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repaired a 48K, yay :)I just managed to repair one 48K. After socketing all eight lower RAM chips (hard work!) and replacing few of them, it showed the familiar "Sinclair …
im trying to repair a zx spectrum but there is one thing im confused about..
The 4116 chips have 7 address lines and only 16K memory.....where is the other 32 K memory then? Where are the other 9 available address lines??? -
How the spectrum generates the video from ramHi everyon, I know that most people here allready know this but i think i found out how the spectrum acctually dispalys stuff and why the LD x, (HL)…
... reading or writing to the lower 16k of ram in a real ... is the master of the lower ram and even takes care ... -
Compiling Basic to MCHello, I have a lot of long Basic programs. These are mostly strategy programs, good but slow. I was thinking about how to speed them up without com…
... step. First step is the memory lack. I can?t have ... /C at once in the memory of a Spectrum, even when ... Machines are just bank switching 16k Memory, so it might split the ... PC based program without the memory restrictions.
[QUOTE=na_th_an ... -
Zx Spectrum 48k+ black screenHi A friend of mine gave me his 48k+ and when i tried to turn it on I just get a black screen of the TV. I don't have sound of the console. Where c…
... ]
1. Check and or replace CPU
2. Check and ... or replace ULA
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3. Check and replace lower portion of RAM chips
4. Check and replace ULA
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Using a Z80 CPU in a 48K Spectrum?Will a Z80 CPU (which I have) work well enough in a 48K Spectrum to give me an indication as to whether the Z80A CPU in there is duff? Thanks for re…
... the screen. Two of the memory chips run too hot for ... nothing I plan to replace all the memory chips and it would ...Upgrading the Humble Spectrum 128 +2 (Grey)Hello there my fellow WoS'ers I am at a subtle in-pass in my wants for one of my +2 motherboards. I received this mobo, DOA in a job lot from fleab…
... /> so with say, SEBasic in lower 16K of the Boot ROM I ... put that in the upper 16K?
would there be ...Upgrading the Humble Spectrum 128 +2 (Grey)Hello there my fellow WoS'ers I am at a subtle in-pass in my wants for one of my +2 motherboards. I received this mobo, DOA in a job lot from fleab…
... /> so with say, SEBasic in lower 16K of the Boot ROM I ... put that in the upper 16K?
would there be ...Rom Cartridge - How does it work?So I've got me an IF2 and it has this ROM cartridge slot. How does it work? I read Paul Farrows site but one question remains unanswered. If I have o…
... =fog;546421]it replaces the lower ram, or part of it ... find if you have faulty lower ram 4116(?) chips.. as it ... replace lower RAM, only lower ROM.
Question: What will happen if you replace lower ...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…
... the way real Speccy with lower 16K as ROM and upper 48K ...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…
... the way real Speccy with lower 16K as ROM and upper 48K ...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…
... the way real Speccy with lower 16K as ROM and upper 48K ... as the Multiface (changes the 16k Spectrum ROM by 8k ROM ...Requesting a little help to identify the purpose of this 'add-on' to my Issue 2Hi everyone First of all it's my first post here so please go easy on me! I'm grateful to be accepted into your fine little club :smile: I probabl…
... 're lucky its not the lower 16k with the 4116 IC's ...Repairing a faulty 48K issue 2.I am investigating one of a pair of non-working issue 2 48K Spectrums that have been sitting in a cupboard untouched for quite a few years. I haven…
... ULA was not accessing the lower 16K. The resistor decoupled the z80 ...Would anyone be interested in......Hi, I'm wondering if there would be much interest in an expansion card for the speccy that gives a VGA output with enhanced gfx & sound capabilities…
... another 6K of the contended lower RAM for a choice between ... fit two screens in the lower 16K for buffering.
But ... storage, ROM cartridges, maybe the 16K shadow RAM of the [I ...Three faulty machines - help!I have three Spectrums and all of them have suddenly collapsed and I can?t figure out what?s wrong. New here.... I own three Speccies but all of a …
... is a fault in the lower RAM. The two where the ... known good RAM for the lower 16K before investigating further.ROM switch on NMIHello! Please, help me or point in the right direction. I am building a project for 48k spectrum which must activate its rom (actually static ram) …
... sample it with a valid lower 16K address, in other words before ...Would things of been better if the NMI was fixed ?I was just wondering, if the NMI bug was fixed say early on in production, so for instance all issue twos (and late issue ones) and beyond had the "f…
... to page RAM into the lower 16K. As it is, the programmer ...Getting an 14Mhz crystal to oscillate?I am building a circuit with an 74LS32 and a 74LS193 to work as frequency divider. Though I have hit a snag, how to I wire up a crystal to make it os…
... 4164s I have used to replace lower and higher ram. Also I ...Diagnosing a strange software fault in a 48kHi, A friend gave me a 48k, which I am very keen to restore. The spectrum 48k was my first computer over 20 years ago and I owe my ability to code t…
... a Spectrum start as a 16K model.
Use a ... Spectrum to use only the lower 16K of RAM. The output of ...Diagnosing a strange software fault in a 48kHi, A friend gave me a 48k, which I am very keen to restore. The spectrum 48k was my first computer over 20 years ago and I owe my ability to code t…
... a Spectrum start as a 16K model.
Use a ... Spectrum to use only the lower 16K of RAM. The output of ...Migration to NemoBus ideology[B][U]Migration to NemoBus ideology.[/U][/B] Unfortunately all modern western hardware design is based on an outdated ideology bus, which was establ…
... that gets paged into the lower 16K of address space. This is ...Migration to NemoBus ideology[B][U]Migration to NemoBus ideology.[/U][/B] Unfortunately all modern western hardware design is based on an outdated ideology bus, which was establ…
... that gets paged into the lower 16K of address space. This is ...My 48K Speccy has died.Hi fellow WoSer's! Wondering if you could help me with my rubber key 48k Spectrum, which died on me this afternoon. It is one I prevoiusly fixed up j…
It is most likely the lower 16K of RAM that has failed. ... the supply voltage to the lower RAM, make sure all voltages ...Issue 2 problemHeres a video of what happens when I fire up an Issue 2 board ive had hanging around for ages, this is with Paul Farrows RAM test cart in btw If this…
The border turns 'white' (which I've read is done by the Z80), and it looks like a RAM test is being done. So if it's one of the causes you mention, I'm betting lower 16K RAM.
Btw. did you check supply voltages?Red DwarfA Red Dwarf video game - good or bad idea? (given its recent resurgence in popularity in the UK) My ideas: [b]Plots[/b] - An interquel which bridg…
... can all go in one 16K memory bank, then the levels in ... tiles in a level, a 16K bank could still hold hundreds ...Jim Bagley's ZX81 Racing game released.[url=http://tinyurl.com/JimBagleySpeccy]This guy[/url] has just released a 16K ZX81 game which uses the WRX high resolution schema :-) Download it n…
... since it requires a special memory expansion pack. The problem is ... (static RAM), but the original 16K memory expansion pack that Sinclair sold ... ZX81, since the internal 1K memory was SRAM. However Dr BEEP ... real hardware without a special memory pack. I don't ...Jim Bagley's ZX81 Racing game released.[url=http://tinyurl.com/JimBagleySpeccy]This guy[/url] has just released a 16K ZX81 game which uses the WRX high resolution schema :-) Download it n…
... since it requires a special memory expansion pack. The problem is ... (static RAM), but the original 16K memory expansion pack that Sinclair sold ... ZX81, since the internal 1K memory was SRAM. However Dr BEEP ... real hardware without a special memory pack. I don't ...Issue 6A trouble[url=http://postimage.org/image/xp4rtmfp1/][img]http://s18.postimage.org/xp4rtmfp1/P040213_13_34_01.jpg[/img][/url] Only socketed chip is ULA which …
Lower 16k? I usually get something with the tester if thats the case, not the same result, unless you meant elsewhere?Issue 6A trouble[url=http://postimage.org/image/xp4rtmfp1/][img]http://s18.postimage.org/xp4rtmfp1/P040213_13_34_01.jpg[/img][/url] Only socketed chip is ULA which …
Yes the lower 16K removed gives me something similar.< ...Multiface +3 AdviceHi, New to the forum after resurrecting my +3 and looking for a bit of advice on the Multiface 3 please. Quite simply is it worth investing in for…
... will be loaded to bottom 16k memory.
128K games ...
