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Another 48k Speccy acting as a 16K model.Hi all, I originally was going to post asking for help to fix the new addition to my family a very nice condition Issue 2 sold on ebay as a 16K model…
... quirk of the 6C001E-5 ULA dunno.
Just wish my ... -
ZX Diagnostics v0.35 ReleasedHi all, I'm pleased to announce the release of zx-diagnostics v0.35, downloadable from [url="https://github.com/brendanalford/zx-diagnostics/relea…
... /Sinclair joystick to select testcard / ULA / soak testing
- Add countdown ... with Timex port conflicts during ULA test
- Handle rollover of ... -
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…
... 16K. Also that when the ULA is drawing the screen it ... it is "contending" with the ULA for access to the data ... and the ULA has priority. With this in ... -
LnxSpectrum - one of the best emulators?Anyone is using the LnxSpectrum? Supports DivIDE (master and slave, up to 1MB of memory), RTC, DMA (!), SAA and 2xAY, ULA+, K-Mouse, CPU up to 20 …
... ), RTC, DMA (!), SAA and 2xAY, ULA+, K-Mouse, CPU up to ... -
ZX Spectrum 48K it only shows colored barsHello, I'm new to the forum and I need help with a ZX Spectrum 48K which I bought recently unfortunately defective. I want to mention that before t…
... RAM issue or (worse ) a ULA one.
I checked voltages ... the RAMs or/and the ULA processor?
Thank you ... -
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…
... .
The problem is ULA snow. Snow appears if the ... -
Need help from people with a +2A/+3Started a topic [url="https://www.worldofspectrum.org/forums/discussion/55141/need-help-from-people-with-a-2a-3"]here[/url] to get a broader reach, b…
... do this anyway), and skip ULA/bus polling on a +2A ... -
Some questions about the Timex TC2048/TC2068I have been doing some research about the specs of these 2 machines but I suppose it would be better to ask for advice in the forum since I have neve…
... /> They both use the same "ULA" (SCLD) but only the TC2068 ... -
Memory Contention: A Hypothetical Fix?I have just had this crazy thought: If one were to wire an additional memory chip, say a 6264 8Kx8 SRAM, in parallel with the main memory so that it …
... sets of RAM, while the ULA/ASIC is wired to read ... the same address, that the ULA is reading from, would halt ... -
ZX Spectrum +3 repairI have my first +3 here, and it needs repairs. Hoping someone here can help me out. When I power it on I get this screen with black and white line…
... to test would be the ULA, but since this a part ... -
Third-party ZX81 RAM packsOne of the things that's previously held me back from fishing for a ZX81 on eBay - other than "will the ULA on this machine sold as 'untested' be com…
... eBay - other than "will the ULA on this machine sold as ... -
Help with transistor replacement in audio ampHi folks, I'd like to replace two of the transistors in my audio amplifier which I suspect are causing crackling noise in one of the channels. Ori…
... in the original 1980s Toshiba datasheet ([url="http://data.datasheetlib.com ... and 700 as per this datasheet:
[url="https://www ... -
48k packed up after cap changeHi all, I'm relatively new to the Sinclair world, my 8-bit repairs in past was lurking in the dark sides of Acorn, Amstrad and Commodore! I've got…
... the ROM and/or ULA. Swapping the ULA from a known good ... -
ZX Spectrum Issue 2 - 12V badHey there, I'm currently attempting to fix a ZX Spectrum issue 2 that I recieved. Overall the machine was generally working when I recieved it, bu…
... s-video modded by me. ULA & LM1889 are confirmed working ... -
Got Myself a 128K “Toast Rack”! (Plus a simple audio fix guide.)I got myself a 128K Spectrum off of eBay the other day. It’s in pretty good nick, but the membrane went the way of the dodo sometime during shipping …
... two resistors that mix the ULA and AY audio to make ... -
Timex Sinclair palette in FUSE?Does FUSE support the Timex Sinclair colour palette? I've tried running appropriate software and rom but the palette stays the same as the Ferranti U…
Does FUSE support the Timex Sinclair colour palette? I've tried running appropriate software and rom but the palette stays the same as the Ferranti ULA. -
Nasty vertical pattern on a 128K Toast Rack via RGBI managed to fix the busted membrane on my [url="https://www.worldofspectrum.org/forums/discussion/55755/got-myself-a-128k-toast-rack-plus-a-simple-a…
... . Playing sounds, both via the ULA and the AY, also affects ... suspect a fault with the ULA (or some sort of capacitive ... same RGB signals as the ULA outputs to the 8-pin ... inputs that leaks into the ULA’s signals and into the ... -
Finally got myself a 128k toastrack too ! :)Hi all, I recently bought a vintage computers lot on eBay, just because there was a toastrack inside (and a better looking CPC 6128 with edge conne…
... issue 6U with an Amstrad ULA.
[img]http://bugpat ... -
New colour palette for Spectrum emulators, 16K/48K/+ machinesI’ve made a colour palette for 16K/48K/+ machines, based on the YUV voltage tables in Chris Smith’s book The ZX Spectrum ULA. This colour palette …
... ’s book The ZX Spectrum ULA.
This colour palette ... use the original Sinclair Ferranti ULA, 5C102E, 5C112E or 6C001E. It ... -
Broken Issue 2 - likely culpritsI've just got hold of an issue 2 spectrum with an interesting layout (heatsink is vertical and goes down to the speaker, some variable resistors and …
... . I'm assuming z80 and ULA are working for it to ... -
Whats the name of the chip that replaces the ULA?I can't find it through searching using the above title. I distinctly remember reading about a new type of programmable chip that can be set to behav…
I can't find it through searching using the above title. I distinctly remember reading about a new type of programmable chip that can be set to behave like different processors. Anyone? -
+2 crashes upon pressing some keysYears ago I purchased off ebay a mint condition, Dixons special offer boxed UK-made issue 1 +2. I did not use it so much until recently however, focu…
... of test programs for the ULA and RAM, first [url="http ... -
Fixing a poorly Issue 3 - Odd faults.Here's one for you Spectrum fixers, I warn you it's a long one. I've spent a couple hours this evening doing several repairs on a rubber keyed Speccy…
... missing on the emitter. The ULA was also getting hotter than ... resort I tried swapping the ULA with a known working one ... -
Testing an Interface 1As title, is there an easy way on how can I test to see if its functional or not please ? :) Please bear in mind I do not have *any* microdrives n…
... recall a faulty Z80 or ULA can make it appear broken ... -
SLAM48 ula will have a PAL/NTSC selector?So I read that elsewhere, however is it a rumor or is it confirmed? But is that even possible?
So I read that elsewhere, however is it a rumor or is it confirmed?
But is that even possible? -
ZX81 composite modHi guys. I have picked up a ZX81 untested for a few quids. I do have a problem tuning it correctly on a Crt TV. I cannot get better than a wavy black…
... press keys). I assume the ULA may be ok but ram ... is an issue 1 with Ula marked 2C184E.
thanks -
How are LAST-K and FLAGS set on a Real Spectrum?Hi, I'm writing a Spectrum emulator and I've got Horace and the Spiders working (with the wrong colours and no sound) but when I boot into ROM non…
... a real Spectrum by the ULA but I couldn't find ...

