mirror of
https://github.com/cc65/cc65.git
synced 2024-09-07 09:54:35 +00:00
Up to now static drivers were created via co65 from dynamic drivers. However there was an issue with that approach: The dynamic drivers are "o65 simple files" which obligates that they start with the 'code' segment. However dynamic drivers need to start with the module header - which is written to. For dynamic drivers this isn't more than a conceptual issue because they are always contain a 'data' segment and may therefore only be loaded into writable memory. However when dynamic drivers are converted to static drivers using co65 then that issue becomes a real problem as then the 'code' segment may end up in non-writable memory - and thus writing to the module header fails. Instead of changing the way dynamic drivers work I opted to rather make static driver creation totally independent from dynamic drivers. This allows to place the module header in the 'data' segment (see 'module.mac').
133 lines
3.3 KiB
ArmAsm
133 lines
3.3 KiB
ArmAsm
;
|
|
; Standard joystick driver for the Atari 5200.
|
|
;
|
|
; Christian Groessler, 2014-05-28
|
|
;
|
|
|
|
.include "zeropage.inc"
|
|
|
|
.include "joy-kernel.inc"
|
|
.include "joy-error.inc"
|
|
.include "atari5200.inc"
|
|
|
|
.macpack module
|
|
|
|
|
|
; ------------------------------------------------------------------------
|
|
; Header. Includes jump table
|
|
|
|
module_header _atr5200std_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 $01 ; JOY_UP
|
|
.byte $02 ; JOY_DOWN
|
|
.byte $04 ; JOY_LEFT
|
|
.byte $08 ; JOY_RIGHT
|
|
.byte $10 ; JOY_FIRE
|
|
.byte $20 ; JOY_FIRE2
|
|
.byte $00 ; Future expansion
|
|
.byte $00 ; Future expansion
|
|
|
|
; Jump table.
|
|
|
|
.addr INSTALL
|
|
.addr UNINSTALL
|
|
.addr COUNT
|
|
.addr READJOY
|
|
.addr 0 ; IRQ entry not used
|
|
|
|
.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 #0
|
|
; 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 $FD32 ; check ROM version
|
|
cmp #$E8
|
|
bne @2port
|
|
lda #4
|
|
.byte $2C ; bit opcode, eats the next 2 bytes
|
|
@2port: lda #2
|
|
ldx #0
|
|
rts
|
|
|
|
; ------------------------------------------------------------------------
|
|
; READ: Read a particular joystick passed in A.
|
|
;
|
|
|
|
CENTER = 228 / 2
|
|
SENSIVITY = 16
|
|
|
|
READJOY:
|
|
and #3 ; put joystick number in range, just in case
|
|
tay
|
|
asl a
|
|
tax ; Joystick number * 2 (0-6) into X, index into ZP shadow registers
|
|
|
|
lda #0 ; Initialize return value
|
|
cmp TRIG0,y
|
|
bne @notrg
|
|
lda #$10 ; JOY_FIRE
|
|
|
|
; Read joystick
|
|
|
|
@notrg: ldy PADDL0,x ; get horizontal position
|
|
cpy #CENTER-SENSIVITY
|
|
bcs @chkleft
|
|
|
|
ora #4 ; JOY_LEFT
|
|
bne @updown
|
|
|
|
@chkleft:
|
|
cpy #CENTER+SENSIVITY
|
|
bcc @updown
|
|
|
|
ora #8 ; JOY_RIGHT
|
|
|
|
@updown:ldy PADDL0+1,x ; get vertical position
|
|
cpy #CENTER-SENSIVITY
|
|
bcs @chkdown
|
|
|
|
ora #1 ; JOY_UP
|
|
bne @done
|
|
|
|
@chkdown:
|
|
cpy #CENTER+SENSIVITY
|
|
bcc @done
|
|
|
|
ora #2 ; JOY_DOWN
|
|
|
|
@done: rts
|