uzix/pacemuzx
1
0
Fork 0
mirror of https://github.com/UzixLS/pacemuzx.git synced 2025-07-18 23:01:36 +03:00
Code Issues Projects Releases Wiki Activity

Added Spectranet support

Browse Source 
We now check for Spectranet execution traps being enabled.  If found we prompt the user to disable them, and wait until that has been done before we continue.
This commit is contained in:
Simon Owen
2011-12-05 17:33:06 +00:00
parent 108a13816c
commit 348d5c2caa
1 changed files with 66 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

81
pacemuzx.asm
View File

@ -94,8 +94,8 @@ dip_5040: defb %11111111 ; c--sdrlu c=cocktail/upright ; s=servic
dip_5080: defb %11001001 ; -dbbllcc d=hard/normal bb=bonus life at 10K/15K/20K/none ; ll=1/2/3/5 lives ; cc=freeplay/1coin1credit/1coin2credits/2coins1credit
; default: normal, bonus life at 10K, 3 lives, 1 coin 1 credit
; First, check that +2A/+3 paging is available
start2: di
ld a,(&5b5c) ; sysvar holding 128K paging
ex af,af' ; keep safe
ld a,%00000001 ; special paging, banks 0/1/2/3
@ -106,22 +106,11 @@ start2: di
jr z,start3 ; if so, start up
ex af,af'
call &0d6b ; CLS
ld a,2 ; main screen
call &1601 ; CHAN-OPEN
out (c),a ; restore 128K paging (disturbed due to partial address decoding)
ei
ld hl,fail_msg
msg_lp: ld a,(hl)
and a
ret z
rst 16 ; PRINT-A
inc l
jr msg_lp
fail_msg: defm "This program requires a +2A/+3"
defb 0
ld hl,plus2a3_msg
jp print_msg
; Next, move any data from load position to final location
start3: ld sp,new_stack
@ -140,6 +129,23 @@ start3: ld sp,new_stack
ld bc,&1ffd
out (c),a ; restore R3/5/2/0, for ROM access at &c000
call chk_specnet ; check if Spectranet traps are enabled
jr z,no_specnet ; skip forwards if not
ld hl,specnet_msg ; prompt to disable traps
call print_msg
wait_specnet: ld bc,0 ; delay roughly half a second
delay: djnz $
djnz $
dec c
jr nz,delay
call chk_specnet ; check traps again
jr nz,wait_specnet ; jump back if they're still enabled
no_specnet:
ld a,%10000011 ; DivIDE page 3
out (divide),a ; page in at &2000, if present
@ -2358,10 +2364,55 @@ blockdown_de: ld a,e
ld d,a
ret
defs (-$)%256 ; align to next 256-byte boundary
; Check that Spectranet traps are disabled, if one is connected
chk_specnet: ld hl,&3ff9 ; PAGEIN
ld a,(hl) ; save currently paged value at trap
push af
push hl
ld hl,&4000 ; first byte in (display) RAM after trap
ld c,(hl) ; save current value
ld (hl),&c9 ; RET
call &3ff9 ; attempt page-in
ld (hl),c ; restore display byte
pop hl
pop af
cp (hl) ; did the paging change?
ret z ; return Z if not (no Spectranet or traps disabled)
jp &007c ; exit via RET in Speccy ROM to page out
; Display a message using the ROM routines
; String in HL (null-terminated), paging expected to be correct
;
print_msg: push hl
call &0d6b ; CLS
ld a,2 ; main screen
call &1601 ; CHAN-OPEN
pop hl
msg_lp: ld a,(hl)
and a
ret z
rst 16 ; PRINT-A
inc l
jr msg_lp
specnet_msg: defm "Disable Spectranet traps now..."
defb 0
plus2a3_msg: defm "This program requires a +2A/+3"
defb 0
defs (-$)%256 ; align to next 256-byte boundary
; Scan a 32-byte block for changes, used for fast scanning of the Pac-Man display
; Aligned on a 256-byte boundary for easy resuming of the scanning
;
find_change: ld a,(de) ; 0
cp (hl)
ret nz