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What Spectrum projects (Software/Games/Utility)(Hardware)(Others) are you working on?So, basically that :) You dont have to give names or more clues if you dont want to ;) Also, if you are working on more than one, you can tell all of…
... /> ; enter : hl = void *s
; e = char c
; bc = uint ... />
ld a,e
ld e,l
ld d,h
Math Quiz - MultiplicationThe topic is fast multiplication routines, from 8x8 to 32x32 and all points in between. These functions sit underneath floating point libraries, gen…
... /> ld h, 0
ld l, e
IF data != 1 & ... ;& data != 128
ld d, h
ENDIF
multsub ...that "listing variables during runtime" thingWell, I did eventually finish this, but with my meds playing up I don't have much time each day that I can spend at the computer, so it's taken rathe…
... ";: LET d=PEEK i:
IF d=cd THEN ... LET f=i
9903 LET e=INT (d ... /32): LET l$=CHR$ (d-e*32+96): PRINT l$;
9904 IF e ... =2 OR e ... =4 OR e ...Column and row numbers to attr address?[FONT=Calibri][SIZE=3]Can anyone provide me with a code snippet the will convert the column and row numbers into the screen attribute address. For ex…
[CODE] ld a,e
add a,a
... ,22528/4
or l
ld l,a
add hl ...
ld a,l
or d
ld l,a[/CODE]
Column and row numbers to attr address?[FONT=Calibri][SIZE=3]Can anyone provide me with a code snippet the will convert the column and row numbers into the screen attribute address. For ex…
... +E*32+D
Quick, dirty and untested code:
Input: D ... =column, E=row
Output: HL ... ]ld h,0
ld l,d
add hl,hl
ld e,d
ld d,58h
add hl ...Column and row numbers to attr address?[FONT=Calibri][SIZE=3]Can anyone provide me with a code snippet the will convert the column and row numbers into the screen attribute address. For ex…
... =evilpaul;766654][CODE] ld a,e
add a,a
or l
ld l,a
add hl ...
ld a,l
or d
ld l,a[/CODE]Answer ...Sorting BusinessThis is a little bit different from the usual game-related fare but I know there are a few people here who like this sort of thing. This is about so…
... br />
ld l,e
ld h,d
add ...
ld a,l
cp e
jr nz, begin_loop ... br />
ld l,e
ld h,d
or ... br />
ld e,l
ld d,h ; de = j-1 ...Optimal shifting for set pixel?Hi, I'm optimizing my set pixel code. For speed. But without using partitioned memory (i.e. a table on 256 byte boundary) I have optimal memory addr…
... PLOTTBL,L,D,B,(HL):INC H
LD A,(HL),L,E:INC ... LD DE,#4000,BC,#8000,L,E
FLP1 LD H,high ...
LD (HL),D:INC H:LD (HL),E:INC H
E,A:JR C,FNXT
LD A,D:SUB 8:LD D ... ,A
FNXT INC L:JR NZ ...So shooting 360 degrees?...[I]How do I go about having - for example - a cannon in the middle of the screen, that can shoot in any direction towards the player?[/I] Well, I do…
... ,D keep whole part of number while L,E keep fractional part i.e ...Help needed with calculating screen addressesCan anyone help me finally crack Jonathan Cauldwell's screen addressing calculator and, more to the point, is the reason I'm struggling because this …
Provided the Pixel Address Table is aligned to an even byte ($00, $02 etc) then 2 t-states can be saved thus, correct?
[CODE]LD E,(HL)
INC HL change to INC L
LD D,(HL)[/CODE]Help needed with calculating screen addressesCan anyone help me finally crack Jonathan Cauldwell's screen addressing calculator and, more to the point, is the reason I'm struggling because this …
Provided the Pixel Address Table is aligned to an even byte ($00, $02 etc) then 2 t-states can be saved thus, correct?
[CODE]
LD E,(HL)
INC HL change to INC L
LD D,(HL)[/CODE]Best text adventure?I'm looking to revisit a text adventure, and I was curious what people would recommend as one of the best text adventure games on the Spectrum. Not …
... adventure scene. If so I'd probably suggest the more simple ... /> Back in the day I'd probably go for those complex ... usually means huge vocabulary, i.e. more guessing), mazes (i just ... for something simple like Red Door (you'd need to be good ...clear a windowed area of the screenHi everyone! Ain't been on here for donkeys, but have recently started messing around with a little game. I'm looking for ideas/opinions on the bes…
... /> PUSH HL
LD E,L
LD D,H
INC DE ... /> RET NZ
LD A,L
ADD A,20H
LD L,A
RET C
64x48 monochrome big pixels display ideaHi. I was playing with this idea of having a simple 64x48 bytes buffer, 1 byte per pixel, then a renderer which would take that buffer and render it…
... /> ld (hl),a
inc l
OR
ld (hl),a ; a/b/e/d
inc h
ld ... /> ld (hl),a
inc l
ret ;->
Testers for new z88dk clibA long (long, long, long) time ago a few people offered to help test the new clib in z88dk. Much time has passed since then and I won't hold people,…
... /> ld d,(hl)
ld e,+0x00
ld l, d
... br /> ld d,(hl)
ld l, e
ld h, d
... ,a
ld l, e
ld h, d
inc hl ... :103:
ld l, e
ld h, d
ld a, ... :106: }
ld l, e
ld h, d
ld a, ...Arcade Game DesignerTime I posted an update on this, I've been working on the next version - along with another developer who is writing the editors - since July. Wor…
... for such games?
It'd be nice to be able ... block" instruction would be great ( l.e. if you hit a certain ...Small Machine Code Routines Which Maybe UsefulAs part of creating Flynn's Adventure in Bombland I created a lot of little routines to do all sorts of things. A lot of these I created based on inp…
... /> call print_halfchar
dec d
call screen2att
rowdown:
ld a,e
add a,32
or l
ld e,a
ld ... /> ld h,a
ld l,e
ret
;
d,h
ld e,1
ld (hl),l
Spectrum Screen RAM layoutHi there The spectrum screen layout is rather odd. It seems to be arranged into 3 256 byte groups. If I have an x (horizontal) coordinate (from…
... and 7
or d
ld d,a
ld a ... screen
inc d
ld a,d
and 7 ... ret c
ld a,d
sub 8
ld ... at ATTRS
ld a,d
rra
rra ... /> ld h,a
ld l,e
ret
;
[/ ...z88dk v1.99A Release Candidate[b]Z88DK VERSION 1.99A RELEASE CANDIDATE[/b] Download from: http://nightly.z88dk.org/Releases/ The release candidate will be available for te…
... /> [code]
__DPROTO(`d,e',`d,e',size_t,,strlen,char *s)
ld c,l
ld b,h ... push bc
ld l, e
call _strlen_fastcall
ld l, c
call _strlen_fastcall ...ZX Spectrum CartridgesI have been thinking of "cloning" ZX Cartridges for a while (case, board and silicon skirt), to be able to make new releases or replace damaged cartr…
... E ; Save command param
LD HL, ADDR
LD E,L ...
LD D,H
...
[code];InputParams: A = Command, [E = Command Param], BC = Addr
LD E,L
LD D,H
...Optimized (in size) Z80 simulatorI am evaluating Z80 simulators to try to create a tool to analyse z80 programs. I'd like to start with a simple register coverage tool and t-state cy…
... register B with alternate register E in this part of code ... optimize them i.e. LD A,10...LD D,A...PUSH DE ... ...POP HL is LD H,10, LD L,E ...Proportional fontsI've been doing some proportional font drawing, purely on C level at the moment, but it's orders of magnitude slower than I'd want it to be. It's sti…
... />
pop de
ld l,e ;H = MSB of font data ... /> ld a,(hl)
ld l,d
xor (hl)
and ...A sped up pixel-shift routine for 1-byte–wide spritesHere’s an optimized (for speed) real-time sprite shifting routine for sprites that are one byte wide. It uses no memory variables for storage of inte…
...
ld e,(hl)
inc l
ld d,0
ex ... )
xor d
ld (hl),a
inc l
ld ... a,(hl)
xor e
ld ...A sped up pixel-shift routine for 1-byte–wide spritesHere’s an optimized (for speed) real-time sprite shifting routine for sprites that are one byte wide. It uses no memory variables for storage of inte…
...
ld e,(hl)
inc l
ld d,0
ex ... )
xor d
ld (hl),a
inc l
ld ... a,(hl)
xor e
ld ...Look whats possible in 924 bytesSo, finally after over a year of development and nearly 25 years since I first designed the graphics, I've actually made it to the point where this i…
... C WITH CONTENTS OF D
BIT 7,L ;IN HERE, WE ... ABSOLUTELY NEED BIT 7 OF L.
LD D,E ... ;LOAD D WITH CONTENTS OF E
L1 ...
