Search found 337 matches

by McKlaud
Sun Apr 08, 2018 11:44 pm
Forum: Hardware
Topic: 28C64 in 2364 socket (28 pin to 26 pin)
Replies: 10
Views: 5421

Re: 28C64 in 2364 socket (28 pin to 26 pin)

Nice :)

I've done something similar for SMD EEPROM chips. See below:

Image

The project is public on OSHPark, there: https://oshpark.com/shared_projects/ArG7JDff
by McKlaud
Tue Apr 03, 2018 4:59 pm
Forum: Development
Topic: ZX Printer Belt
Replies: 139
Views: 85814

Re: ZX Printer Belt

Looks good! Unfortunately I live on "the wrong" side of the pond. :geek:
by McKlaud
Fri Mar 30, 2018 3:01 pm
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 238
Views: 123563

Re: ZX81 ULA-in-a-CPLD

Well :mrgreen: your scope has been out of calibration for 14+ years ;) So, results as expected :mrgreen: don't blame ULA :mrgreen:

Anyway I decided to use Schmitt-triggers and gave up with the noise. It is as it is.
by McKlaud
Thu Mar 29, 2018 5:21 pm
Forum: Development
Topic: ZX Printer Belt
Replies: 139
Views: 85814

Re: ZX Printer Belt

Please see the attached, I hope it would help.
by McKlaud
Wed Mar 28, 2018 10:56 pm
Forum: Development
Topic: ZX Printer Belt
Replies: 139
Views: 85814

Re: ZX Printer Belt

I am looking for a volunteer who can do three of such belts for me :mrgreen:
by McKlaud
Wed Mar 28, 2018 10:46 pm
Forum: Development
Topic: ZX Printer Belt
Replies: 139
Views: 85814

Re: ZX Printer Belt

@svid123: very impressive.
by McKlaud
Wed Mar 28, 2018 6:37 pm
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 238
Views: 123563

Re: ZX81 ULA-in-a-CPLD

BarryN wrote: Wed Mar 28, 2018 6:27 pm Is slow mode working yet?
In my ULA, still work in progress. Unfortunately I had to pack my toys and locked them up for a few weeks. :(

@Andy: Are spikes in your case similar to these in red circlers in the attached picture?
by McKlaud
Tue Mar 27, 2018 11:43 pm
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 238
Views: 123563

Re: ZX81 ULA-in-a-CPLD

"Dead Cockroach Mark II" :lol:
by McKlaud
Tue Mar 27, 2018 9:46 pm
Forum: Hardware
Topic: T/S1000 Turbo Switch
Replies: 5
Views: 3016

Re: T/S1000 Turbo Switch

As Andy said, switching between 60Hz and 50Hz ... in real terms the speed increase up to 30% in SLOW mode. In the FAST mode it does not make any difference at all.

If you are looking for a real speed-up solution, go for the modification called "noWAIT".
by McKlaud
Tue Mar 27, 2018 8:39 am
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 238
Views: 123563

Re: ZX81 ULA-in-a-CPLD

Hi Andy, I've faced the same issue when I built the resistor network with the 1.2V bias. It worked well when isolated on a breadboard, but when I plugged the ULA in to the Zeddy's PCB I started reading 2.4-2.5V. Odd. So I gave up with it and just tried to load anything directly with the circuit as i...