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cc65/libsrc/c64/c64-ptvjoy.s
cuz 873d9adde9 Use symbolic names instead of numbers
git-svn-id: svn://svn.cc65.org/cc65/trunk@2457 b7a2c559-68d2-44c3-8de9-860c34a00d81
2003-09-28 21:39:20 +00:00

152 lines
3.6 KiB
ArmAsm
Executable File

;
; PTV-4 Player joystick driver for the C64
;
; Groepaz/Hitmen, 2002-12-23
; obviously based on Ullrichs driver :)
;
.include "zeropage.inc"
.include "joy-kernel.inc"
.include "joy-error.inc"
.include "c64.inc"
.macpack generic
; ------------------------------------------------------------------------
; Header. Includes jump table
.segment "JUMPTABLE"
; Driver signature
.byte $6A, $6F, $79 ; "joy"
.byte $00 ; Driver API version number
; Button state masks (8 values)
.byte $01 ; JOY_UP
.byte $02 ; JOY_DOWN
.byte $04 ; JOY_LEFT
.byte $08 ; JOY_RIGHT
.byte $10 ; JOY_FIRE
.byte $00 ; Future expansion
.byte $00 ; Future expansion
.byte $00 ; Future expansion
; Jump table.
.word INSTALL
.word DEINSTALL
.word COUNT
.word READ
; ------------------------------------------------------------------------
; Constants
JOY_COUNT = 4 ; 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 #<JOY_ERR_OK
ldx #>JOY_ERR_OK
; rts ; Run into DEINSTALL instead
; ------------------------------------------------------------------------
; DEINSTALL routine. Is called before the driver is removed from memory.
; Can do cleanup or whatever. Must not return anything.
;
DEINSTALL:
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: tax ; Joystick number into X
bne joy2
; Read joystick 1
joy1: lda #$7F
sei
sta CIA1_PRA
lda CIA1_PRB
cli
and #$1F
eor #$1F
rts
; Read joystick 2
joy2: dex
bne joy3
lda #$E0
ldy #$FF
sei
sta CIA1_DDRA
lda CIA1_PRA
sty CIA1_DDRA
cli
and #$1F
eor #$1F
rts
; Read joystick 3
joy3: dex
bne joy4
lda #%10000000 ; cia 2 port B Data-Direction
sta CIA2_DDRB ; bit 7: out bit 6-0: in
lda #$80 ; cia 2 port B read/write
sta CIA2_PRB ; (output one at PB7)
lda CIA2_PRB ; cia 2 port B read/write
and #$1f ; get bit 4-0 (PB4-PB0)
rts
; Read joystick 4
joy4: lda #%10000000 ; cia 2 port B Data-Direction
sta CIA2_DDRB ; bit 7: out bit 6-0: in
lda #$00 ; cia 2 port B read/write
sta CIA2_PRB ; (output zero at PB7)
lda CIA2_PRB ; cia 2 port B read/write
and #$0f ; get bit 3-0 (PB3-PB0)
sta tmp1 ; joy 4 directions
lda CIA2_PRB ; cia 2 port B read/write
and #%00100000 ; get bit 5 (PB5)
lsr
ora tmp1
ldx #0
rts