Search found 365 matches

by RetroTechie
Fri Jul 20, 2018 10:33 pm
Forum: Sinclair Misc
Topic: Ferranti ULA doc may be of interest
Replies: 12
Views: 3494

Re: Ferranti ULA doc may be of interest

Pretty useless in practical sense. But nice reading material anyway. :D now then if any is clever enough to decap a ULA and photograph the final layer, it would be possible to reconstruct the exact logic hiding inside the little vlack chip :mrgreen: Getting at the bare IC die isn't the hard part... ...
by RetroTechie
Thu Jul 05, 2018 10:21 pm
Forum: Sinclair Misc
Topic: Z80 CPU part number cross reference
Replies: 1
Views: 613

Z80 CPU part number cross reference

Hello all, I've compiled an overview that (apart from speed and package) includes all Z80 CPU's you're likely to come across. Including 100% plug-in compatibles, NOT including almost-compatibles-with-a-few-added-pins, or pin-compatible-with-internal-additions (read: that are not a 100% functional eq...
by RetroTechie
Thu Jul 05, 2018 9:22 pm
Forum: SALES
Topic: ZX81 ULA
Replies: 70
Views: 16057

Re: ZX81 ULA

For a novice it's impossible to remove an IC without a desolder gun. Nope. Practice! Plain iron & solder pump go a long way. I rarely damage IC OR board. But it really takes practice to remove IC's without damaging a board. If that practice is lacking, safest method is to cut pins (and take destroy...
by RetroTechie
Wed Jun 27, 2018 7:18 pm
Forum: Software
Topic: ZX81 Youtube videos
Replies: 2
Views: 1606

Re: ZX81 Youtube videos

Look closer - @ any point there's like 3 or more gliders visible in that video most of the time. :shock:

Very nice video indeed!
by RetroTechie
Wed Jun 27, 2018 7:08 pm
Forum: Welcome Area
Topic: Hello
Replies: 4
Views: 1179

Re: Hello

Welcome, Gar r y! ;) For fixing your ZX81, what tools you have available? Scope or even a simple logic probe would be very helpful. Any other ZX81's in your possession that you could swap parts with? Usually ZX81's are easy to fix, with 2 exceptions: ULA itself. If that's dead (or its video output b...
by RetroTechie
Wed Jun 13, 2018 9:38 pm
Forum: ZX Spectrum Lounge
Topic: Any WoS admins on here?
Replies: 5
Views: 3100

Re: Any WoS admins on here?

Seems to be fixed now, I was able to log in again on WoS. Thank you both Mark & Lee for the help! :D

Still think it was a problem with WoS site though, as I've not had similar issues elsewhere. Let's hope no other WoS are affected by this (whatever it was).
by RetroTechie
Tue Jun 12, 2018 9:36 pm
Forum: ZX Spectrum Lounge
Topic: Any WoS admins on here?
Replies: 5
Views: 3100

Any WoS admins on here?

I'm in need of a wee bit of assistance... ;) Have been locked out of my World of Spectrum account for a while. Forgot how it happened, iirc logging in didn't work any more after updating my e-mail address. Since I don't post there often & was busy with other things anyway, went into read-only mode f...
by RetroTechie
Fri May 25, 2018 4:07 pm
Forum: SALES
Topic: SINCLAIR ZX SPECTRUM + 128K TOASTRACK RETRO VINTAGE COMPUTER
Replies: 3
Views: 1169

Re: SINCLAIR ZX SPECTRUM + 128K TOASTRACK RETRO VINTAGE COMPUTER

Agree on this one... :( I propose that users who only (or almost exclusively) use their account to post in the Sales section, be treated as spammers. And thus removed / blocked / banned / whatever. Above user would be a good example, just check this user's previous posts to see what I mean. Such use...
by RetroTechie
Sat May 19, 2018 12:02 am
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 233
Views: 40670

Re: ZX81 ULA-in-a-CPLD

what ram would i be enabling ? A 32K*8 SRAM used in a simple internal 16K RAM mod? Say, enabled in 2000-9FFFh range. Or mirrored all over the 64K address space except the lower 8KB occupied by the ROM? (that would also be nice when using a 128K*8 SRAM to fill the entire 2000-FFFFh range with unique...
by RetroTechie
Fri May 18, 2018 9:56 pm
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 233
Views: 40670

Re: ZX81 ULA-in-a-CPLD

Great progress Andy! Looking good! :D oh my :geek: the link in the middle is mighty close to touching the case ... the easiest thing would be to fit a right angle header. (might have to bend it up slightly :? ) Personal opinion: put feature jumper(s) on a side end of the board. One pin solders to to...