mirror of
https://github.com/cc65/cc65.git
synced 2024-11-04 02:05:13 +00:00
147 lines
3.8 KiB
ArmAsm
147 lines
3.8 KiB
ArmAsm
;
|
|
; IJK joystick driver for the Atmos
|
|
; Can be used multiple times when statically linked to the application.
|
|
;
|
|
; 2002-12-20, Based on Ullrich von Bassewitz's code.
|
|
; 2017-11-01, Stefan Haubenthal
|
|
;
|
|
|
|
.include "joy-kernel.inc"
|
|
.include "joy-error.inc"
|
|
.include "atmos.inc"
|
|
|
|
.macpack module
|
|
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Header. Includes jump table
|
|
|
|
module_header _atmos_ijk_joy
|
|
|
|
; Driver signature
|
|
|
|
.byte $6A, $6F, $79 ; "joy"
|
|
.byte JOY_API_VERSION ; Driver API version number
|
|
|
|
; Library reference
|
|
|
|
.addr $0000
|
|
|
|
; Button state masks (8 values)
|
|
|
|
.byte $10 ; JOY_UP
|
|
.byte $08 ; JOY_DOWN
|
|
.byte $01 ; JOY_LEFT
|
|
.byte $02 ; JOY_RIGHT
|
|
.byte $20 ; JOY_FIRE
|
|
.byte $00 ; Future expansion
|
|
.byte $00 ; Future expansion
|
|
.byte $00 ; Future expansion
|
|
|
|
; Jump table.
|
|
|
|
.addr INSTALL
|
|
.addr UNINSTALL
|
|
.addr COUNT
|
|
.addr READ
|
|
.addr 0 ; IRQ entry unused
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Constants
|
|
|
|
JOY_COUNT = 2 ; Number of joysticks we support
|
|
|
|
.code
|
|
|
|
; ------------------------------------------------------------------------
|
|
; INSTALL routine. Is called after the driver is loaded into memory. If
|
|
; possible, check if the hardware is present and determine the amount of
|
|
; memory available.
|
|
; Must return an JOY_ERR_xx code in a/x.
|
|
;
|
|
|
|
INSTALL:
|
|
lda #%11000000
|
|
sta VIA::DDRA
|
|
sta VIA::PRA
|
|
lda VIA::PRA
|
|
and #%00100000
|
|
bne ijkPresent
|
|
lda #<JOY_ERR_NO_DEVICE
|
|
.byte $2C ; Skip next opcode
|
|
ijkPresent:
|
|
lda #<JOY_ERR_OK
|
|
ldx #>JOY_ERR_OK
|
|
; rts ; Run into UNINSTALL instead
|
|
|
|
; ------------------------------------------------------------------------
|
|
; UNINSTALL routine. Is called before the driver is removed from memory.
|
|
; Can do cleanup or whatever. Must not return anything.
|
|
;
|
|
|
|
UNINSTALL:
|
|
rts
|
|
|
|
|
|
; ------------------------------------------------------------------------
|
|
; COUNT: Return the total number of available joysticks in a/x.
|
|
;
|
|
|
|
COUNT:
|
|
lda #<JOY_COUNT
|
|
ldx #>JOY_COUNT
|
|
rts
|
|
|
|
; ------------------------------------------------------------------------
|
|
; READ: Read a particular joystick passed in A.
|
|
;
|
|
|
|
READ:
|
|
bne right
|
|
|
|
; Ensure Printer Strobe is set to Output
|
|
lda #%10110111
|
|
sta VIA::DDRB
|
|
; Set Strobe Low
|
|
lda #%00000000
|
|
sta VIA::PRB
|
|
; Set Top two bits of PortA to Output and rest as Input
|
|
lda #%11000000
|
|
sta VIA::DDRA
|
|
|
|
; Select Left Joystick
|
|
lda #%01111111
|
|
sta VIA::PRA
|
|
; Read back Left Joystick state
|
|
lda VIA::PRA
|
|
; Mask out unused bits
|
|
and #%00011111
|
|
; Invert Bits
|
|
eor #%00011111
|
|
; Index table to conform to Generic Format
|
|
tax
|
|
lda GenericIJKBits,X
|
|
bne L1
|
|
|
|
right:
|
|
; Select Right Joystick
|
|
lda #%10111111
|
|
sta VIA::PRA
|
|
; Read back Right Joystick state and rejig bits
|
|
lda VIA::PRA
|
|
and #%00011111
|
|
eor #%00011111
|
|
tax
|
|
lda GenericIJKBits,X
|
|
|
|
; Restore VIA PortA state
|
|
L1: ldx #%11111111
|
|
stx VIA::DDRA
|
|
inx ; x=0
|
|
rts
|
|
|
|
.rodata
|
|
GenericIJKBits:
|
|
.byte 0,2,1,3,32,34,33,0,8,10,9,0,40,42,41,0
|
|
.byte 16,18,17,0,48,50,49,0,0,0,0,0,0,0,0,0
|