-
R registerI'm cross-posting this as a spin-off of a [url="http://www.worldofspectrum.org/forums/discussion/52748/zx-spectrum-cartridges/p2"]thread in "Hardware…
I'm cross-posting this as a spin-off of a [url="http ... programmed, resulting from an LD R, A instruction.
The data ... emulators (the 2 I tested on), increment twice for "LD A,R" instruction ... , and once for all other instructions that I ... -
Z88DK NOOB cplot INK colorHi I am a complete NOOB with Z88DK, I am trying to draw colored circles. How does ink, paper and border work with Z88DK. I started trying to wo…
Hi
I am a complete NOOB with Z88DK, I am trying to ... /> ld a,7
and d
ld b,a
inc b
ld a ... /> }
[/code]
I am compiling with
[code ... -
Basic Screen Shadow QuestionHello, I've been porting a game to the Spectrum from another platform. So far so good and I have per pixel screen scrolling working really nicely …
... />
I've been porting a game to the Spectrum ... with a tilemap setup.
However, I hit a blocker ... or c
ld bc,0x7ffd
ld (0x5b5c),a
out ... [/code]
I'm hoping someone can look ... -
New Game (2016 revival): A Yankee in Iraq (1992)Hello everyone, Way back in 1992, I wrote a shoot-em-up called [i]A Yankee in Iraq[/i]. The entire game was written in Sinclair BASIC. Recently, I…
... 1992, I wrote a shoot-em-up called [i]A Yankee in Iraq[/i]. The ... of my labor, I managed to make a few improvements and ... optimizations. I even figured out how to load a ... the game’s description, a screenshot, and a download link.
... -
Must be missing the point - machine code... Hi Folks, Trying my hand at machine code again but falling at the first hurdle. I hand crafted the following to run at address 62000 and the co…
... at the first hurdle. I hand crafted the following to ... />
[code]
LD A, &FF
LD HL, &4000
RET
[/code]
I have checked the code in ... run the machine crashes. I assume there is something wrong ... -
Why doesnt this work???Simple piece of code wont do as it should, just want to fill the top 22 lines of screen with an attribute value (150) but it wont have any of it. Som…
... the BC register and DJNZ I think.
[code]
ld de,22528
ld bc,704
loop
ld a,150
ld ... (de),a
inc de
Flicker-free animationTrying to create flicker-free screen update, but... Where I'm wrong? [url="https://dl.dropboxusercontent.com/s/pfywhfejfmwt2zq/test_128.sna"]Snaps…
... -free screen update, but... Where I'm wrong?
[url ... />
ld a, (keeper)
rrc a
ld (keeper), a
ld (hl), a
ld a, 0x17
xor %0010
ld (swap_video+1), a
ld bc ...Starting lives for Space Raiders ?:) I was wondering if anyone could point me in the right direction for this please. I've examined the code quite a bit but I'm unable to quite figur…
... 25952[/b] LD (65535), A
[b]25955[/b] LD (65330), A
... LD A, (24611)
[b]25962[/b] DEC A ;[i] < Lose a life ...
[b]25963[/b] LD (24611), A
I have a feeling with this the answer ...Fast way to clear the screen ?So I was wondering fastest way to clear the screen. I've tried this and this works but is it better than CLS ? LD HL,16384 LD BC, 6144 Loop…
... clear the screen.
I've tried this and this ... /> LD HL,16384
LD BC, 6144
Loop:
LD A,0 ...
LD (HL),A
INC HL
DEC BC
LD A ... flickering my guess is that I still have to use double ...Random Numbers, USR Return Values & Timing BASICI've been trying out Jon Ritman's random number routine, published in Your Sinclair Aug'87. Apart from a timing comparison I also did a frequency ana…
... Apart from a timing comparison I also did a frequency analysis across ... this:
[code]
LD bc,(SEED)
call $2d2b ... ,$38 ;restack,end_calc
LD A,(HL) ;Fetch the exponent of ... exponent, i.e. divide 'last value'
LD (HL),A ;by ...HELP!I'm trying to replace a bit in a byte as follows, but having some sort of brain freeze trying to get it to do what I want. A=00 if bit to replace …
... to do what I want.
A=00 if bit ...
E=bit (i.e. 80h,40h,20h,10h ... is clear?!
I was hoping to achieve this ... proving tricky.
I've tried all sorts of ...
XOR (HL)
LD (HL),A
nearly does ...Scrolling loader counter in 85 T-States?Would it be possible to write a scrolling loader counter in 85 T-States? I have a custom screen load routine that loads attribute first, then the …
... -States?
I have a custom screen load routine that ... />
I'm only using a and IX registers, I've timed ... $82 ; 07ts
ld ixh, a ; 08ts
ld a, nextpix-aa2sa ; 07ts ; ... be good if I can fudge in a scrolling load counter ...New Game: A Yankee in Iraq (2017). A shoot-em-up.Last year, I [url="https://www.worldofspectrum.org/forums/discussion/53207/new-game-2016-revival-a-yankee-in-iraq-1992"]resurrected my old shoot-em-u…
... 53207/new-game-2016-revival-a-yankee-in-iraq-1992"]resurrected ... stay true to the original (i.e. simple graphics and straightforward ... fun to play (homing missiles, a faux parallax effect, to name ... path.com/zx/25_years_in_the_making.html"][i]A Yankee in Iraq (2017 ...ZXSCLZF - Yet another Screen CompressorQuick disclaimer before I continue, this compressor does not shrink screens as small as some of the others posted here, in particular the very good z…
... make it optimal as I haven't a clue!
}
i-=2; //move to next option ... br /> _YSIZE=atoi(*++argv);
i-=5;
} else {
_ulzfa040:
ld a,(hl) ; 7t
ld (de),a ; 7t
...Mojon Twins MK2 and lighting effectsDoes anyone have any experience in getting the overlay.h working in the MK2 engine. There were several games written in the churro that used the ove…
... in the Tenebra Macabre game. I cannot get this to work ... problem arises that every time I include overlay.h, and compile ...
ld a, (_ovl_y)
ld h, 0
ld l, a
add ...High score table routineI wrote this general purpose high score table routine. It stores 5 scores and displays them alongside the player names, which are 8 characters long. …
I wrote this general purpose high ... job and I wrote it from scratch - with just a small portion ... when taking into account that I started writing my own assembly ... /> INSER:
LD A,8
LD (FLAG2),A ; Caps Lock
Flood Fill IssueHi Folks, Came across the following Flood Fill routine by John Metcalf: [code]; scanline fill by John Metcalf ; call with d=x-coord, e=y-coo…
... /> inc a 60010 3C
ld b,a 60011 47
ld a,1 60012 ... AB
ld h,a 60072 67
ld a,l 60073 7D ... 0F
ld l,a 60081 6F
ld a,b 60082 78 ... br />
Thought I would give it a go and entered it ...1k Chess (was the 924 bytes thing!)Hi, I've decided to do a major rewrite of large parts of the code for the isometric Chess thing that I've been messing with. It got to the point, …
... stuck on a key feature, which though I have working, I'm certain ... work fine, if a little slow, I'm just convinced it ... /> rl (hl)
sbc a,a
ld (de),a
inc e
Need help from people with a 48K/128K/+2 (not +2A/+3)Scared ya, didn’t I? Well, this one is very simple and not as involved as [url="https://www.worldofspectrum.org/forums/discussion/55142/need-help-fro…
... bag of horrors[/url]. I’m pretty sure the ... no unpleasant surprises, so I’m asking for feedback ... of [i]A Yankee in Iraq[/i] and play it for a few ...
You’ll see a yellow border stripe around the ... It may flicker occasionally when a sound is played, but ...Reviving a Konix Navigator joystickAaaaaaaaaaaand my next bit of required advice comes courtesy of another eBay package I've just received in the post this morning - with a Spectrum +3…
... !* across the room where I only get a vague idea of where ... landed. I may have taught the kids next door a few very ... will most likely be a complete disassembly, so I'll have all ... , but I had to go on... [i]a Bread Bin forum![/i] where I found ...No-tearing (“vsync”) Full Screen FadeSeeing as most screen fades exhibit visible tearing, I wrote my own routine which does away with that problem. Simple, effective, short, and fully re…
... screen fades exhibit visible tearing, I wrote my own routine which ... active screen area,
ld a,d ;plus generous overlap to ... />
fade1 ld a,(hl) ;read attr into A
and 7 ... decrement INK
f1 ld a,(hl) ;reload A with attr
and ...How to avoid flicking? IM2 help.Hi, I have started on a quest to make a demo for ZX Spectrum. However the display is flickering and I guess it is something about updating at…
... />
I have started on a quest to make a demo for ... time.
I have read something about IM2 ... flicking problem.
I hope someone give me ... ld a,(pattern1)
ld bc,three_lines
ld (hl),a
ldir
ld a ...Prportional Ascii text scrollerA couple of years ago I wrote a little scroller that nestles at the top of RAM (FFCA - 65482) and scrolls standard Ascii encoded text from anywhere y…
... 04h,42h,4ch,70h,0c0h ;I
db 04h,4ah,5ch ... ,9ch ;h
db 0dch ;i
db 01h,0deh ;j ... text stream character addr.
ld a,(de)
sub 20h ;test ...Printing text, part MMXIIXI'm pretty sure there's been a zillion threads about this already, and I don't think it's the first one by myself either, but here goes. Proportiona…
... pixel in height. I started from a function compiled with ... SDCC and I've spent a couple evenings optimizing ... />
Things I'm aware of:
- I could align tables ... ld a,b
add a,a
add a,a
add a,a
add a,a
ld ...Printing text using direct screen addressingHaving some problems printing using the FASE engine which is currently defeating me. Hoping to have someone clear out the bit of fog currently dwell…
... my brain for this function. I'm trying to get the ...predetermined number of loops in assemblerhi, i have this code that i have already written org 40000 ld c,33 ld (23612),a ld a,c rst 16 inc c jp 40001 but i only want to loop i…
hi,
i have this code that i have already written
ld c,33
ld (23612),a
ld a,c
rst ... /> jp 40001
but i only want to loop it ... times. how do i do this? i have had a look round the ...counting in assembleri have this program which cycles through the character set. how do i do this with numbers say 0 to 65535? org 40000 ld b,120 ld (23612),a L…
i have this program which cycles ... the character set. how do i do this with numbers say ... 40000
ld b,120
ld (23612),a
LD A,2
CALL ... /> LD a,00
RST 16
LD a,00
RST 16
ld a ...
