mirror of
https://github.com/cc65/cc65.git
synced 2024-11-19 06:31:31 +00:00
6637e28831
remove redundant code and add jmp to the common sequence two more bytes could be saved at the expense of longer sequence with interrupts disabled by moving sei/cli
111 lines
2.4 KiB
ArmAsm
111 lines
2.4 KiB
ArmAsm
;
|
|
; Standard joystick driver for the C64. May be used multiple times when linked
|
|
; to the statically application.
|
|
;
|
|
; Ullrich von Bassewitz, 2002-12-20
|
|
;
|
|
|
|
.include "zeropage.inc"
|
|
|
|
.include "joy-kernel.inc"
|
|
.include "joy-error.inc"
|
|
.include "c64.inc"
|
|
|
|
.macpack generic
|
|
.macpack module
|
|
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Header. Includes jump table
|
|
|
|
module_header _c64_stdjoy_joy
|
|
|
|
; Driver signature
|
|
|
|
.byte $6A, $6F, $79 ; "joy"
|
|
.byte JOY_API_VERSION ; Driver API version number
|
|
|
|
; Library reference
|
|
|
|
.addr $0000
|
|
|
|
; Jump table.
|
|
|
|
.addr INSTALL
|
|
.addr UNINSTALL
|
|
.addr COUNT
|
|
.addr READ
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Constants
|
|
|
|
JOY_COUNT = 2 ; Number of joysticks we support
|
|
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Data.
|
|
|
|
|
|
.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 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: tax ; Joystick number into X
|
|
bne joy2
|
|
|
|
; Read joystick 1
|
|
|
|
joy1: lda #$7F
|
|
sei
|
|
sta CIA1_PRA
|
|
lda CIA1_PRB
|
|
cli
|
|
jmp end
|
|
|
|
; Read joystick 2
|
|
|
|
joy2: ldx #0
|
|
lda #$E0
|
|
ldy #$FF
|
|
sei
|
|
sta CIA1_DDRA
|
|
lda CIA1_PRA
|
|
sty CIA1_DDRA
|
|
cli
|
|
end: and #$1F
|
|
eor #$1F
|
|
rts
|