Greetings from Palo Alto, California

Introduce yourself to your fellow forum members - what was your journey into the Sinclair world?
Post Reply
User avatar
swetland
Posts: 20
Joined: Mon Jul 25, 2022 12:13 am
Location: Palo Alto, CA
Contact:

Greetings from Palo Alto, California

Post by swetland »

Hi!

I mostly grew up with a C64 that I learned BASIC and 6502 assembly on, but two years before our family got that machine, my father spent several evenings soldering together a MicroAce (unlicensed ZX80 clone) on our kitchen table and eventually hooked it up to a small B&W TV on UHF33 and we witnessed the wonder of 1KB of BASIC, the inverse K prompt, membrane keyboard, and fussy cassette interface. At five years old I was a little young to really appreciate the machine but it sparked an interest in computing that lead to a career in Operating System Engineering (I share some blame for later BeOS releases, Danger's HiptopOS, and Android's lower level architecture).

Some 40 years after seeing that MicroAce go from a pile of parts and a bare PCB to a Computer, I stumbled over @mahjonng's ZX81+38 project which re-imagines the ZX81 in the all-discrete 7400 series logic style of the ZX80 (and MicroAce): viewtopic.php?f=7&t=3357

It looked like a lot of fun to build and I figured it'd be fun to throw together a mechanical keyboard and custom enclosure for the new machine, which is currently looking a bit like this:

Image
(holes in the case bottom are for faster prototype printing, will not be present in the final build)

I've got an order out to WASDkeyboards for a set of custom keycaps which should look like:
Image

And parts and PCBs are on their way back from digikey and JLCPCB for what I'm calling "ZX PICO IO" -- a multipurpose IO peripheral based around the RP2040 MCU, some level shifters, and some address decode logic -- hoping to provide a "serial port" and "fast tape port" to get data on and off the machine via USB, and might look into implementing an alternate VGA or HDMI display peripheral (character graphics + bitmap + sprites perhaps), depending how much time I end up sinking into the project.

Image

There are more pictures and commentary over here in this Twitter "Moment" where I've been collecting my tweets about the project:
https://twitter.com/i/events/1549999559610228736

Meanwhile I've been having a lot of fun exploring the wealth of software that's been written for the machine, marveling at WRX Hi Res mode (back in 1981 it had not yet been invented (discovered?)), and reading magazines and articles from the 80s that have been preserved in various online archives. Amazing how much has been achieved with such a limited little platform.
User avatar
mrtinb
Posts: 1906
Joined: Fri Nov 06, 2015 5:44 pm
Location: Denmark
Contact:

Re: Greetings from Palo Alto, California

Post by mrtinb »

If you want VGA output, you simply connect a ESP32 with the Wespi-V firmware. With this firmware you can also LOAD and SAVE files on ESP32’s internal web server.

viewtopic.php?t=4155
Martin
https://zx.rtin.be
ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
User avatar
swetland
Posts: 20
Joined: Mon Jul 25, 2022 12:13 am
Location: Palo Alto, CA
Contact:

Re: Greetings from Palo Alto, California

Post by swetland »

Oh that is very slick, using the tape interface and being able to bootstrap from emulation of tape audio. My approach is definitely more involved and I figured I'd eventually end up modifying the ROM to support it transparently. Still going to finish building up these IO interfaces, since I've already ordered PCBs and parts and building it all is part of the fun, but neat to see other approaches.

As far as display goes, I was planning on providing a full alternate display (which wouldn't use the composite video path at all, and thus allow the Z80 to run full speed all the time) which wouldn't be backward compatible but would allow for some interesting experiments (including color, sprite graphics, etc).
jdfan1000
Posts: 81
Joined: Tue Aug 02, 2016 8:06 pm
Location: Buffalo, NY
Contact:

Re: Greetings from Palo Alto, California

Post by jdfan1000 »

Hi!

That’s a fantastic machine you have. You may want to join the TS2068 groups.io list (name inherited from a Yahoo group but we cover all TS).
https://groups.io/g/TS2068/

Also, we meet 2x month on Zoom; our schedule is here:
https://www.timexsinclair.com/about/community/

Best,
David
My archive.org collection, containing many Timex/Sinclair related publications.

TimexSinclair.com, my website about Sinclair computers in the US.
User avatar
1024MAK
Posts: 5101
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: Greetings from Palo Alto, California

Post by 1024MAK »

Hello and welcome to our forum swetland!

:D :D :D

I hope you enjoy this forum :D

Please do keep up updated with your hardware developments ;)

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
User avatar
swetland
Posts: 20
Joined: Mon Jul 25, 2022 12:13 am
Location: Palo Alto, CA
Contact:

Re: Greetings from Palo Alto, California

Post by swetland »

The custom keycaps I ordered from WASDkeyboards arrived today and the machine is looking much more complete now:

Image

I need to finish up the case design (rear cover, opening for expansion port).
User avatar
code-surfer-dev
Posts: 13
Joined: Sun Jan 02, 2022 4:20 pm
Location: Niskayuna, NY
Contact:

Re: Greetings from Palo Alto, California

Post by code-surfer-dev »

WOW! Really nice work swetland!

I have been tinkering around with a prototype mechanical keyboard too, as well as other mods/updates, and posting on my blog:

https://blog.codesurfer.dev


I would love to chit chat with you some day about your work.
Lardo Boffin
Posts: 2160
Joined: Sat Nov 26, 2016 2:42 am

Re: Greetings from Palo Alto, California

Post by Lardo Boffin »

The custom key caps look really nice. 8-)
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
Post Reply