a2d/desktop/ovl1a.s
2018-11-21 20:24:30 -08:00

145 lines
3.3 KiB
ArmAsm

;;; ============================================================
;;; Overlay for Disk Copy - $1800 - $19FF (file 2/4)
;;; ============================================================
.proc disk_copy_overlay2
.org $1800
jmp start
;;; ============================================================
DEFINE_OPEN_PARAMS open_params, filename, $1C00
filename: PASCAL_STRING "DeskTop2"
DEFINE_READ_PARAMS read_params, 0, 0
DEFINE_SET_MARK_PARAMS set_mark_params, $133E0
DEFINE_CLOSE_PARAMS close_params
.byte $00,$00
buf1: .addr $4000
dest1: .addr $D000
len1: .word $2200
buf2: .addr $800
len2: .word $B00
;;; ============================================================
start: lda #$41 ; ???
sta RAMWRTON
sta $0100
sta $0101
sta RAMWRTOFF
;; Free up system bitmap
ldx #BITMAP_SIZE-3
lda #0
L183F: sta BITMAP+1,x
dex
bpl L183F
yax_call MLI_RELAY, OPEN, open_params
lda open_params::ref_num
sta read_params::ref_num
sta set_mark_params::ref_num
yax_call MLI_RELAY, SET_MARK, set_mark_params
copy16 buf1, read_params::data_buffer
copy16 len1, read_params::request_count
yax_call MLI_RELAY, READ, read_params
jsr copy_to_lc
copy16 buf2, read_params::data_buffer
copy16 len2, read_params::request_count
yax_call MLI_RELAY, READ, read_params
yax_call MLI_RELAY, CLOSE, close_params
sta ALTZPON
lda LCBANK1
lda LCBANK1
jmp MGTK_RELAY
;;; ============================================================
;;; Copy first chunk to the Language Card
.proc copy_to_lc
src := $6
end := $8
dst := $A
;; Bank in AUX LC
sta ALTZPON
lda LCBANK1
lda LCBANK1
txa
asl a
tax
;; Set up pointers
lda buf1
sta src
clc
adc len1
sta end
lda buf1+1
sta src+1
adc len1+1
sta end+1
lda dest1
sta dst
lda dest1+1
sta dst+1
;; Do the copy
ldy #0
loop: lda (src),y
sta (dst),y
inc src
inc dst
lda src
bne :+
inc src+1
inc dst+1
: lda src+1
cmp end+1
bne loop
lda src
cmp end
bne loop
;; Bank in ROM
sta ALTZPOFF
lda ROMIN2
rts
.endproc
;;; ============================================================
.proc MLI_RELAY
sty call
stax params
php
sei
jsr MLI
call: .byte 0
params: .addr 0
plp
and #$FF
self: bne self ; hang if fails
rts
.endproc
;;; ============================================================
;;; Padded with a chunk of BASIC.SYSTEM 1.1
;;; (Loaded at: $A721 - $A7FF; file offset $1120)
.incbin "inc/bs.dat"
;;; ============================================================
PAD_TO $1A00
.endproc ; disk_copy_overlay2