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How can I tell if 128k in codeIs there an easy way in code to check if the Spectrum has 128k, rather than 48k so I can display a message "Must have 128k" etc
... ).
I have a program written by Vision ... "SpecTest", which runs a couple quick tests and ... paging. Page in a RAM page, write a byte to 49152, ... page in another RAM page, write a different byte ... in and test the byte. The value will tell ... -
Lesser used BASIC commandsAre there any interesting articles or books that explore some of the lesser used BASIC commands/functions e.g. DEF FN, IN, OUT etc? The Spectrum BAS…
... />
Description
This reads a byte from the specified location in ... bottom three bits of the byte sent to the ULA control ... />
Description
This defines a user-defined function, which can ... -
z88dkHello. I'm an spanish user of spectrum (and naturaly of this page). I have a question. I want to start to program games with z88dk, but I need a goo…
... be more general in the byte ordering. I'd also like ... $ to my code file using a byte ordering that captured attr only ... quickly as looking for a special transparent colour byte during draw. Another ... an option to allow a single constant mask byte to preceed the ... -
Getting attribute location from a screen coordinates (x,y)I am having trouble figuring out how to convert an x,y coordinate pair (pointing to a specific pixel) to the location of the attribute for the block …
... the vertical pixel row within a character
LLL = ... character line (0-7) within a block
CCCCC = horizontal ... indicates the pixel position within a byte. 0=leftmost pixel position ... the attribute address corresponding to a screen
; address ... -
United 93, Even Rumsfield Said they Shot it Down :-[url]http://www.youtube.com/watch?v=x6Xoxaf1Al0&feature=Views&page=5&t=t&f=b[/url]
How about we just flip a coin
or better still I'll write a program in Basic to do it then submit it to this year's crap games compo. -
Self Relocating CodeOn page 47 of [url]http://www.tim-mann.org/trs80/doc/ldosq1-3.txt[/url] is an article about relocating code. The documented routine that performs the…
... br /> ADD A,(HL)
LD (HL),A ;reloc low byte
... br /> ADC A,(HL)
LD (HL),A ;reloc high byte
... INC DE
LD A,(DE)
DEC A ... of first address to relocation, a byte. It is followed by ... -
In Machine Code, what is the quickest way to sort bytes?I am playing around with some ordering of sprites, where I want to order them by vertical position. I used some Rodnay Zaks code to order some bytes…
... reserve one N-byte long, 256-byte aligned "page", ... br /> ld l,a ; A = byte
ld (hl),a
The second pass would just scan the N-byte ... to test via INC A). This implies that ... 't be used as a "normal" value though. ... -
Sprite adviceHello. So, I'm slowly getting to grips with Z80 assembly - currently equal parts frustration and enjoyment. Now looking for some advice to help shift…
I realise that this is pedantry of the highest order, but would it not be better to switch the sign of the accumulator with NEG rather than CPL:INC A ?
It should save you a byte the next time you enter the minigame competition.
:) -
Sprite adviceHello. So, I'm slowly getting to grips with Z80 assembly - currently equal parts frustration and enjoyment. Now looking for some advice to help shift…
... NEG rather than CPL:INC A ?[/QUOTE]
i think CPL ... ]
It should save you a byte the next time you enter ... dissertation i have to program a rather huge piece of software ... -
Pimp my code...Erm, this is just the result of a mental exercise - I wanted to repeatedly display a UDG but decided against using a ROM routine and UDGs! Any sugges…
... necessarily writing the same byte to a block of memory. ... cycles. LDI does supply a byte counter function that if ... lessen the impact of the byte counter:
... 13.8 cycles per byte written. An LDIR takes ... 7 cycles per byte. A hell of a lot faster but ... -
The Only Reason Sinclair Succeeded (Provoking Controversy)Although I love my Sinclairs dearly, I think that the only reason they succeeded was because at the time most people did not know any better (factori…
... hw support) is a fast byte copy (for copying a back buffer to ... possible to do the byte copy at a speed of 13-15 ... 5-6 cycles per byte. Given that a byte load and store on ... a 6502 is already 5 or ... -
Pixel Explosion CodeJust a little snippet to cause explosive effects. It uses table lookups for the screen address, and can handle up to 32 pixel particles. A particle…
... "cp 0". As there is a flag-bit which can be ... effect. So...
ld a,(activeparticles)
cp 0
ld a,(activeparticles)
or a
jr nz,lp1 ... will save 3tstates, and also a byte of memory. -
Programs detecting Spectrum modelsHi. I'm curious about knowing how some speccy games detect if they are runnning in a 128k or 48k model. What tricks can be used to make this in a Spe…
... , you map in a 128k page and write a byte somewhere into paged ... (second) value because the original byte gets simply overwritten. In assembly ... (c),a
ld (hl),a
dec a
out (c),a
ld (hl),a
inc a ... -
Scrolling Loader CounterPlease can someone help me with writing a scrolling counter for a loading system. I like the Hewson counter so i`ve taken the font from zynaps loade…
... repeat:
ld a, (de) ;take a byte of gfx
... "(gfx_of_number)" pointing to second byte (=line) of char
or a ;setting CY=0
... -
The BASIC ISRFirst of all, excuse me if my blatant ignorance about this topic makes me write some nonsense :) The thing is that I'm finishing a game in mixed BAS…
... way) would be to have a MC routine that sets up ... . This routine would check a variable (or a byte of memory you've ... if you're using a RAMDisc then that's a bit iffy :) -
tips on optimizing assemblyI wrote a small routine to rotate right a whole screen character line complete with attributes. This is my third ever assembly routine, so I guess i…
... the first ldir. This saves a byte and 3 t-states. Sounds ... -
tips on optimizing assemblyI wrote a small routine to rotate right a whole screen character line complete with attributes. This is my third ever assembly routine, so I guess i…
... the first ldir. This saves a byte and 3 t-states. Sounds ... -
"chunky" gfxHas anyone some experience with coding "chunky" gfx routines ? (chunky is something like this [url]http://www.pouet.net/prod.php?which=13204[/url])
... allows store 4 pixels in a byte. i did some quick ... ;7
ld (de), a ;7 lower byte
inc e ;4 ... ;7
ld (de), a ;7 lower byte
dec d ;4 ... -
Fuse 0.8.0pre1It's been [i]far[/i] too long since a [url=http://fuse-emulator.sourceforge.net]Fuse[/url] release. The code is finally reaching a state where it is …
[QUOTE=glancaster;168909]I was a bit disappointed to find that ... " patch from Darren Salt, submitted a few days later (but apparently ... opinions I am likely to flip a coin to choose one to ... -
The 150 pound home computerWe missing out on this still ... I think. I know the PC market has wrecked all chance for any alternatives to ever have a hope but ... what if. :lol:…
... the appeal. The Sprinter offered a modern Z80 based hobbyist computer ... realistic graphics. That rules out a lot of non-artists. Whereas ... not expecting everyone to be a great artist the problem comes ... this display would be a byte per pixel. A doubling of data for ... -
Question about digitized sound and videoI searched the forums and couldn't find the answer, so here it goes. Regarding digitized sound: I remember reading an article long ago about a vid…
... Sample Tracker which comes with a large number of sampled instruments ... as LOAD SAMPLE; obviously a bit of a user-interface error there ... memory available from something like a SD or compactflash card attached ... two four-bit samples in a byte, this means all of 5 ... -
Cybernoid editorSo, my long tern goal is to make my own Cybernoid or Rex like game (see an ancient thread about Sprite advice)...but my skills are somewhat lacking..…
... the bytes, and incrementing a subcount for as many times ... ($C700)
dpos is just a byte counter through the uncompressed screen ... br /> ct is the compressed byte total.
sbct is the ... getting closer and closer to a useable editor :-)
... -
Elite / MagratheaI remember one of the magazines (And my memory was convinced it was Your Sinclair) ran an April Fool's tip advising of a hidden galaxy in Elite. Thi…
... high, Zombie Zombie had a maximum height of four blocks ... Each column was held in a byte of data, so what Sandy ... Zombie Zombie, you'd get a very weird thing - either ... />
I might have a crack at replicating that this ... post some screenshots or a snapshot... -
Elite / MagratheaI remember one of the magazines (And my memory was convinced it was Your Sinclair) ran an April Fool's tip advising of a hidden galaxy in Elite. Thi…
... high, Zombie Zombie had a maximum height of four ... Each column was held in a byte of data, so what ... Zombie, you'd get a very weird thing - either ...
I might have a crack at replicating that this ... and post some screenshots or a snapshot...[/quote]
My little first set of routines.Hi all, I just coded a little set of routines just to draw a screen on video mem and a fade out. I could have just copied the screen rendering rout…
... faster than yours and save a byte of code. Couple of little ... .
Just had a quick glance at the fade ... -out code and a couple of little things ... do anything when A = 0. That will save a few bytes ... end of your game every byte you can save will be ..."Lost" 48K expansionToday I dug up my Speccy after more than 10yrs of inactivity. I bought it as a 16K in 1983, than I had expanded to 48K and never had problem. Until t…
... working at all, there was a short assembly language memory tester ... that's as dead as a doornail), a little understanding of how ... at address 32768 (the first byte of upper RAM) which indicates ... simultaneously to read or write a byte.
Therefore, if ...Anybody know what program can:Does anybody know of a PC program (or a "set") that can scan through a BASIC program, and replace "D*, D1 or D2" with two spaces. Then, save that sc…
... The +MGT format is a byte for byte image of the data ... br />
Is there a published spec for the format ... The RealSpectrum site has a fair bit of info on ... .
When a basic prog is saved to ... help speed up testing after a search and replace.
...Anybody know what program can:Does anybody know of a PC program (or a "set") that can scan through a BASIC program, and replace "D*, D1 or D2" with two spaces. Then, save that sc…
... The +MGT format is a byte for byte image of the data on ... remember.[/QUOTE]
MGT is a raw sector dump, but the ...SpeedloadersWhen was the first time they came out and who invented them. What was the general speccy user's and media reaction to them? Would be nice to have a …
A simple kraplock demo with all ... but it uses a few tricks for RLE and byte completion if ... all remaining bits in a byte are 1s or 0s.
