dos33fsprogs/demos/outline2021/demo/qload.s
2021-05-10 18:24:49 -04:00

174 lines
2.4 KiB
ArmAsm

; Loader for ootw
;.include "../zp.inc"
;.include "../hardware.inc"
;.include "common_defines.inc"
.include "qboot.inc"
qload_start:
jsr load_file
; always enter at $5000
jmp $5000
;====================================
; loads file specified by WHICH_LOAD
;====================================
load_file:
ldx #0
; lda which_disk_array,X
; cmp CURRENT_DISK
; bne change_disk
load_file_no_diskcheck:
lda load_address_array,X
sta load_address
lda track_array,X
sta load_track
lda sector_array,X
sta load_sector
lda length_array,X
sta load_length
jsr load_new ; FIXME: tail call
rts
;===================================================
;===================================================
; change disk
;===================================================
;===================================================
.if 0
change_disk:
; turn off disk drive light
jsr driveoff
jsr TEXT
jsr HOME
lda #<error_string
sta OUTL
lda #>error_string
sta OUTH
ldx WHICH_LOAD
lda which_disk_array,X
clc
adc #48
ldy #19
sta (OUTL),Y
ldy #0
quick_print:
lda (OUTL),Y
beq quick_print_done
jsr COUT1
iny
jmp quick_print
quick_print_done:
fnf_keypress:
lda KEYPRESS
bpl fnf_keypress
bit KEYRESET
;==============================================
; actually verify proper disk is there
; read T0:S0 and verify proper disk
lda WHICH_LOAD
pha
ldx #LOAD_FIRST_SECTOR ; load track 0 sector 0
stx WHICH_LOAD
jsr load_file_no_diskcheck
pla
sta WHICH_LOAD
tax
; first sector now in $c00
; disk1 = $01
; disk2 = $02
; disk3 = $03
lda $ca5
cmp #$01
beq is_disk1
cmp #$02
beq is_disk2
cmp #$03
beq is_disk3
bne change_disk ; unknown disk
is_disk1:
lda #1
bne disk_compare
is_disk2:
lda #2
bne disk_compare
is_disk3:
lda #3
disk_compare:
cmp which_disk_array,X
bne change_disk ; disk mismatch
;==============================================
; all good, retry original load
jsr HOME
ldx WHICH_LOAD
lda which_disk_array,X
sta CURRENT_DISK
jmp load_file
; offset for disk number is 19
error_string:
.byte "PLEASE INSERT DISK 1, PRESS RETURN",0
.endif
which_disk_array:
.byte 1,1,1,1 ;
load_address_array:
.byte $50 ;
track_array:
.byte 2 ;
sector_array:
.byte 0 ;
length_array:
.byte 112 ;
; include common libraries...
qload_end:
.assert (>qload_end - >qload_start) < $e , error, "loader too big"