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Another badly behaved RAM upgradeI have a 48K issue 4A board (yellow it is) that was a 48K machine from new, but only reports 16K working with the Sinclair ZX Test ROM in an Int2. H…
... swapped in a known good ULA chip just coz its an ... -
Suggestions for Mr. Rich MellorRich, is there a chance any of these things could be available from you in a near future? -AY interface for 16K/48K Spectrums -PS/2 keyboard interfa…
... fix on +3, memory replacement, ula replacement, hardware fix to add ... -
Sinclair Spectrum ULA BookAnnounced in the Hardware forum, but might be interesting to others: [url]http://www.worldofspectrum.org/forums/showthread.php?p=324213[/url] Regar…
Announced in the Hardware forum, but might be interesting to others:
[url]http://www.worldofspectrum.org/forums/showthread.php?p=324213[/url]
Regards
Chris -
Cro S2008Hi everybody!!! I hope this is right thread? :-) I want to share with you my new project. I call it ?S2008?? The idea was to build Spectrum48K clo…
... good staff already built in? ULA, Z80, LM1889 must stay in ... -
Dead microdrive advice plsHi, I recently got a box of bits off ebay, and one of the items is a dead microdrive. Now assuming the motor inside it works (I havnt tried putting…
... -solder incase I fry the ULA) what are the likely causes ... -
Help with faulty +2ahi everyone I'm Nuno from Portugal I think I made poopoo with a 128k +2a motherboard I had spare for testing purposes This motherboard has always …
... to 48k I think the ULA is working no?
the ... ula on amstrads is that square ... -
R.I.P. spectrum 48kRecently one of my 48k rubber key (issue 4) machine bit the dust the other day when I tried to power it on. When powering it on, it gave a weird 'bee…
... Res?arch r$...
The ULA gets very hot.
ULA ferranti #7, all new electrolytic ... some custom fit heatsinks for ULA, Z80, etc...
I seem ... -
SRAM replacement for lower 16KSome time ago I wondered if it were possible to replace the lower 16K RAM of a 16K/48K Spectrum with a single SRAM chip. You know, those pesky 4116 D…
... issue 4B (rubber keys)
[*]ULA inside is of type 6C001E ... case with other issue boards, ULA versions, or SRAM types. Right ... -
Component count/modern replacementsThere is a thread/project for replacing the old memory with simms There is also the ULA replacement. There's DEATH's composite replacement. What els…
...
There is also the ULA replacement.
There's DEATH ... -
Yay. Found an issue 1!I've had a Speccy sitting about the house for a while, unused as it only ran as a 16k (a sticker seal on the casing suggested either a 48k upgrade or…
... 1 16k (with the little ULA daughterboard).
Thing is ... -
+2 datacorder noise eliminationHello :-) I have recently bought a gray +2, and as expected, it is plagued with the "datacorder noise in sound output" problem. I have found a few …
... by motor reaching and destroying ULA if the whole datacorder circuitry ... is wired straight into the ULA without any buffering and a ... the possibility of killing the ULA if the voltage applied exceeds ... -
issue 6a faultyHi All I got issue 6a pcb from ebay with status faulty pcb had bad voltages when I power up I changed tr4 ztx650 and all voltages got back on ic6 I h…
... 74ls04 (old one working too), ula working fine - I have 2 ... -
Sprinter 2000A while ago I bought the Sprinter 2000 from the now defunct St. Petersburg-based company Piters Plus. It is one of the last five or so of the 120 or …
... IDE disk support.
The ULA is kept inside an FPGA ... -
interface1discipleanyone manage to virtually connect two emulators running on the same machine? could zx spin be modified to replay two rzx files simultaneously? any o…
... an lcd screen - think the ula snow comes thru ? -
DRAM without powerSomething interesting I noticed last night, after making a bad Spectranet ROM image which crashed the machine... Looking at the image on the screen,…
... ago, csmith noted that the ULA sometimes exceeds the datasheet's ... -
issue 4s for reapirHi All, This time I have issue 4s for repair :) Here is few screen shots and small movie after boot. [url]http://forest.no-ip.org/issue4s/[/url] I kn…
... /[/url]
I know only ula working fine and have good ... -
How feasible is it to add a second CPU to the ZX Spectrum?Today with IDE, and USB, and TCP/IP and other wonderful technologies arriving on the ZX Spectrum, I'm beginning to wonder if we'll run out of CPU tim…
... when neither CPU0 nor the ULA are using it. This ensures ... -
Issue One 'Dead Cockroach' chipI recently got hold of an Issue One spectrum, and I started wondering: is the dead cockroach chip required due to a flaw on the PCB, or is it really …
... really a flaw in the ULA chip itself?
Also ... -
2 new FPGA based clone from russiaFirst of all I wanna introduce you to the [B]ZX Evo[/B] by NedoPC -> [URL="http://www.nedopc.com/zxevo/zxevo.php"]http://www.nedopc.com/zxevo/zxevo.p…
... an FPGA instead of an ULA, so you can make it ... -
Spectrum Serial Numbers Wanted!![b]This post updated Sept. 26, 2013[/b] As far as I know, the serial numbering system for the Spectrum has never been fully worked out. For the p…
... various components such as modualtor, ULA, Z80, memory etc.
... [CODE]Serial : [xxxxxxxxxxxx] [ colour ]
ULA : [5C012E 5C112E 6C001E-6 6C001E ... Serial : 001-62176 white
ULA : 5C102E 8217
CPU : ... -
Where's the border line between a Spectrum and something else?I mean: there are purists out there that consider that anything that is not a true Sinclair Spectrum, with a true Z80 and a true ULA, and at most, 48…
... true Z80 and a true ULA, and at most, 48K RAM ... -
General question about electronics I guess... (128k +2a)[Short question] When I very slightly put my finger on top IC15 on my +2A the TV picture becomes crazy and the spectrum acts if it just resets I don…
... is great, ROMS are great, ULA must be good due to ... -
RGB to VGA convertor for ZX (clones)[img]http://s44.radikal.ru/i106/0908/1a/28c90d0ca25b.jpg[/img] [img]http://s15.radikal.ru/i188/0908/f2/c1d66b5f6d4f.jpg[/img] It's GOOGLE translatio…
... ,HSYNC,VSYNC,+5V,GND,14MHz (ula clock). Output is VGA 50 ... or CSYNC only)
- faster ULA clock than 14MHz (ZX128 use ... calculate pixel clock from original ula clock):
[img]http://velesoft ... -
Specdrum SyncroI'm having trouble syncing my (revision 4b)48k specdrum. The sync pulses sent out of the MIC socket are low, barely +50db, and isn't powerful enough…
... />
Anyway, is this a ULA problem, if I change the ... to pin 28 of the ULA will I get better performance ... -
Spectrum dead: 8 vertical bars in alternating colorsI have been soldering on this basterd for a long time now. All IC's now have sockets (except the LM1889). I swapped all 4116's by types that are 100%…
... . Power is 100% ok. Swapped ULA, Z80 and ROM for 100 ... -
Horror repair story...Today the (new) +3 had a strange issue: keys 6,y,h,n and 8,i,k were not working. Also, the internal drive sometimes was not 'visible' from the Loader…
... was near that spot... the ULA!!
I took my 15x ... inspecting the pins of the ULA...
I really freaked ... of one side of the ULA were
loose... WTF! I ... *ck these pins of the ULA were auto-de-soldered ??
Repair options for my own dear old Spectrum 48k?Hello all, This is my first post to this wonderful forum, which is part of a truly great website! My name is Arnold, and I live in Utrecht, The Nethe…
... in a working Spectrum). The ULA gets quite hot in the ...Some ever noticed that +2A/+3 halts Z80 using WAIT?I mean: Anyone ever noticed that the +2A/+3 halts the Z80 using WAIT? All documentation I've read about contention state that the ULA halts the Z80 …
... contention state that the ULA halts the Z80 by ... with the surface mount ULA) uses WAIT to halt ... period, the time that ULA is reading video data. ... 8MHz signal generated by the ULA for the TEA2000. Should ... , internal timmings at the ULA, which is the responsible ...An idea for a possible(?) new interfaceDue to the Spectrum's processor speed and the way the ULA works, there are a couple things (among others) that are difficult to do: -Gigascreen or a…
... speed and the way the ULA works, there are a couple ...
