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Double Buffering Artefacts on Real HardwareI have a project that I've played around with for a while and always tested using emulators, either ZX Spin or Spectaculator. It is a 128k game th…
... causes screen corruption if the I register contains a value between 40h ... problem and, as far as I'm aware, no emulator attempts ... -
128K memory bank selection to avoid contention issuesI'm currently developing a game and I'm trying to get my head around the memory contention issues of the various 128K/+2/+2A/+3 spectrum models in or…
... of processing logic that I'm implementing for various ... stuff.
I hadn't considered the uncontended ... with this in mind I see I can safely move the ... again.
I read somewhere though that if ... shouldn't set the I register to a value in ... -
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…
If you point the I register to 37, you can use ... but this is the one I use on pretty much all ... all models, as far as I can tell, using emulation. Even ... -
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…
Is using the I register cheating a bit? I'm now at 774 bytes!
I'm doing my best to comment on the source and try and make it understandable. I will post it soon, when I've saved some more bytes! -
Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... hardware bugs. If the "I" register points into contended memory, snow ... the display. If the "I" register points into contended memory and ... :)
[quote]
I think you should work on ... my contributions are overstated :) I just helped a bit with ... -
Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... of hardware bugs. If the "I" register points into contended memory, snow ... on the display. If the "I" register points into contended memory and ... -
Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... of hardware bugs. If the "I" register points into contended memory, snow ... on the display. If the "I" register points into contended memory and ... /> [/quote]
Actually, I haven’t been able to ... machine crash when I set I to $40–$7f. I get the snow ... -
Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... of hardware bugs. If the "I" register points into contended memory, snow ... on the display. If the "I" register points into contended memory and ... /> [/quote]
Actually, I haven’t been able to ... machine crash when I set I to $40–$7f. I get the snow ... -
Gandalf [z88dk][Nirvana Plus][128Kb]Gandalf 1.00 [url="https://drive.google.com/open?id=1T9HK0_isoMrfogSIJVhPGehjVIdFus4c"]Download Ver 1.00[/url] Long after the destruction of t…
... of hardware bugs. If the "I" register points into contended memory, snow ... on the display. If the "I" register points into contended memory and ... /> [/quote]
Actually, I haven’t been able to ... machine crash when I set I to $40–$7f. I get the snow ... -
The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... actual ULA [i]snow[/i] effect, rather than a crash (i.e. ... effect kicks in if the I register is in the $40–7f ... snow effect will appear [i]as long as bit 6 ... the snow effect, even though I is set to $f7, ... the point.)
I’m only saying this, because ... -
The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... , setting bit 6 of the I register when a contended RAM bank ... date)[/quote]
Ideally, yes. I think they ran out of ... $5B5C var elsewhere).
I’ve seen a few games ... -
The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... b] immediately.”[/quote]
I'm pretty sure he meant ... /> ld a,$c0
ld i,a
ld a,%01010000 ... up a special version of [i]Yankee[/i], which pages in Bank ... a snippet that changes the I register within my ISR (with the ... -
The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
[b][u]The I register pointing to $40–$7f causes ... ?[/u][/b]
I think the cause of the ... The contents of the refresh register (R) are placed on ... the contents of the interrupt register (I) is put on address ... [/url]
[b][i]Mark[/i][/b] -
The I register pointing to $40–$7f causes ULA snow and a crash. Or does it?I have heard it from numerous sources, including a few members of this forum, that 128K/+2 machines crash if the I register points to a range of $40–…
... simply reads the R register, places its value into ... mucks about with the I register but restores it prior ... from various memory locations, i.e. contended/non-contended ... 1. No matter what I tried, I could not cause a ... by setting the interrupt register to $40–7f but ... -
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, …
... to 666 bytes, but thankfully I saved elsewhere and its 665 ... are achieved by manipulating the I register to point to different pages ... the 81 to handle, though I've seen impressive isometric stuff ... -
Grey +2 with lines on some games on RGB connectionHi Everyone, Is it OK if I ask a question? I dug my +2 out of the loft after far too many years about a month ago, and I have finally got it ba…
More info on the ULA rain/snow effect: https://www.worldofspectrum.org/forums/discussion/55839/the-i-register-pointing-to-40-7f-causes-ula-snow-and-a-crash-or-does-it/p1 -
Grey +2 with lines on some games on RGB connectionHi Everyone, Is it OK if I ask a question? I dug my +2 out of the loft after far too many years about a month ago, and I have finally got it ba…
... .org/forums/discussion/55839/the-i-register-pointing-to-40-7f-causes ... /> Thanks also for your assistance, I really appreciate it :) -
MB03 UltimateDear ZX friends, you may have heard of MB-02+, probably the best disk interface for ZX Spectrum, originated back in the 90's. Although not much sp…
I have an MB02 :) How do I register an interest? :) -
MB03 UltimateDear ZX friends, you may have heard of MB-02+, probably the best disk interface for ZX Spectrum, originated back in the 90's. Although not much sp…
[quote="vanpeebles;953876"]I have an MB02 :) How do I register an interest? :)[/quote ... -
I love WoS.There ... I said it. What do you mean, you're hard of hearing? I said I LOVE WoS! I mean, that's it, that's all. Like I said the othe…
... was five years ago. [i]Five[/i] bloody years. Has time ... didn’t I register sooner? Who knows . . . I guess I felt I couldn’t ... a treat.
I remember downloading the TZX files ... priorities.
[img]https://i.postimg.cc/sxvv8SV6/GoD.jpg ... -
Multi-tasking OS on the Spectrum?Do you think it is possible to build a multi-tasking operating system on the Spectrum? That is, most important the ability to have several task run…
... at runtime... in fact, I wouldn't be surprised if ... into Turing-machine-violating territory. I haven't thought it through ... change addresses on the fly i.e. dynamically relocate)
... with in similar matter (hooking I register instructions, EI/DI, and IM ... -
I am completely new to this (about the FTP)Please forgive me if this is forbidden. See for logging into the FTP site? (I understand there's mirrors or something) do you need to register a user…
Please forgive me if this is forbidden. See for logging into the FTP site? (I understand there's mirrors or something) do you need to register a username/password? as I now can'c connect to the FTP. :( -
Is the IY register used by the spectrum rom?Hi I've been writing a sprite routine and have noticed that the sprite data gets corrupted at some points. I have no idea why and can only guess tha…
Hi
I've been writing a sprite ... gets corrupted at some points. I have no idea why and ... the problem. Does the IY register need to hold a certain ... -
R Register, Contended RAM and ClonesHi. I've had a quick look at the CSS FAQ but didn't spot quite what I'm looking for (also the CSS FAQ doesn't have much detail of the clones - there …
... progress of the R register. At one point I reset it, and ... contended RAM on the R-register? I do not run any code ... the R-register is internal to the Z80, but thought I'd ... , Scorpion, ...) affect the R-register differently? Again I would guess not as ... -
which domain to register?I'm about to register a domain under my country's top domain. almost all of the keywords are available to buy and I'm a bit indecisive person. which…
I'm about to register a domain under my country' ... are available to buy and I'm a bit indecisive person ... -
Well I'm excited, but I guess you might not beHehe this is as far as I got today, a silly little border program: [PHP] ORG 32768 PROGGY: LD C,255 ; We loo…
...
INC A ; Increment register A
CP 16 ; ...
[/PHP]
I know you'll all think ... is utterly rubbish, but I'm still learning. Quite ... )
( edited as I missed a few lines out ...
