] ; Check for a repeat scan code
je Self_Done ; Jump if this key is repeating
or ah,ah ; Check for a make or break code
js Self_Done ; Jump if this is a break code
xor Byte Ptr cs:[Joy_Flag],SELF_CENTER
Self_Done:
ret ; Return to the caller
Joystick_Center Endp ; End of the Joystick_Center procedure
Subttl Joystick_Flight Joystick Flight Mode Routine
Page +
;******************************************************************************
;
; Joystick_Flight(Scan_Code)
;
; If the last scan code does NOT match (NOT a repeat)
; If this is a make code
; Toggle the joystick flight mode bit
; Endif
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Flight Proc Near ; Joystick flight mode procedure
cmp ah,cs:[Last_Key] ; Check for a repeat scan code
je Flight_Done ; Jump if this key is repeating
or ah,ah ; Check for a make or break code
js Flight_Done ; Jump if this is a break code
xor Byte Ptr cs:[Joy_Flag],FLIGHT_MODE
Flight_Done:
ret ; Return to the caller
Joystick_Flight Endp ; End of the Joystick_Flight procedure
Subttl Joystick_Reset Joystick Reset Routine
Page +
;******************************************************************************
;
; Joystick_Reset(Scan_Code)
;
; If the last scan code does NOT match (NOT a repeat)
; If this is a make code
; Reset joystick position to center
; Reset joystick center values
; Reset joystick X/Y resolutions
; Reset joystick type & mode values
; Reset the joystick status
; Endif
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Reset Proc Near ; Joystick reset procedure
cmp ah,cs:[Last_Key] ; Check for a repeat scan code
je Reset_Done ; Jump if this key is repeating
or ah,ah ; Check for a make or break code
js Reset_Done ; Jump if this is a break code
mov cs:[Joy_X_Pos],CENTER_VALUE
mov cs:[Joy_Y_Pos],CENTER_VALUE
mov cs:[Joy_X_Center],CENTER_VALUE
mov cs:[Joy_Y_Center],CENTER_VALUE
mov cs:[Joy_X_Res],START_RES
mov cs:[Joy_Y_Res],START_RES
mov Byte Ptr cs:[Joy_Flag],RESET_JOY
Reset_Done:
ret ; Return to the caller
Joystick_Reset Endp ; End of the Joystick_Reset procedure
Subttl Joystick_Mode Joystick Mode Routine
Page +
;******************************************************************************
;
; Joystick_Mode(Scan_Code)
;
; If the last scan code does NOT match (NOT a repeat)
; If this is a make code
; Reset joystick status (Direction and buttons)
; Endif
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Mode Proc Near ; Joystick mode procedure
cmp ah,cs:[Last_Key] ; Check for a repeat scan code
je Mode_Done ; Jump if this key is repeating
or ah,ah ; Check for a make or break code
js Mode_Done ; Jump if this is a break code
and Byte Ptr cs:[Joy_Flag],RESET_MASK
Mode_Done:
ret ; Return to the caller
Joystick_Mode Endp ; End of the Joystick_Mode procedure
Subttl Joystick_Type Joystick Type Routine
Page +
;******************************************************************************
;
; Joystick_Type(Scan_Code)
;
; If the last scan code does NOT match (NOT a repeat)
; If this is a make code
; Toggle the joystick type bit
; Endif
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Type Proc Near ; Joystick type procedure
cmp ah,cs:[Last_Key] ; Check for a repeat scan code
je Type_Done ; Jump if this key is repeating
or ah,ah ; Check for a make or break code
js Type_Done ; Jump if this is a break code
xor Byte Ptr cs:[Joy_Flag],BINARY_TYPE
Type_Done:
ret ; Return to the caller
Joystick_Type Endp ; End of the Joystick_Type procedure
Subttl Joystick_Dummy Joystick Dummy Routine
Page +
;******************************************************************************
;
; Joystick_Dummy()
;
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Dummy Proc Near ; Joystick dummy procedure
ret ; Return to the caller
Joystick_Dummy Endp ; End of the Joystick_Dummy procedure
Subttl Joy_Up_Left Joystick Up/Left Routine
Page +
;******************************************************************************
;
; Joy_Up_Left(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the up/left flag bit
; If joystick type is binary
; Set joystick X position to JOY_MIN
; Set joystick Y position to JOY_MIN
; Else
; If joystick mode is fast response
; If X position is > X center value
; Set X position to X center value
; Endif
; If Y position is > Y center value
; Set Y position to Y center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the up/left flag bit
; If this is self-center mode
; Set joystick X position to X center value
; Set joystick Y position to Y center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Up_Left Proc Near ; Joystick up/left procedure
Save bx,cx ; Save the required registers
or ah,ah ; Check for a make or break code
js Up_Left_Break ; Jump if this is a break code
Up_Left_Make:
or Byte Ptr cs:[Joy_Status],UP_LEFT
mov bx,cs:[Joy_X_Pos] ; Get the current joystick X position
mov cx,cs:[Joy_Y_Pos] ; Get the current joystick Y position
test cs:[Joy_Flag],BINARY_TYPE
jz Up_Left_Check ; Jump if NOT in binary mode
mov bx,JOY_MIN ; Set X position to joystick minimum
mov cx,JOY_MIN ; Set Y position to joystick minimum
jmp Short Up_Left_Update ; Go update the X and Y positions
Up_Left_Check:
test cs:[Joy_Flag],FAST_MODE
jz Up_Left_Done ; Jump if NOT in fast response mode
cmp bx,cs:[Joy_X_Center] ; Check the current X position value
jbe Up_Left_Test ; Jump if already moving left
mov bx,cs:[Joy_X_Center] ; Center the joystick X position
Up_Left_Test:
cmp cx,cs:[Joy_Y_Center] ; Check the current Y position value
jbe Up_Left_Update ; Jump if already moving up
mov cx,cs:[Joy_Y_Center] ; Center the joystick Y position
Up_Left_Update:
mov cs:[Joy_X_Pos],bx ; Update the current X position value
mov cs:[Joy_Y_Pos],cx ; Update the current Y position value
jmp Short Up_Left_Done ; Go return to the caller
Up_Left_Break:
and Byte Ptr cs:[Joy_Status],Not UP_LEFT
test cs:[Joy_Flag],SELF_CENTER
jz Up_Left_Done ; Jump if NOT in self-center mode
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Up_Left_Done:
Restore bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_Up_Left Endp ; End of the Joy_Up_Left procedure
Subttl Joy_Up Joystick Up Routine
Page +
;******************************************************************************
;
; Joy_Up(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the up flag bit
; If joystick type is binary
; If joystick mode is NOT flight mode
; Set joystick X pos. to X center value
; Endif
; Set joystick Y position to JOY_MIN
; Else
; If joystick mode is fast response
; If Y position is > Y center value
; Set Y position to Y center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the up flag bit
; If this is self-center mode
; Set joystick Y position to Y center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Up Proc Near ; Joystick up procedure
Save cx ; Save the required registers
or ah,ah ; Check for a make or break code
js Up_Break ; Jump if this is a break code
Up_Make:
or Byte Ptr cs:[Joy_Status],UP
mov cx,cs:[Joy_Y_Pos] ; Get the current joystick Y position
test cs:[Joy_Flag],BINARY_TYPE
jz Up_Check ; Jump if NOT in binary mode
test cs:[Joy_Flag],FLIGHT_MODE
jnz Up_Binary ; Jump if in flight mode
mov cx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],cx ; Set X position to center value
Up_Binary:
mov cx,JOY_MIN ; Set Y position to joystick minimum
jmp Short Up_Update ; Go update the Y position
Up_Check:
test cs:[Joy_Flag],FAST_MODE
jz Up_Done ; Jump if NOT in fast response mode
cmp cx,cs:[Joy_Y_Center] ; Check the current Y position value
jbe Up_Update ; Jump if already moving up
mov cx,cs:[Joy_Y_Center] ; Center the joystick Y position
Up_Update:
mov cs:[Joy_Y_Pos],cx ; Update the current Y position value
jmp Short Up_Done ; Go return to the caller
Up_Break:
and Byte Ptr cs:[Joy_Status],Not UP
test cs:[Joy_Flag],SELF_CENTER
jz Up_Done ; Jump if NOT in self-center mode
mov cx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],cx ; Set Y position to center value
Up_Done:
Restore cx ; Restore the required registers
ret ; Return to the caller
Joy_Up Endp ; End of the Joy_Up procedure
Subttl Joy_Up_Right Joystick Up/Right Routine
Page +
;******************************************************************************
;
; Joy_Up_Right(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the up/right flag bit
; If joystick type is binary
; Set joystick X position to JOY_MAX
; Set joystick Y position to JOY_MIN
; Else
; If joystick mode is fast response
; If X position is <= X center value
; Set X position to X center value
; Endif
; If Y position is > Y center value
; Set Y position to Y center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the up/right flag bit
; If this is self-center mode
; Set joystick X position to X center value
; Set joystick Y position to Y center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Up_Right Proc Near ; Joystick up/right procedure
Save bx,cx ; Save the required registers
or ah,ah ; Check for a make or break code
js Up_Right_Break ; Jump if this is a break code
Up_Right_Make:

or Byte Ptr cs:[Joy_Status],UP_RIGHT
mov bx,cs:[Joy_X_Pos] ; Get the current joystick X position
mov cx,cs:[Joy_Y_Pos] ; Get the current joystick Y position
test cs:[Joy_Flag],BINARY_TYPE
jz Up_Right_Check ; Jump if NOT in binary mode
mov bx,JOY_MAX ; Set X position to joystick maximum
mov cx,JOY_MIN ; Set Y position to joystick minimum
jmp Short Up_Right_Update ; Go update the X and Y positions
Up_Right_Check:
test cs:[Joy_Flag],FAST_MODE
jz Up_Right_Done ; Jump if NOT in fast response mode
cmp bx,cs:[Joy_X_Center] ; Check the current X position value
ja Up_Right_Test ; Jump if already moving right
mov bx,cs:[Joy_X_Center] ; Center the joystick X position
Up_Right_Test:
cmp cx,cs:[Joy_Y_Center] ; Check the current Y position value
jbe Up_Right_Update ; Jump if already moving up
mov cx,cs:[Joy_Y_Center] ; Center the joystick Y position
Up_Right_Update:
mov cs:[Joy_X_Pos],bx ; Update the current X position value
mov cs:[Joy_Y_Pos],cx ; Update the current Y position value
jmp Short Up_Right_Done ; Go return to the caller
Up_Right_Break:
and Byte Ptr cs:[Joy_Status],Not UP_RIGHT
test cs:[Joy_Flag],SELF_CENTER
jz Up_Right_Done ; Jump if NOT in self-center mode
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Up_Right_Done:
Restore bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_Up_Right Endp ; End of the Joy_Up_Right procedure
Subttl Joy_Left Joystick Left Routine
Page +
;******************************************************************************
;
; Joy_Left(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the left flag bit
; If joystick type is binary
; If joystick mode is NOT flight mode
; Set joystick Y pos. to Y center value
; Endif
; Set joystick X position to JOY_MIN
; Else
; If joystick mode is fast response
; If X position is > X center value
; Set X position to X center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the up flag bit
; If this is self-center mode
; Set joystick X position to X center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Left Proc Near ; Joystick left procedure
Save bx ; Save the required registers
or ah,ah ; Check for a make or break code
js Left_Break ; Jump if this is a break code
Left_Make:
or Byte Ptr cs:[Joy_Status],LEFT
mov bx,cs:[Joy_X_Pos] ; Get the current joystick X position
test cs:[Joy_Flag],BINARY_TYPE
jz Left_Check ; Jump if NOT in binary mode
test cs:[Joy_Flag],FLIGHT_MODE
jnz Left_Binary ; Jump if in flight mode
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Left_Binary:
mov bx,JOY_MIN ; Set X position to joystick minimum
jmp Short Left_Update ; Go update the X position
Left_Check:
test cs:[Joy_Flag],FAST_MODE
jz Left_Done ; Jump if NOT in fast response mode
cmp bx,cs:[Joy_X_Center] ; Check the current X position value
jbe Left_Update ; Jump if already moving left
mov bx,cs:[Joy_X_Center] ; Center the joystick X position
Left_Update:
mov cs:[Joy_X_Pos],bx ; Update the current X position value
jmp Short Left_Done ; Go return to the caller
Left_Break:
and Byte Ptr cs:[Joy_Status],Not LEFT
test cs:[Joy_Flag],SELF_CENTER
jz Left_Done ; Jump if NOT in self-center mode
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
Left_Done:
Restore cx ; Restore the required registers
ret ; Return to the caller
Joy_Left Endp ; End of the Joy_Left procedure
Subttl Joy_Center Joystick Center Routine
Page +
;******************************************************************************
;
; Joy_Center(Scan_Code)
;
; Save the required registers
; If this is a make code
; Center the joystick X and Y positions
; Endif
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Center Proc Near ; Joystick center procedure
Save bx ; Save the required registers
or ah,ah ; Check for a make or break code
js Center_Done ; Jump if this is a break code
Center_Make:
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Center_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joy_Center Endp ; End of the Joy_Center procedure
Subttl Joy_Right Joystick Right Routine
Page +
;******************************************************************************
;
; Joy_Right(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the right flag bit
; If joystick type is binary
; If joystick mode is NOT flight mode
; Set joystick Y pos. to Y center value
; Endif
; Set joystick X position to JOY_MAX
; Else
; If joystick mode is fast response
; If X position is <= X center value
; Set X position to X center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the up flag bit
; If this is self-center mode
; Set joystick X position to X center value

; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Right Proc Near ; Joystick right procedure
Save bx ; Save the required registers
or ah,ah ; Check for a make or break code
js Right_Break ; Jump if this is a break code
Right_Make:
or Byte Ptr cs:[Joy_Status],RIGHT
mov bx,cs:[Joy_X_Pos] ; Get the current joystick X position
test cs:[Joy_Flag],BINARY_TYPE
jz Right_Check ; Jump if NOT in binary mode
test cs:[Joy_Flag],FLIGHT_MODE
jnz Right_Binary ; Jump if in flight mode
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Right_Binary:
mov bx,JOY_MAx ; Set X position to joystick maximum
jmp Short Right_Update ; Go update the X position
Right_Check:
test cs:[Joy_Flag],FAST_MODE
jz Right_Done ; Jump if NOT in fast response mode
cmp bx,cs:[Joy_X_Center] ; Check the current X position value
ja Right_Update ; Jump if already moving right
mov bx,cs:[Joy_X_Center] ; Center the joystick X position
Right_Update:
mov cs:[Joy_X_Pos],bx ; Update the current X position value
jmp Short Right_Done ; Go return to the caller
Right_Break:
and Byte Ptr cs:[Joy_Status],Not RIGHT
test cs:[Joy_Flag],SELF_CENTER
jz Right_Done ; Jump if NOT in self-center mode
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
Right_Done:
Restore cx ; Restore the required registers
ret ; Return to the caller
Joy_Right Endp ; End of the Joy_Right procedure
Subttl Joy_Down_Left Joystick Down/Left Routine
Page +
;******************************************************************************
;
; Joy_Down_Left(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the down/left flag bit
; If joystick type is binary
; Set joystick X position to JOY_MIN
; Set joystick Y position to JOY_MAX
; Else
; If joystick mode is fast response
; If X position is > X center value
; Set X position to X center value
; Endif
; If Y position is <= Y center value
; Set Y position to Y center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the down/left flag bit
; If this is self-center mode
; Set joystick X position to X center value
; Set joystick Y position to Y center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Down_Left Proc Near ; Joystick down/left procedure
Save bx,cx ; Save the required registers
or ah,ah ; Check for a make or break code
js Down_Left_Break ; Jump if this is a break code
Down_Left_Make:
or Byte Ptr cs:[Joy_Status],DOWN_LEFT
mov bx,cs:[Joy_X_Pos] ; Get the current joystick X position
mov cx,cs:[Joy_Y_Pos] ; Get the current joystick Y position
test cs:[Joy_Flag],BINARY_TYPE
jz Down_Left_Check ; Jump if NOT in binary mode
mov bx,JOY_MIN ; Set X position to joystick minimum
mov cx,JOY_MAX ; Set Y position to joystick maximum
jmp Short Down_Left_Update ; Go update the X and Y positions
Down_Left_Check:
test cs:[Joy_Flag],FAST_MODE
jz Down_Left_Done ; Jump if NOT in fast response mode
cmp bx,cs:[Joy_X_Center] ; Check the current X position value
jbe Down_Left_Test ; Jump if already moving left
mov bx,cs:[Joy_X_Center] ; Center the joystick X position
Down_Left_Test:
cmp cx,cs:[Joy_Y_Center] ; Check the current Y position value
ja Down_Left_Update ; Jump if already moving down
mov cx,cs:[Joy_Y_Center] ; Center the joystick Y position
Down_Left_Update:
mov cs:[Joy_X_Pos],bx ; Update the current X position value
mov cs:[Joy_Y_Pos],cx ; Update the current Y position value
jmp Short Down_Left_Done ; Go return to the caller
Down_Left_Break:
and Byte Ptr cs:[Joy_Status],Not DOWN_LEFT
test cs:[Joy_Flag],SELF_CENTER
jz Down_Left_Done ; Jump if NOT in self-center mode
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Down_Left_Done:
Restore bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_Down_Left Endp ; End of the Joy_Down_Left procedure
Subttl Joy_Down Joystick Down Routine
Page +
;******************************************************************************
;
; Joy_Down(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the down flag bit
; If joystick type is binary
; If joystick mode is NOT flight mode
; Set joystick X pos. to X center value
; Endif
; Set joystick Y position to JOY_MAX
; Else
; If joystick mode is fast response
; If Y position is <= X center value
; Set Y position to Y center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the down flag bit
; If this is self-center mode
; Set joystick Y position to Y center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Down Proc Near ; Joystick down procedure
Save cx ; Save the required registers
or ah,ah ; Check for a make or break code
js Down_Break ; Jump if this is a break code
Down_Make:
or Byte Ptr cs:[Joy_Status],DOWN
mov cx,cs:[Joy_Y_Pos] ; Get the current joystick Y position
test cs:[Joy_Flag],BINARY_TYPE
jz Down_Check ; Jump if NOT in binary mode
test cs:[Joy_Flag],FLIGHT_MODE
jnz Down_Binary ; Jump if in flight mode
mov cx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],cx ; Set X position to center value
Down_Binary:
mov cx,JOY_MAX ; Set Y position to joystick maximum
jmp Short Down_Update ; Go update the Y position
Down_Check:
test cs:[Joy_Flag],FAST_MODE
jz Down_Done ; Jump if NOT in fast response mode
cmp cx,cs:[Joy_Y_Center] ; Check the current Y position value
ja Down_Update ; Jump if already moving down
mov cx,cs:[Joy_Y_Center] ; Center the joystick Y position
Down_Update:
mov cs:[Joy_Y_Pos],cx ; Update the current Y position value
jmp Short Down_Done ; Go return to the caller
Down_Break:
and Byte Ptr cs:[Joy_Status],Not DOWN
test cs:[Joy_Flag],SELF_CENTER
jz Down_Done ; Jump if NOT in self-center mode
mov cx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],cx ; Set Y position to center value
Down_Done:
Restore cx ; Restore the required registers
ret ; Return to the caller
Joy_Down Endp ; End of the Joy_Down procedure
Subttl Joy_Down_Right Joystick Down/Right Routine
Page +
;******************************************************************************
;
; Joy_Down_Right(Scan_Code)
;
; Save the required registers
; If this is a make code
; Set the down/right flag bit
; If joystick type is binary
; Set joystick X position to JOY_MAX
; Set joystick Y position to JOY_MAX
; Else
; If joystick mode is fast response
; If X position is <= X center value
; Set X position to X center value
; Endif
; If Y position is <= Y center value
; Set Y position to Y center value
; Endif
; Endif for joystick fast response mode
; Endif for joystick type binary
; Else this is a break code
; Reset the down/right flag bit
; If this is self-center mode
; Set joystick X position to X center value
; Set joystick Y position to Y center value
; Endif for self-center mode
; Endif for scan code
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Down_Right Proc Near ; Joystick down/right procedure
Save bx,cx ; Save the required registers
or ah,ah ; Check for a make or break code
js Down_Right_Break ; Jump if this is a break code
Down_Right_Make:
or Byte Ptr cs:[Joy_Status],DOWN_RIGHT
mov bx,cs:[Joy_X_Pos] ; Get the current joystick X position
mov cx,cs:[Joy_Y_Pos] ; Get the current joystick Y position
test cs:[Joy_Flag],BINARY_TYPE
jz Down_Right_Check ; Jump if NOT in binary mode
mov bx,JOY_MAX ; Set X position to joystick maximum
mov cx,JOY_MAX ; Set Y position to joystick maximum
jmp Short Down_Right_Update ; Go update the X and Y positions
Down_Right_Check:
test cs:[Joy_Flag],FAST_MODE
jz Down_Right_Done ; Jump if NOT in fast response mode
cmp bx,cs:[Joy_X_Center] ; Check the current X position value
ja Down_Right_Test ; Jump if already moving right
mov bx,cs:[Joy_X_Center] ; Center the joystick X position
Down_Right_Test:
cmp cx,cs:[Joy_Y_Center] ; Check the current Y position value
ja Down_Right_Update ; Jump if already moving down
mov cx,cs:[Joy_Y_Center] ; Center the joystick Y position
Down_Right_Update:
mov cs:[Joy_X_Pos],bx ; Update the current X position value
mov cs:[Joy_Y_Pos],cx ; Update the current Y position value
jmp Short Down_Right_Done ; Go return to the caller
Down_Right_Break:
and Byte Ptr cs:[Joy_Status],Not DOWN_RIGHT
test cs:[Joy_Flag],SELF_CENTER
jz Down_Right_Done ; Jump if NOT in self-center mode
mov bx,cs:[Joy_X_Center] ; Get the current X center value
mov cs:[Joy_X_Pos],bx ; Set X position to center value
mov bx,cs:[Joy_Y_Center] ; Get the current Y center value
mov cs:[Joy_Y_Pos],bx ; Set Y position to center value
Down_Right_Done:
Restore bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_Down_Right Endp ; End of the Joy_Down_Right procedure
Subttl Joy_X_Res_Inc Joystick X Resolution Increase Routine
Page +
;******************************************************************************
;
; Joy_X_Res_Inc(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small X resolution increment
; Else
; Do a normal X resolution increment
; Endif
; Make sure X resolution is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_X_Res_Inc Proc Near ; Joystick X resolution inc. procedure
Save bx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz X_Res_Inc_Done ; Jump if NOT in joystick mode
or ah,ah ; Check for a make or break code
js X_Res_Inc_Done ; Jump if this is a break code
mov bx,cs:[Joy_X_Res] ; Get the current X resolution value
test cs:[Key_Status],SHIFTED ; Check for shift key down
jz Do_X_Res_Inc ; Jump if shift key is NOT held down
add bx,SMALL_RES ; Add small change value to resolution
jmp Short X_Res_Inc_Check ; Go check the X resolution value
Do_X_Res_Inc:
add bx,NORMAL_RES ; Add normal change value to resolution
X_Res_Inc_Check:
jc X_Res_Inc_Bad ; Jump if X increment is bad
cmp bx,MAX_RES ; Check against maximum resolution
jbe X_Res_Inc_Update ; Go update X resolution if in range
X_Res_Inc_Bad:
mov bx,MAX_RES ; Set X resolution to maximum value
X_Res_Inc_Update:
mov cs:[Joy_X_Res],bx ; Update the X resolution value
X_Res_Inc_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joy_X_Res_Inc Endp ; End of the Joy_X_Res_Inc procedure
Subttl Joy_X_Res_Dec Joystick X Resolution Decrease Routine
Page +
;******************************************************************************
;
; Joy_X_Res_Dec(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small X resolution decrement
; Else
; Do a normal X resolution decrement
; Endif
; Make sure X resolution is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_X_Res_Dec Proc Near ; Joystick X resolution dec. procedure
Save bx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz X_Res_Dec_Done ; Jump if NOT in joystick mode
or ah,ah ; Check for a make or break code
js X_Res_Dec_Done ; Jump if this is a break code
mov bx,cs:[Joy_X_Res] ; Get the current X resolution value
test cs:[Key_Status],SHIFTED ; Check for Shift key down
jz Do_X_Res_Dec ; Jump if shift key is NOT held down
sub bx,SMALL_RES ; Subtract small change value
jmp Short X_Res_Dec_Check ; Go check the X resolution value
Do_X_Res_Dec:
sub bx,NORMAL_RES ; Subtract normal change value
X_Res_Dec_Check:
jc X_Res_Dec_Bad ; Jump if X decrement is bad
cmp bx,MIN_RES ; Check against minimum resolution
jae X_Res_Dec_Update ; Go update X resolution if in range
X_Res_Dec_Bad:
mov bx,MIN_RES ; Set X resolution to minimum value
X_Res_Dec_Update:
mov cs:[Joy_X_Res],bx ; Update the X resolution value
X_Res_Dec_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joy_X_Res_Dec Endp ; End of the Joy_X_Res_Dec procedure
Subttl Joy_Y_Res_Inc Joystick Y Resolution Increase Routine
Page +
;******************************************************************************
;
; Joy_Y_Res_Inc(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small Y resolution increment
; Else
; Do a normal Y resolution increment
; Endif
; Make sure Y resolution is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Y_Res_Inc Proc Near ; Joystick Y resolution inc. procedure
Save bx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Y_Res_Inc_Done ; Jump if NOT in joystick mode
or ah,ah ; Check for a make or break code
js Y_Res_Inc_Done ; Jump if this is a break code
mov bx,cs:[Joy_Y_Res] ; Get the current Y resolution value
test cs:[Key_Status],SHIFTED ; Check for shift key down
jz Do_Y_Res_Inc ; Jump if shift key is NOT held down
add bx,SMALL_RES ; Add small change value to resolution
jmp Short Y_Res_Inc_Check ; Go check the Y resolution value
Do_Y_Res_Inc:
add bx,NORMAL_RES ; Add normal change value to resolution
Y_Res_Inc_Check:
jc Y_Res_Inc_Bad ; Jump if Y increment is bad
cmp bx,MAX_RES ; Check against maximum resolution
jbe Y_Res_Inc_Update ; Go update Y resolution if in range
Y_Res_Inc_Bad:
mov bx,MAX_RES ; Set Y resolution to maximum value
Y_Res_Inc_Update:
mov cs:[Joy_Y_Res],bx ; Update the Y resolution value
Y_Res_Inc_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joy_Y_Res_Inc Endp ; End of the Joy_Y_Res_Inc procedure
Subttl Joy_Y_Res_Dec Joystick Y Resolution Decrease Routine
Page +
;******************************************************************************
;
; Joy_Y_Res_Dec(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small Y resolution decrement
; Else
; Do a normal Y resolution decrement
; Endif
; Make sure Y resolution is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Y_Res_Dec Proc Near ; Joystick Y resolution dec. procedure
Save bx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Y_Res_Dec_Done ; Jump if NOT joystick mode
or ah,ah ; Check for a make or break code
js Y_Res_Dec_Done ; Jump if this is a break code
mov bx,cs:[Joy_Y_Res] ; Get the current Y resolution value
test cs:[Key_Status],SHIFTED ; Check for shift key down
jz Do_Y_Res_Dec ; Jump if shift key is NOT held down
sub bx,SMALL_RES ; Subtract small change value
jmp Short Y_Res_Dec_Check ; Go check the Y resolution value
Do_Y_Res_Dec:
sub bx,NORMAL_RES ; Subtract normal change value
Y_Res_Dec_Check:
jc Y_Res_Dec_Bad ; Jump if Y decrement is bad
cmp bx,MIN_RES ; Check against minimum resolution
jae Y_Res_Dec_Update ; Go update Y resolution if in range
Y_Res_Dec_Bad:
mov bx,MIN_RES ; Set Y resolution to minimum value
Y_Res_Dec_Update:
mov cs:[Joy_Y_Res],bx ; Update the Y resolution value
Y_Res_Dec_Done:
Restore bx ; Restore the required registers
ret ; Return to the caller
Joy_Y_Res_Dec Endp ; End of the Joy_Y_Res_Dec procedure
Subttl Joy_X_Cen_Inc Joystick X Center Increase Routine
Page +
;******************************************************************************
;
; Joy_X_Cen_Inc(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small X center increment
; Do a small X position increment
; Else
; Do a normal X center increment
; Do a normal X position increment
; Endif
; Make sure X center is in range
; make sure X position is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_X_Cen_Inc Proc Near ; Joystick X center increment procedure
Save bx,cx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz X_Cen_Inc_Done ; Jump if NOT in joystick mode
or ah,ah ; Check for a make or break code
js X_Cen_Inc_Done ; Jump if this is a break code
test cs:[Key_Status],SHIFTED ; Check for shift key down
jz Do_X_Cen_Inc ; Jump if shift key is NOT held down
mov bx,SMALL_CENTER ; Setup small change value for center
mov cx,SMALL_CENTER ; Setup small change value for position
jmp Short X_Cen_Inc_Check ; Go check the X center value
Do_X_Cen_Inc:
mov bx,NORMAL_CENTER ; Setup normal change value for center
mov cx,NORMAL_CENTER ; Setup normal change value for position
X_Cen_Inc_Check:
add bx,cs:[Joy_X_Center] ; Compute the new X center value
jc X_Cen_Inc_Bad ; Jump if X increment is bad
cmp bx,MAX_CENTER ; Check against maximum center
jbe X_Cen_Inc_Update ; Go update X center if in range
X_Cen_Inc_Bad:
mov bx,MAX_CENTER ; Set X center to maximum value
X_Cen_Inc_Update:
mov cs:[Joy_X_Center],bx ; Update the X center value
X_Pos_Inc_Check:
add cx,cs:[Joy_X_Pos] ; Compute the new X position value
jnc X_Pos_Inc_Update ; Jump if X position is ok
mov cx,JOY_MAX ; Setup X position to maximum
X_Pos_Inc_Update:
mov cs:[Joy_X_Pos],cx ; Update the X position value
X_Cen_Inc_Done:
Restore bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_X_Cen_Inc Endp ; End of the Joy_X_Cen_Inc procedure
Subttl Joy_X_Cen_Dec Joystick X Center Decrease Routine
Page +
;******************************************************************************
;
; Joy_X_Cen_Dec(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small X center decrement
; Do a small X position decrement
; Else
; Do a normal X center decrement
; Do a normal X position decrement
; Endif
; Make sure X center is in range
; Make sure X position is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_X_Cen_Dec Proc Near ; Joystick X center decrement procedure
Save ax,bx,cx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz X_Cen_Dec_Done ; Jump if NOT in joystick mode
or ah,ah ; Check for a make or break code
js X_Cen_Dec_Done ; Jump if this is a break code
test cs:[Key_Status],SHIFTED ; Check for Shift key down
jz Do_X_Cen_Dec ; Jump if shift key is NOT held down
mov bx,SMALL_CENTER ; Setup small change value for center
mov cx,SMALL_CENTER ; Setup small change value for position
jmp Short X_Cen_Dec_Check ; Go check the X center value
Do_X_Cen_Dec:
mov bx,NORMAL_CENTER ; Setup normal change value for center
mov cx,NORMAL_CENTER ; Setup normal change value for position
X_Cen_Dec_Check:
mov ax,cs:[Joy_X_Center] ; Get the current X center value
sub ax,bx ; Compute the new X center value
jc X_Cen_Dec_Bad ; Jump if X decrement is bad
cmp ax,MIN_CENTER ; Check against minimum center
jae X_Cen_Dec_Update ; Go update X center if in range
X_Cen_Dec_Bad:
mov ax,MIN_CENTER ; Set X center to minimum value
X_Cen_Dec_Update:
mov cs:[Joy_X_Center],ax ; Update the X center value
X_Pos_Dec_Check:
mov ax,cs:[Joy_X_Pos] ; Get the current X position value
sub ax,cx ; Compute the new X position value
jnc X_Pos_Dec_Update ; Jump if X position is ok
mov ax,JOY_MIN ; Setup X position to minimum
X_Pos_Dec_Update:
mov cs:[Joy_X_Pos],ax ; Update the X position value
X_Cen_Dec_Done:
Restore ax,bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_X_Cen_Dec Endp ; End of the Joy_X_Cen_Dec procedure
Subttl Joy_Y_Cen_Inc Joystick Y Center Increase Routine
Page +
;******************************************************************************
;
; Joy_Y_Cen_Inc(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small Y center increment
; Do a small Y position increment
; Else
; Do a normal Y center increment
; Do a normal Y position increment
; Endif
; Make sure Y center is in range
; Make sure Y position is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Y_Cen_Inc Proc Near ; Joystick Y center increment procedure
Save bx,cx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Y_Cen_Inc_Done ; Jump if NOT in joystick mode
or ah,ah ; Check for a make or break code
js Y_Cen_Inc_Done ; Jump if this is a break code
test cs:[Key_Status],SHIFTED ; Check for shift key down
jz Do_Y_Cen_Inc ; Jump if shift key is NOT held down
mov bx,SMALL_CENTER ; Setup small change value for center
mov cx,SMALL_CENTER ; Setup small change value for position
jmp Short Y_Cen_Inc_Check ; Go check the Y center value
Do_Y_Cen_Inc:
mov bx,NORMAL_CENTER ; Setup normal change value for center
mov cx,NORMAL_CENTER ; Setup normal change value for position
Y_Cen_Inc_Check:
add bx,cs:[Joy_Y_Center] ; Compute the new Y center value
jc Y_Cen_Inc_Bad ; Jump if Y increment is bad
cmp bx,MAX_CENTER ; Check against maximum center
jbe Y_Cen_Inc_Update ; Go update Y center if in range
Y_Cen_Inc_Bad:
mov bx,MAX_CENTER ; Set Y center to maximum value
Y_Cen_Inc_Update:
mov cs:[Joy_Y_Center],bx ; Update the Y center value
Y_Pos_Inc_Check:
add cx,cs:[Joy_Y_Pos] ; Compute the new Y position value
jnc Y_Pos_Inc_Update ; Jump if Y position is ok
mov cx,JOY_MAX ; Setup Y position to maximum
Y_Pos_Inc_Update:
mov cs:[Joy_Y_Pos],cx ; Update the Y position value
Y_Cen_Inc_Done:
Restore bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_Y_Cen_Inc Endp ; End of the Joy_Y_Cen_Inc procedure
Subttl Joy_Y_Cen_Dec Joystick Y Center Decrease Routine
Page +
;******************************************************************************
;
; Joy_Y_Cen_Dec(Scan_Code)
;
; Save the required registers
; If this is joystick mode
; If this is a make code
; If the shift key is down
; Do a small Y center decrement
; Do a small Y position decrement
; Else
; Do a normal Y center decrement
; Do a normal Y position decrement
; Endif
; Make sure Y center is in range
; Make sure Y position is in range
; Endif this is a break code
; Endif for joystick mode
; Restore the required registers
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Y_Cen_Dec Proc Near ; Joystick Y center decrement procedure
Save ax,bx,cx ; Save the required registers
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Y_Cen_Dec_Done ; Jump if NOT joystick mode
or ah,ah ; Check for a make or break code
js Y_Cen_Dec_Done ; Jump if this is a break code
test cs:[Key_Status],SHIFTED ; Check for shift key down
jz Do_Y_Cen_Dec ; Jump if shift key is NOT held down
mov bx,SMALL_CENTER ; Setup small change value for center
mov cx,SMALL_CENTER ; Setup small change value for position
jmp Short Y_Cen_Dec_Check ; Go check the Y center value
Do_Y_Cen_Dec:
mov bx,NORMAL_CENTER ; Setup normal change value for center
mov cx,NORMAL_CENTER ; Setup normal change value for position
Y_Cen_Dec_Check:
mov ax,cs:[Joy_Y_Center] ; Get the current Y center value
sub ax,bx ; Compute the new Y center value
jc Y_Cen_Dec_Bad ; Jump if Y decrement is bad
cmp ax,MIN_CENTER ; Check against minimum center
jae Y_Cen_Dec_Update ; Go update Y center if in range
Y_Cen_Dec_Bad:
mov ax,MIN_CENTER ; Set Y center to minimum value
Y_Cen_Dec_Update:
mov cs:[Joy_Y_Center],ax ; Update the Y center value
Y_Pos_Dec_Check:
mov ax,cs:[Joy_Y_Pos] ; Get the current Y position value
sub ax,cx ; Compute the new Y position value
jnc Y_Pos_Dec_Update ; Jump if Y position is ok
mov ax,JOY_MIN ; Setup Y position to minimum
Y_Pos_Dec_Update:
mov cs:[Joy_Y_Pos],ax ; Update the Y position value
Y_Cen_Dec_Done:
Restore ax,bx,cx ; Restore the required registers
ret ; Return to the caller
Joy_Y_Cen_Dec Endp ; End of the Joy_Y_Cen_Dec procedure
Subttl Joy_Button_1 Joystick Button 1 Routine
Page +
;******************************************************************************
;
; Joy_Button_1(Scan_Code)
;
; If this is a make code
; Set the button 1 pressed flag
; Else this is a break code
; Reset the button 1 pressed flag
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Button_1 Proc Near ; Joystick button 1 procedure
or ah,ah ; Check for a make or break code
js Button_1_Break ; Jump if this is a break code
Button_1_Make:
or Byte Ptr cs:[Joy_Flag],BUTTON_1_DOWN
jmp Short Button_1_Done ; Go return to the caller
Button_1_Break:
and Byte Ptr cs:[Joy_Flag],Not BUTTON_1_DOWN
Button_1_Done:
ret ; Return to the caller
Joy_Button_1 Endp ; End of the Joy_Button_1 procedure
Subttl Joy_Button_2 Joystick Button 2 Routine
Page +
;******************************************************************************
;
; Joy_Button_2(Scan_Code)
;
; If this is a make code
; Set the button 2 pressed flag
; Else this is a break code
; Reset the button 2 pressed flag
; Endif
; Return to the caller
;
; Registers on Entry:
;
; AH - Original scan code
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joy_Button_2 Proc Near ; Joystick button 2 procedure
or ah,ah ; Check for a make or break code
js Button_2_Break ; Jump if this is a break code
Button_2_Make:
or Byte Ptr cs:[Joy_Flag],BUTTON_2_DOWN
jmp Short Button_2_Done ; Go return to the caller
Button_2_Break:
and Byte Ptr cs:[Joy_Flag],Not BUTTON_2_DOWN
Button_2_Done:
ret ; Return to the caller
Joy_Button_2 Endp ; End of the Joy_Button_2 procedure
Subttl Joystick_Update Joystick Update Routine
Page +
;******************************************************************************
;
; Joystick_Update()
;
; Save the required registers
; If in joystick mode
; If NOT a binary type joystick
; Zero the X position delta value
; Zero the Y position delta value
; If the joystick up is set
; Subtract Y resolution from Y delta value
; Endif
; If the joystick down is set
; Add Y resolution to Y delta value
; Endif
; If the joystick left is set
; Subtract X resolution from X delta value
; Endif
; If the joystick right is set
; Add X resolution to X delta value
; Endif
; Add X delta value to current X position
; Make sure X position is in range
; Add Y delta value to current Y position
; Make sure Y position is in range
; Endif for binary type
; Endif for joystick mode
; Return to the caller
;
; Registers on Entry:
;
; None
;
; Registers on Exit:
;
; None
;
;******************************************************************************
Even ; Force procedure to even address
Joystick_Update Proc Near ; Joystick update procedure
Save ax,bx,cx ; Save the required registers
mov al,cs:[Joy_Status] ; Get the joystick status byte
xor bx,bx ; Zero the X position delta value
xor cx,cx ; Zero the Y position delta value
test cs:[Key_Status],JOY_MODE; Check for keyboard in joystick mode
jz Update_Done ; Jump if NOT in joystick mode
test cs:[Joy_Flag],BINARY_TYPE
jnz Update_Done ; Jump if in binary mode
Up_Test:
test al,UP + UP_LEFT + UP_RIGHT
jz Down_Test ; Jump if NOT moving in up direction
sub cx,cs:[Joy_Y_Res] ; Subtract from Y position delta value
Down_Test:
test al,DOWN + DOWN_LEFT + DOWN_RIGHT
jz Left_Test ; Jump if NOT moving in down direction
add cx,cs:[Joy_Y_Res] ; Add to the Y position delta value
Left_Test:
test al,LEFT + UP_LEFT + DOWN_LEFT
jz Right_Test ; Jump if NOT moving in left direction
sub bx,cs:[Joy_X_Res] ; Subtract from X position delta value
Right_Test:
test al,RIGHT + UP_RIGHT + DOWN_RIGHT
jz Update_X ; Jump if NOT moving in right direction
add bx,cs:[Joy_X_Res] ; Add to the X position delta value
Update_X:
or bx,bx ; Check for a positive/negative value
js Subtract_X ; Jump if X delta value is negative
Add_X:
add bx,cs:[Joy_X_Pos] ; Compute the new X position value
jnc Update_Y ; Jump if X update is ok
X_Update_Bad:
mov bx,JOY_MAX ; Set X position to joystick maximum
jmp Short Update_Y ; Go update the Y position value
Subtract_X:
add bx,cs:[Joy_X_Pos] ; Compute the new X position value
jc Update_Y ; Jump if X update is ok
Bad_X_Update:
mov bx,JOY_MIN ; Set X position to joystick minimum
Update_Y:
or cx,cx ; Check for a positive/negative value
js Subtract_Y ; Jump if Y delta value is negative
Add_Y:
add cx,cs:[Joy_Y_Pos] ; Compute the new Y position value
jnc Update_Position ; Jump if Y update is ok
Y_Update_Bad:
mov cx,JOY_MAX ; Set Y position to joystick maximum
jmp Short Update_Position ; Go update the joystick position
Subtract_Y:
add cx,cs:[Joy_Y_Pos] ; Compute the new Y position value
jc Update_Position ; Jump if Y update is ok
Bad_Y_Update:
mov cx,JOY_MIN ; Set Y position to joystick minimum
Update_Position:
mov cs:[Joy_X_Pos],bx ; Update the joystick X position
mov cs:[Joy_Y_Pos],cx ; Update the joystick Y position
Update_Done:
Restore ax,bx,cx ; Restore the required registers
ret ; Return to the caller
Joystick_Update Endp ; End of the Joystick_Update procedure
;******************************************************************************
;
; Define the joystick status
;
; -----------------
; |7|6|5|4|3|2|1|0|
; -----------------
; | | | | | | | |
; | | | | | | | -------> Joystick up held down
; | | | | | | ---------> Joystick down held down
; | | | | | -----------> Joystick left held down
; | | | | -------------> Joystick right held down
; | | | ---------------> Joystick up/left held down
; | | -----------------> Joystick up/right held down
; | -------------------> Joystick down/left held down
; ---------------------> Joystick down/right held down
;
;******************************************************************************
Joy_Status Db 0 ; Joystick status byte
UP Equ 01h ; Joystick up position flag
DOWN Equ 02h ; Joystick down position flag
LEFT Equ 04h ; Joystick left position flag
RIGHT Equ 08h ; Joystick right position flag
UP_LEFT Equ 10h ; Joystick up/left position flag
UP_RIGHT Equ 20h ; Joystick up/right position flag
DOWN_LEFT Equ 40h ; Joystick down/left position flag
DOWN_RIGHT Equ 80h ; Joystick down/right position flag
;******************************************************************************
;
; Define the joystick flags
;
; -----------------
; |7|6|5|4|3|2|1|0|
; -----------------
; | | | | | | | |
; | | | | | | | -------> Button 1 held down
; | | | | | | ---------> Button 2 held down
; | | | | | -----------> Joystick type (0 = Analog, 1 = Binary)
; | | | | -------------> Joystick center mode (0 = Normal, 1 = Self)
; | | | ---------------> Joystick flight mode (0 = Normal, 1 = Flight)
; | | -----------------> Joystick response mode (0 = Slow, 1 = Fast)
; | -------------------> ***** Reserved *****
; ---------------------> ***** Reserved *****
;
;******************************************************************************
Joy_Flag Db BINARY_TYPE ; Joystick flag byte
BUTTON_1_DOWN Equ 01h ; Joystick button 1 held down flag
BUTTON_2_DOWN Equ 02h ; Joystick button 2 held down flag
BINARY_TYPE Equ 04h ; Joystick binary type flag
SELF_CENTER Equ 08h ; Joystick self center flag
FLIGHT_MODE Equ 10h ; Joystick flight mode flag
FAST_MODE Equ 20h ; Joystick fast mode flag
;******************************************************************************
;
; Define any other joystick variables
;
;******************************************************************************
Joy_X_Pos Dw CENTER_VALUE ; Joystick X axis position value
Joy_Y_Pos Dw CENTER_VALUE ; Joystick Y axis position value
Joy_X_Center Dw CENTER_VALUE ; Joystick X axis center value
Joy_Y_Center Dw CENTER_VALUE ; Joystick Y axis center value
Joy_X_Res Dw START_RES ; Joystick X resolution value
Joy_Y_Res Dw START_RES ; Joystick Y resolution value
Joy_X_Count Db ? ; Joystick X counter value
Joy_Y_Count Db ? ; Joystick Y counter value
;******************************************************************************
;
; Define the end of the Emulator Code Segment
;
;******************************************************************************
Emulate Ends
End ; End of the Joystick module