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The new GP2Xpectrum releases threadYeah, I know the thread title isn't exactly too original, but I've decided that just one post to hold all updates makes more sense than a lot of smal…
... )
- I was still applying contention emulation in a place where ... timing, it was taking 8 states instead of 4.
- Improved floating bus ... emulation, now passes floatspy test and other similar ones ... -
Pentagon floating bus timingI wanted to take a little break from working on the ZXDS UI yesterday, so I added support for Pentagon timing instead, so I can finally enjoy the lik…
... added support for Pentagon timing instead, so I can ... has reliable and exact info about the floating bus behavior and timing. An explanation ... the bytes without any memory contention would be nice, too ... the floating bus behaviour that you find on the 48K and 128K ... -
Fast screen writesI wondered what the faster than LDIR methods of writing to the screen were.
... For a full description of contention, I'd recommend that people ... of my sprite rendering and screen drawing immediately after ... you're really careful with timing you could synchronize your ... bottom border by reading the floating bus and looking for a particular ... -
Incorrect Spectrum +3 emulation: different results on Fuse and SpecEmuWhen developing and testing [URL="http://www.worldofspectrum.org/infoseekid.cgi?id=0027591"]Rotatrix[/URL], I noticed different results on Fuse and S…
... thank you for your suggestion and (with Einar) for the ... br /> Machine type: +3
Contention offset: 0x08
... /> Floating bus... skipped (B=0x01)
Contended memory... passed
High port contention ... my +3 a "late timing" exemplar then? -
Spectrum 128 toaster and divide incompatibility problems with some demos and games.Okay so I got this thing now. It?s my first Spectrum ever. [img]http://img836.imageshack.us/img836/2016/speccyl.jpg[/img] [url]http://img824.image…
... require the broken contention of the 128 and the MkI grey ... a resistor to simulate the floating bus (then Arkanoid etc. wiil ... /ZX_Spectrum_128Ke[/url]
And as an added bonus the ... are contended and you will get timing errors on timing critical code ... -
Correction of +2 hardware errorsThis is a collection of various pieces of information picked up from various places, including a lot from this forum. I have edited it and reworded i…
... PAL10H8 ). This is port decoder and memory controller.
... read of port 7FFD (write floating bus data)
- access to ... small incompatibility with original timing in some ZX demos...< ... with original I/O space contention:
[url]http://velesoft ... -
TKMEM - the 128K interface for 16K SpectrumsHello all! Here in Brazil, we have made a small production of an interface, totally based on Velesoft?s memory expansion ([url]http://velesoft.speccy…
... 262 scanlines including retrace and border lines. It'd ... ]
[*] The contention pattern.
[*] Whether spurious contention is applied as ... ones.
[*] The timing of the first pixel read ... IN from an unattached port ('floating bus').
[*] Details on ... -
WIP: ULAPlus hardware implementationThis aims to be an "almost" plug-in replacement for the Sinclair ULA chip fitted in Spectrum 16K/48K/Plus machines. It comes in a form of a small PC…
... portion of the address bus (A0-A6) and keep[B]s[/B ... the contention handler if needed. In other words, [B]the address bus ... B]sive number of floating wires crossing here and there, right?[/QUOTE ... byte as if no contention occured, although the timing would not be ... -
Timing_Tests-48k_v1.0 results...Hello All, I ran these [URL="http://www.zxspectrum4.net/op_timing.php"]tests[/URL] on my emulator and some of the tests failed.. so I tried it on a …
... + is disabled, and it passes tests 36 and 37 as long ... spent on figuring out the contention details [URL="http://www. ... test the contention timing, not the emulation of peripherals (or floating bus, for ... affect the subsequent INs and thus the timing at all. I ... -
Timing_Tests-48k_v1.0 results...Hello All, I ran these [URL="http://www.zxspectrum4.net/op_timing.php"]tests[/URL] on my emulator and some of the tests failed.. so I tried it on a …
... as ULA+ is disabled, and it passes tests 35-37 ... spent on figuring out the contention details [URL="http://www. ... test the contention timing, not the emulation of peripherals (or floating bus, for that ... affect the subsequent INs and thus the timing at all. I ... -
Correction of +2 hardware errorsThis is a collection of various pieces of information picked up from various places, including a lot from this forum. I have edited it and reworded i…
... PAL10H8 ). This is port decoder and memory controller.
floating bus data)
- access to ... small incompatibility with original timing in some ZX demos...< ... with original I/O space contention:
[url]http://velesoft ... -
Interrupts, 16k Spectrums and snowI'm writing something for the 16k Spectrum and I want to use interrupts. The avilable documentation doesn't seem clear enough for me to figure out ho…
... bottom and top of the screen (and the sides too) where contention isn ... decided to keep the floating bus sync (and I do it on the ... hit at 50hz
2) Floating bus to sync start of drawing ... , but it would iron out timing fluctuations up to about 12K ... -
Fuse/SPIN vs Spectaculator border timingsHello, I'm trying to figure out at which moments the 48K ULA samples the current border color into its internal latch. To do that I wrote a small …
... and 128k/+2 machines and Chris was able to simplify his Harlequin contention ... we have nailed the sampling timing of +2A/+3 machines. ... was believed there is no floating bus to test it with ( ... discovered the difference between +2A and +3 screen paging pattern, ... -
Emulation accuracy and how it affects softwareHi folks. I was thinking of bodging together a rudimentary Spectrum emulator myself, not as a competitor to the other emulators, but as an integrate…
... , but as an integrated (and necessary) part of a Speccy ... />
As for contended memory and finite-speed screen refresh - I ... to run the code correctly and display a barely intelligible ... /> Hardware quirks such as the 'floating bus' effect will also be absent ... -
ANN: SpecEmu 2.3 - Minor UpdateHere's a minor update to the SpecEmu emulator - the emulator with an incredibly small filesize for a Win32 application, and backed up with an incredi…
... filesize for a Win32 application, and backed up with
an ... to some overlooked opcode contention timings.
- Improved floating bus emulation.
- A ... -
A few questions regarding EmuZwinA few questions regarding EmuzWin 1. I have been trying to write a program to generate multicolour effects on the Spectrum,ie more than 2 attributes…
... lot about how that affects timing.
2. When assembling ... one with the correct addresses and the other with 0000. It ... works ok.
4. Floating Bus implementation. I use this to ... I find the Emulator excellent, and it is my preferred choice ... -
A few questions regarding EmuZwinI had posted this in the development forum and then remembered there was an emulators forum, so apologies for the repetition. 1. I have been trying …
... this in the development forum and then remembered there was an ... lot about how that affects timing.
2. When ... works ok.
4. Floating Bus implementation. I use this to ... I find the Emulator excellent, and it is my preferred choice ... -
RUSSIAN SOFTWARE and real ZXRussian ZX games is writed on russian ZX clones and support hardware feature TURBO OFF ( for ZX clone ZS SCORPION ). Russian ZX clone ZS SCORPION use…
... is not supported and CPU read data from floating bus ( value #FF ... ifnored (without effect) and software run always at ... crash (data from floating bus is writed to paging ... paging port data from floating bus (can't be ... paging port data from floating bus (can't be ... -
IN 255 behaviour not emulated in Spectaculator and ZXSpinI'm not speaking about "normal" IN 255 behaviour. All of you know what I'm taking about: IN 255 can be used to "read" screen data as it's retrieved f…
... initiate a bus cycle that might affect contended memory, and the ULA ... the data bus, and the Z80 can only read FFh (floating bus).
and 7Fh.
A real Spectrum only contends the I/O bus ... cycle if A8-A15 falls between the mentioned range, AND ... -
Emulating the 128KeIt occurs to me that I wasn't frequenting WoSf when I created the 128Ke standard, which means some people haven't heard of it. Here it is: [url]http…
... legal Sinclair branded machines (and even some clones) can ... br />
AY sound and all the 128 software.
contention that crashes the original 128 ... plus software that requires the floating bus. 128 software that requires ... -
A new ZX spectrum cloneOver the past 12 months i have been developing a new spectrum clone as a hobby project to waste my spare time on. It is still not fully complete yet …
... with 48K display timings
Floating bus and contention emulation model (not cycle accurate ... the border shows up the contention model inaccuracy.
Things ... :
Improve and expand the BASIC extensions
Improve contention model to ... -
Using even ports for input?I've been looking for unused ports to use with my clashbasher interface. I understand that the spectrum only considers A0 when decoding its input p…
... with resistors. And the high byte of the address bus is used ... spectrum seems uneffected by this and still loads games normally afterwards ... shouldn't be any contention on the bus because that's the ... on a spectrum with a floating bus it should be fine shouldn ... -
Understanding contentionI'm trying to understand contention and its implications when some "weird" bus cycles (such as I/O cycles with I/O addresses in the contended memory …
... to understand contention and its implications when some "weird" bus cycles ... and $7FFF, there is both memory and I/O contention. Memory contention ...
Also: memory contention makes T1 to be enlarged ... instance, to avoid memory contention) that begins at ... -
[NEW] Retro Virtual Machine v1.0.0 for OSX released!!!!Here it is! Retro Virtual Machine v1.0.0 RELEASED!!!! Many thanks first to Patrik Rak for the PZX format and for their Z80 tests without which RVM…
... br /> Emulation of the ‘floating bus’
Emulation of the ... Tape recording for any block timing.
Disk ... volume.
Low pass and high pass filters.
... Hot plug detection of gamepads and joysticks.
Buttons assignment ... -
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…
... /> As well as small integers and floating point decimals, a slightly trickier ... />
Here's the BASIC timing routine which I use. The ... in line 9994. The first timing should be done with 9994 ... get the loop overhead. The timing for that is then deducted ... -
Interrupts, 16k Spectrums and snowI'm writing something for the 16k Spectrum and I want to use interrupts. The avilable documentation doesn't seem clear enough for me to figure out ho…
... something for the 16k Spectrum and I want to use ... 's a good idea, and I don't have hardware ... to somewhere between 16k and 32k, and that's obviously the ... case someone suggests using the floating bus - that's what I ... a single frame to execute and I end up losing ... -
A few questions regarding EmuZwinI had posted this in the development forum and then remembered there was an emulators forum, so apologies for the repetition. 1. I have been trying …
... lot about how that affects timing.
[/quote]
It ... details on memory contention.
[quote]
4. Floating Bus implementation. I ... can test an emulator's floating bus emulation accuracy using Ramsoft's ... -
+2A "Ghost" programHi all - first time posting here, so I'll do a quick background - I was a (far too) dedicated 48k and +2A gamer in my younger days. Thanks to the mi…
... 's copying it wholly, and patching the differences? Were ... tendency to rely on and then bodges the tape ... depend on things like the floating bus effect still won't ... loading routines as the timing will be all screwed ... quite a clever trick and not bad as 8- ... -
Games that won't work with the +2a/bIs there a list of all the games that don't work with the +2a/b? Like Fairlight for example. Ta :)
... also the different timings, non-floating bus etc.? Note: I am talking ... effect that depends massively on timing and interrupt tricks.
If ... contains the original 48K ROM and can be activated by an ... -
Which Emulator do you use the most? and whyI currently use ZX32, it's free, which is great but it's not as fast as I'd like. Please everybody, tell me your fave emulator and why. I'm quite …
... into the realms of demos and multicolour rendering, you'll ... and that's not bad at all for a windows emulator. Contention ... need contention (or at the very least some sort of floating bus ... hack) to get some games and applications working ...
