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The direct bus or indirect one... that is the questionThe Ethernet project continues...and I'm in a quandry. So I've managed to implement enough socket library for the W5100 that socket, bind, listen, a…
... fast, it's just a single instruction for an 8 bit register ... -
Index register subtractionHi, Just wondering if there a way to perform SBC HL,BC on the IX or IY registers. I can't find an op code for it, and my assembler doesn't recognise…
Sadly, it can't be done in a single instruction as SBC HL, BC is an ED prefixed instruction and the IX/IY opcodes don't work with any ED instructions.
You'll need to swap some registers I'm afraid!
Marko -
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…
... you can then use the single instruction djnz to Decrease it and ... -
Help understanding some z80 asmI'm trying to work out how to represent the structure of a "sprite" in the SAM as "Grabbed" by SmallC. I can see the assembler implementation but I …
... linkage for functions with a single parameter. The stack is not ... used at all and the single parameter is passed in the ... the former can involve a single instruction and the latter at least ... -
Features that emulators don't haveI believe most of us use more than one emulator, mainly because there isn't one emulator that has all the features we need or want to use. We also kn…
... paused the emulator runs one single frame at each keypress.[/QUOTE ... pressing Pause advances by a single frame and stays paused. Useful ... debugger, which will be a single instruction when stepping, or could be ... -
Features that emulators don't haveI believe most of us use more than one emulator, mainly because there isn't one emulator that has all the features we need or want to use. We also kn…
... debugger, which will be a single instruction when stepping, or could be ... -
Question For The Emulator AuthorsWhy do $ED $44, $ED $4C, $ED $54, $ED $5C, $ED $64, $ED $6C, $ED $74, $ED $7C all disassemble to opcode NEG and $ED $45, $ED $55, $ED $5D, $ED $65, …
... ). By ignoring 3 bits, a single instruction can be accessed via 2 ... -
8-bit or 16-bit registers?I'm playing around with writing a Speccy emulator for mobile Java at the moment. I did a quick and dirty port of Qaop, which does run but at less tha…
... each of those is a single instruction operation.
You "getfield ... -
Please help an absolute novice with some simple(ish) programming.I'm very, very rusty at BASIC. I'm using BASin, for my GCSE Astronomy coursework [quote] Use a spreadsheet and/or a graphing package, or write a com…
... was said, there is no single instruction to create elipse in Spectrum ... -
Thinking in Assembly (first efforts)The following is one small routine to educate myself on a few concepts (jumps, flow control, routines, CPI): [code]searchmem xor a …
... BC = 0, all in one instruction! For example:
[CODE ... for BC = 0 in a single instruction, rather than the four instructions ... -
More colours II (Was: Most popular new features?)The suggested 4xCLUT multi-colour solution never took off.
... not gonna to write any single instruction for not existing hw. well ... -
Total Eclipse & Castle Master possible alternative versions?In Crash Issue 91, page 63, in the first paragraph of the main review text, Nick Roberts mentions that there are special editions created for The Hom…
... 's the poster, plus a single instruction sheet for both games and ... -
Sinclairean A3[B]Sinclairean[/B], a new ZX Spectrum emulator written in machine code for x86-compatible, OpenGL-capable computers. Features: [LIST] [*]Fast machin…
... be removed until not a single instruction of your code lives in ... -
Games in machine codeHi everyone, How do go about doing multiple shots like a machine gun, do you have to store every x and y position of each bullet? When you kill som…
... 't do them in a single instruction :-) Having to constantly shuffle registers ... sure the right register that instruction "FOO" needs is loaded with ... a really compact instruction set (variable length instructions, single instructions doing lots ... -
Games in machine codeHi everyone, How do go about doing multiple shots like a machine gun, do you have to store every x and y position of each bullet? When you kill som…
... on later CPUS. The complex single instruction indexing modes, count based ... with the 875,000 instruction performance of the 3. ... Spectrum in terms of CPU instruction performance... I still love ... use a lot of single instruction indirect addressing modes such ... -
Games in machine codeHi everyone, How do go about doing multiple shots like a machine gun, do you have to store every x and y position of each bullet? When you kill som…
... also use a lot of single instruction indirect addressing modes such as ... stack if you have an instruction like "LD (r4+4)w ... out how long the next instruction will be is as big ... -
designing a computerHi everyone! I am designing a 4 bit computer and i need some advice, is this a good instruction set? [CODE] BINARY OPCODE DESCRIPTION 00000 nop…
... .
RISC (reduced instruction set computer) and CISC (complex ... CPU instructions. SISD (single instruction single data) and SIMD (single instruction multiple data) are also ... accompany the load accumulator immediate instruction. That allowed for 16 ... -
Games in machine codeHi everyone, How do go about doing multiple shots like a machine gun, do you have to store every x and y position of each bullet? When you kill som…
... also use a lot of single instruction indirect addressing modes such as ... registers and very simple, orthagonal instruction sets lend themselves more to ... -
Why doesn't my loop work?Can anyone help me understand why my loop doesn't work? Is it to do with how DEC HL affects the flags? [code] ; Read 32k bytes from port 191 as fa…
... +B-1) with just one instruction!
The non-repeat ... equivalent instruction 'INI' even sets the Z ... than 256 bytes in a single instruction, so would still need a ... -
yeah - unix for zx spectrumI started a new hobby project. An operating system for ZX Spectrum. A unix clone. Talked to my friend about it and he asked me what if after I'm done…
... function pointers (the "jp (ix)" instruction takes 8 cycles), slow 16 ... can be replaced with a single instruction "rlc b"; the end ... for no keys in a single IN instruction (just clear more than ... access by a single producer and a single consumer. You may ... -
writing an emulator-newbie needs helpHi, this is my first post here. I decided to write a minimalistic emulator of ZX Spectrum-no emulation of advanced peripherals, no emulation of sound…
... how ADC (add with carry) instruction really works.
... : is it treated as a single instruction (A := A + B + CF) or ... 4 alternative interpretations of the instruction and I need you to ... br />
Reasoning 3 (one instruction): A is increased by 255 ... -
Newbie says 'Alreet?'Hiya dudes, Just dropping a line to say hello as i've decided at 33 to try and fulfill a long time ambition to write a speccy game in machine code..…
... screen. It isn't a single instruction like at computers with hardware ... -
The most powerful 8-bit machine, and CPU?Further to the discussion in: [url]http://www.worldofspectrum.org/forums/newreply.php?do=newreply&p=621787[/url] What actually is the best 8-bit ma…
... variables. It has a multiply instruction which can multiply 8-bit ... use them well in the instruction set with a nice set ... the U register) with a single instruction, allowing you to shift memory ... -
GUI/OS for the Spectrum?Hi, Is anybody working on a WIMP/GUI system for the Spec? Is there anything current out there? [url]http://snakeoillabs.com/wordpress/2005/10/30/8…
... ;629760]
one-processor = one instruction; no more discussion needed.
single clock cycle in the right ... time since a single processor only worked on a single instruction at a ... -
In Java for ZXHi All I am glad to notify you that I have opened the sources of my J2Z80 translator (0.1 version) which allows to use Java toolchain to generate Z8…
... (to restore stack) with a single instruction. -
GUI/OS for the Spectrum?Hi, Is anybody working on a WIMP/GUI system for the Spec? Is there anything current out there? [url]http://snakeoillabs.com/wordpress/2005/10/30/8…
... multiple instructions in a single clock cycle in the ... since a single processor only worked on a single instruction at a ... time.[/QUOTE]
a single processor ... can execute a single task at a ... -
Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
... It would give you more instruction codes, but you'd ... by making pretty much every instruction *much* slower [/QUOTE]
single instruction, regardless of operands is ... make the pipeline and instruction decoding much, much simpler ... -
Fantasy Z80 instructions?This follows on from something catmeows said in another thread, and that I've been meaning to ask for a while. This may sound daft to people with mo…
... desperately seeking for "mirror A" instruction :)
I would add ... N bits left/right with single instruction.
And I would ... -
The Disciple clone... doable?Hi. As a spectrum user in the 80's this was the dream interface all-in-one for me. I have a 48k+ and planning on get a 128K toast-rack later. Anyway…
... fetches an
instruction from the following addresses:
instruction from the following addresses:
instruction 'ld hl,(0x5b58[I][/ ... the execution of every single instruction (and allows for a ... -
20-column multicolour: a half-baked ideaI was writing an email reply to one Mr Jowett about multicolour routines, and in that way that explaining something to someone else makes you think "…
... a better way. Executing a single instruction [B]ld hl,($4000)[/B ...
