Big box of PCB’s

January 30, 2020

This week saw the arrival of another big box of PCB’s. A lot of PCB’s. Some old but many new.

Arriving where some new stock of RC2014 prototype board, prototype plus boards and extender boards which I sell on Tindie.

Also in the box where some new board designs. No new RC2014 PCB’s this time but some boards for the ZX Spectrum and Commodore 64 computers. I’ll share more details of these in the coming days and weeks.

Time to break out the soldering iron đŸ™‚

Here’s my Tindies store.


ZX Spectrum Projects – HD Video output

October 28, 2019

I’ve neglected my retro computer collection for a while now, so recently I’ve been dusting off my collection, starting with the ZX Spectrum to start some new projects with them. Whilst I have a few that need repairing I quickly got distracted into wanting to make a cool project for them.

Getting the Speccy to work with modern TV’s is becoming more of a problem. I’ve made composite video modifications to my Speccys in the past, I even made a small PCB that fits into space where the existing video modulator sits. But I want to see if HD / High Definition video was possible. By HD video I mean either VGA, DVI, DisplayPort or HDMI.

A quick web search found me Victor Trucco’s TK Pie. This is an interesting way of using a Raspberry Pi Zero to provide a High Definition (HDMI) video interface to the Speccy. It uses a mix of external hardware (CPLD) and the processing power of a Raspberry Pi Zero to capture writes to the Speccy’s video RAM and convert the pixel data into HD video via the Pi’s HDMI. There’s a similar project for the BBC Micro called RGDtoHDMI.

Here’s a link Victor’s web site and TK-Pie source code files

There are couple of useful reviews of TK Pie by GozdniJezek, Building TK-Pie by Victor Trucco

and martin@8bity, HDMI output for Sinclair ZX Spectrum – TK-Pie

Some more searching found me the next two devices. They don’t seem to be DIY projects but I thought they looked interesting.
Ben Versteeg at ByteDelight has ZX-HD: The story of the ZX-HD

and also Goran Radan with his ZX-VGA-JOY


Apple II Prototyping PCB’s

June 29, 2018

I recently came into possession of a Apple IIe (an enhanced Apple II from the early 80’s) and decided to build a few PCB’s to help get this old warhorse back up in running. The first board  designed was an extender card for the Apples expansion card to make testing and fault finding them a little easier. The second PCB was a prototyping board to allow me to build up various test circuits.

 

Both will be available on Tindie soon


An update to “List of Homebrew Video Games Consoles”

January 31, 2011

I’ve neglected my list of homebrew video game consoles, so here’s a update:

  • www.xcores.orgMy friend Yvo’s site related to the awesome Xmos chip.
  • mikronauts.comPropCade is a self-contained and affordable Propeller platform for emulating old computers (Z80, 6809, etc) and old game consoles.
  • www.retrode.orgNot a console as such but a handy way feeding games to your SNES or Mega Drive / Genesis emulator from your original cartridges.
  • www.4dsystems.com.auPoGa, a Portable Game Development console looking a lot like a SNES controller.
  • www.chameleon-dev.comChameleon PIC 16-Bit and the Chameleon AVR 8-Bit are yet another Propeller based systems this time with the addition of a standard Microchip PIC or Atmel AVR microcontroller.
  • www.fpgaarcade.comA site dedicate to recreating gaming hardware from the past in modern programmable FPGA devices.
  • www.lucidscience.comA beautifully documented insight to designing and building your own classic console
  • www.microvga.coma design offering a low-cost Microcontroller to VGA interface
  • www.ladyada.netA new system from LadyAda offering a 320×240 TFT color display with resistive touch screen.
  • rossum.posterous.comRBox: A diy 32 bit game console for the price of a latte
  • www.linusakesson.net linusakesson “craft”

the original list is still here:


The ZX Spectrum ULA: How to design a microcomputer

December 29, 2010

I’ve been following Chris Smith’s zxdesign.info web site for a number of years. His redesign of a ZX Spectrum ULA using only logic IC’s was an awesome achievement.

In addition he’s wrote a wonderful account “The ZX Spectrum ULA: How to design a microcomputer” on the forerunner of programmable logic – the Uncommitted Logic Array (ULA). I was lucky enough to get his book as an early Christmas present and I found it a great read.