dos33fsprogs/mist/qload.s
Vince Weaver b1baf474aa mist: fix bugs with save games on real hardware
didn't trigger on cffa3k or emulator

first was I was accidentally forcing slot 6

the other was the timing-sensitive write routine was straddling
a page boundary, leading to the cycle-counted write code taking
the wrong number of cycles
2020-09-06 17:17:12 -04:00

247 lines
4.7 KiB
ArmAsm

; Loader for MIST
.include "zp.inc"
.include "hardware.inc"
.include "common_defines.inc"
.include "qboot.inc"
qload_start:
; init the write code
lda WHICH_SLOT
jsr popwr_init
; first time entry
; start by loading text title
lda #LOAD_TEXT_TITLE ; load title
sta WHICH_LOAD
lda #1
sta CURRENT_DISK ; current disk number
jsr load_file
jsr $800
lda #LOAD_TITLE ; load title
sta WHICH_LOAD
main_game_loop:
jsr load_file
lda WHICH_LOAD
bne not_title
start_title:
jsr $4000
jmp main_game_loop
not_title:
jsr $2000
jmp main_game_loop
;====================================
; loads file specified by WHICH_LOAD
;====================================
load_file:
ldx WHICH_LOAD
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
rts
;===================================================
;===================================================
; change disk
;===================================================
;===================================================
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
; offset 59
; disk1 = $0a
; disk2 = $32 ('2')
; disk3 = $33 ('3')
lda $c59
cmp #$0a
beq is_disk1
cmp #$32
beq is_disk2
cmp #$33
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
which_disk_array:
.byte 1,1,3,3 ; MIST_TITLE,MIST,MECHE,SELENA
.byte 1,1,3,2 ; OCTAGON,VIEWER,STONEY,CHANNEL
.byte 2,1,2,2 ; CABIN,DENTIST,ARBOR,NIBEL
.byte 1,1,1,3 ; SHIP,GENERATOR,D'NI,SUB
.byte 1 ; TEXT_TITLE
.byte 1,1,1,1,1 ; SAVE1,SAVE2,SAVE3,SAVE4,SAVE5
.byte $f ; FIRST_SECTOR
load_address_array:
.byte $40,$20,$20,$20 ; MIST_TITLE,MIST,MECHE,SELENA
.byte $20,$20,$20,$20 ; OCTAGON,VIEWER,STONEY,CHANNEL
.byte $20,$20,$20,$20 ; CABIN,DENTIST,ARBOR,NIBEL
.byte $20,$20,$20,$20 ; SHIP,GENERATOR,D'NI,SUB
.byte $08 ; TEXT_TITLE
.byte $0E,$0E,$0E,$0E
.byte $0E ; SAVE1,SAVE2,SAVE3,SAVE4,SAVE5
.byte $0C ; FIRST_SECTOR
track_array:
.byte 2, 8, 1,21 ; MIST_TITLE,MIST,MECHE,SELENA
.byte 18,31,11, 1 ; OCTAGON,VIEWER,STONEY,CHANNEL
.byte 27,26,10,20 ; CABIN,DENTIST,ARBOR,NIBEL
.byte 30,32,28,30 ; SHIP,GENERATOR,D'NI,SUB
.byte 0 ; TEXT_TITLE
.byte 0, 0, 0, 0, 0 ; SAVE1,SAVE2,SAVE3,SAVE4,SAVE5
.byte 0 ; FIRST_SECTOR
sector_array:
.byte 0, 0, 0, 0 ; MIST_TITLE,MIST,MECHE,SELENA
.byte 0, 8, 0, 0 ; OCTAGON,VIEWER,STONEY,CHANNEL
.byte 0, 0, 0, 0 ; CABIN,DENTIST,ARBOR,NIBEL
.byte 0,12, 0, 1 ; SHIP,GENERATOR,D'NI,SUB
.byte 6 ; TEXT_TITLE
.byte 11,12,13,14,15 ; SAVE1,SAVE2,SAVE3,SAVE4,SAVE5
.byte 0 ; FIRST_SECTOR
length_array:
.byte 83,159,157,145 ; MIST_TITLE,MIST,MECHE,SELENA
.byte 128, 19,158,135 ; OCTAGON,VIEWER,STONEY,CHANNEL
.byte 61, 31,159,109 ; CABIN,DENTIST,ARBOR,NIBEL
.byte 20, 33, 27, 78 ; SHIP,GENERATOR,D'NI,SUB
.byte 3 ; TEXT_TITLE
.byte 1,1,1,1,1 ; SAVE1,SAVE2,SAVE3,SAVE4,SAVE5
.byte 1 ; FIRST_SECTOR
.include "audio.s"
.include "linking_noise.s"
.include "decompress_fast_v2.s"
.include "draw_pointer.s"
.include "end_level.s"
.include "gr_copy.s"
.include "gr_fast_clear.s"
.include "gr_offsets.s"
.include "gr_pageflip.s"
.include "gr_putsprite_crop.s"
.include "keyboard.s"
.include "text_print.s"
.include "loadstore.s"
.include "joystick.s"
.include "page_sprites.inc"
.include "common_sprites.inc"
.include "qkumba_popwr.s"
qload_end:
.assert (>qload_end - >qload_start) < $e , error, "loader too big"