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Spectrum 128K +2 problemhello, i am try to repair my spectrum 128k +2 grey, i remove all ram chips and i have some new ones spares, now i have remove all ram chips, i want …
... bit computers are due to faulty RAM chips.
[URL="http://hardware ... -
Spectrum 128K +2 problemhello, i am try to repair my spectrum 128k +2 grey, i remove all ram chips and i have some new ones spares, now i have remove all ram chips, i want …
... bit computers are due to faulty RAM chips.
[URL="http:// ... your question you mean all ram chips on? and which of ... /> i have only 8 ram chip bases, can i do ... dont want to solid the ram chips on and then remove ... dint test it with all ram chips on the working ... -
Spectrum 128K +2 problemhello, i am try to repair my spectrum 128k +2 grey, i remove all ram chips and i have some new ones spares, now i have remove all ram chips, i want …
... bit computers are due to faulty RAM chips.
[URL="http://hardware ... -
Spectrum 128K +2 problemhello, i am try to repair my spectrum 128k +2 grey, i remove all ram chips and i have some new ones spares, now i have remove all ram chips, i want …
... unfamiliar, contended or not ram, pages, data line and ... data adrress,ram banks...
... -ic24? that is conteded ram? wich means that is ... ?
test ram rom file was 8k,edited ... any way to identify that faulty ram ic?
... -
Flashing coloured blocks - diagnosisHiya, hope this is the right place for this... Was given an Issue 2 48K by a someone yesterday that hasn't been powered on in 20 years, which works …
... contacts.[/QUOTE]
The upper RAM is soldered to the board ... it successfully checks the lower RAM?
Will definitely be ... comes to swapping out the faulty RAM. -
Flashing coloured blocks - diagnosisHiya, hope this is the right place for this... Was given an Issue 2 48K by a someone yesterday that hasn't been powered on in 20 years, which works …
... circuitry in the RAM chips? If replacing the RAM doesn't do ... />
I think replacing the faulty RAM will solve the problem.
The RAM chips are responsible for dealing ... control signals for the upper RAM.
Also, once ... -
another faulty zx spectrum +2 to fix!!!Hello to all, I'm new here... I have got a faulty +2 (gray) and start to try fix it... I have read the treads of xaris_sm and Pluto63 as background…
... bases with the remain old ram...[/QUOTE]
While I ... removed all ram chips instead of the only obviously faulty ones, as ... now have a working contended RAM bank (which explains why you ... test means you have a faulty RAM chip. Any negative test means ... -
Repairing a torn trace on an Issue 2 PCBI've found what I think could be the reason for my Issue 2 board not working properly... There is a torn PCB trace beneath one end of where a new ULA…
... on TR4 ZTX650.
Faulty RAM chips rarely get hot - they ... -
Corrupt paper on zx spectrum 48kHi. When I power up my spectrum (issue 3) I get the light grey border, but the paper is black and it switches between thin red vertical lines and thi…
... way to detect a bad RAM chip without using the ... to the top of possible RAM and then fills it ... beyond working out how much RAM you *probably* have!
< ... ve never actually had a faulty RAM or ULA issue with a ... a Dragon 32 with bad RAM.
If you ... -
harvard architecture spectrum clone.I got my first +2 before christmas. I'd never given the 128k spectrums much thought, always been a 48k rubber key tradionalist. :smile: I've been me…
... banks of 8k from 128k
0xA000 RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM RAM
to ... banks of 8k from 128k
0xC000 RAM RAM RAM RAMFixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... to work out where physical RAM finishes. It is not ... full 48k of RAM even with a faulty RAM chip (or less ... needs an area in RAM to store return addresses ... to use the "upper" RAM. So sometimes the ROM program ... display before the "upper" RAM fault causes the CPU to ...Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... to work out where physical RAM finishes. It is not ... full 48k of RAM even with a faulty RAM chip (or less ... needs an area in RAM to store return addresses ... to use the "upper" RAM. So sometimes the ROM program ... display before the "upper" RAM fault causes the CPU to ...Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... bus, or there is a faulty RAM. Any of these will cause ...Fixing my old ZX Spectrum 48K issue 4AHi Guys, I trying to fix my old Spectrum 48K. Looks like my dad used a wrong power supply as the ULA had a bit missing and so did the 7805. So I rep…
... bus, or there is a faulty RAM. Any of these will cause ...128K shadow screen?Hi How does the shadow screen feature work , and how can it be used?
... , 'annoyingly'.
The 128K of RAM is divided up into 16K ... the top third of the RAM address space. You'd wish ... to the bottom third of RAM, but you can't. If ... 7 into the top of RAM, and write to it there ... in the bottom third of RAM and Bank 7 in the ...Seriously weird Issue 2 issue... (RAM-related)Hi guys; I have been trying to fix up my Issue 2 and have run across a bizarre issue that I haven't seen elsewhere in the forums. Hopefully one of …
It sounds like a faulty 4532-20NL3 DRAM chip ... for a 48k RAM machine. But the faulty RAM chip is corrupting ... could also disable the upper RAM (see [URL="http://www ... re-enable the upper RAM (switch in the off ... find out what the upper RAM is actually doing.
...Faulty 48+ Help NeededHi, This is what I get when I plug in the spectrum, this is tuned in. Vid shows a reset. Any ideas, or pointers on the first thing to check. Keyboa…
... ) you need to isolate the faulty RAM chip.. usually by taking them ...Faulty 48+ Help NeededHi, This is what I get when I plug in the spectrum, this is tuned in. Vid shows a reset. Any ideas, or pointers on the first thing to check. Keyboa…
... ) you need to isolate the faulty RAM chip.. usually by taking them ...Issue 4s - Not 'Jailbars' but lines alloverIt's not another 'Jailbars' question!, but I've got this Issue 4S that aside from the 'Jailbars' on the Paper area of the screen which I can live wit…
... as is, nothing apart from faulty RAM IC's replaced - nice clear ...What did the QL come with ?Just wondering this. :) What was actually 'in the box' so to speak for a QL ? Obviously the machine itself and power / tv lead. Blank carts ? Demo…
... or it may have had faulty RAM, unfortunately I lost the machine ...+2 DIAGNOSTICSIs there a diagnostics test available for the spectrum 128 (+2) in tzx format? I've just obtained a spectrum +2 Grey and all looks fine with it on f…
... :
; ---------------
; Fatal RAM Error
; ---------------
; Set the ... which RAM bank was found faulty:
; RAM bank 7 - Black.
; RAM bank ... 6 - White.
; RAM ...Features that are still wanted in Spectrum emulation.Features that are still wanted in Spectrum emulation. 4 USB joystick/gamepad input for real multiplayer games - Yes, Bomb Munchies.... - Sinclair 12…
... Kempston and a single-joystick Ram Electronics interface, and I suspect ... four separate one meg external RAM packs to it, but you ... halves of a load of faulty RAM chips is another matter entirely ...64k speccydoes anyone have instructions on how to use the extra 16k found in some spectrums?
... the multiface map their own RAM chip over this address space ... some higher capacity RAM chips that were half faulty so bought cheap ... you'd want to use faulty RAM is beyond me!64k speccydoes anyone have instructions on how to use the extra 16k found in some spectrums?
... the multiface map their own RAM chip over this address space ... some higher capacity RAM chips that were half faulty so bought cheap ... you'd want to use faulty RAM is beyond me![/quote]
Spectrum +3 blinking yellow/blueI received a +3, which only gives a yellow/blue blinking border during initialization. Pressing BREAK when powering on does not work, neither does a …
I was afraid it´s faulty RAM - thanks Amstrad for removing the RAM sockets on a +3...
Yes Brendan, I do have ZXC3 (and ZXC4) cartridges. Would love to try your test program. My address is shown on my web page.Spectrum +3 blinking yellow/blueI received a +3, which only gives a yellow/blue blinking border during initialization. Pressing BREAK when powering on does not work, neither does a …
[quote="schombi;835388"]I was afraid it´s faulty RAM - thanks Amstrad for removing the RAM sockets on a +3...[/quote]
Look on the bright side... You only have to desolder two chips instead of eight :DHow did bank switching work on the 128K Spectrums?I'm new to Z80 and ZX Spectrum. So I was wondering how the 128+ models managed to work with more than 64K of memory? I'm somewhat familiar with h…
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On the Spectrum 128K, it can swap different ROMs ... of address space (the 128K ROM or the original 48K ... is the middle 16K of RAM. Then, any of ... Those eight blocks total 128K of RAM. You swap in the ... setups that have 64K RAM available, though not in ...Memory testersHi, Just wondering which software people are using to test the memory in their spectrum. I have been using Zorn's memory tester as described here:…
... TC2068, so will have identified faulty RAM IC's based on the ... faulty, and I can cross reference the bits to the actual RAM ...Vertical Lines Spectrum +3Hi, My Spectrum +3 boots up and shows the following: Grey border with vertical black lines: http://www.sinclairzxworld.com/viewtopic.php?f=22&p=19…
Quite likely to be faulty RAM, they don't need to ... get hot to be faulty - just means they've not ... too much current. I say faulty RAM, as it's the first ...+2 Gray ProblemI'm trying to repair a +2 gray that behaves differently at every boot up. Some rare times I can get the selection window but pretty soon the characte…
I'm not overly familiar with Paul's RAM tester, but I have a fully socketed grey +2 that I can swap some faulty RAM into, and see if I can reproduce your error. It'll be later this evening though :)
B
