Archive for the 'retrocomputing' Category

Repairing an Acorn A3000

The Acorn Archimedes A3000 came out in 1989. My vague recollection of the era is that the Amiga 500 was really popular around then, and even though the A3000 was a lot more powerful, it was in a price bracket that made it a lot more expensive. I probably didn’t know how much more powerful […]

Amstrad CPC ROM emulation using an STM32F4 – Part 2

So in part 1 (Amstrad CPC ROM emulation using an STM32F4) the code I had for emulating a ROM (and some IO) with a cheap STM32F4 board for the Amstrad CPC 464 ran in a continuous polling loop. The code just watched  _ROMEN and _IORQ going high and low, and acted appropriately. The (sort of […]

Amstrad CPC ROM emulation using an STM32F4

UPDATE: There is a ‘part 2‘ to this article. In that I use interrupts, instead of the polling technique shown below So, in emulating a hardware ROM in real time with an STM32F4 I hooked up a cheap US$10 STM32F4 board to my Acorn Electron to act as both a sideways ROM board and a sort of […]

Emulating a hardware ROM in real time with an STM32F4

I remember reading dhole’s  Emulating a GameBoy Cartridge with an STM32F4 some time ago thinking that it had a lot of applications with respect to old computers. In that article  a STM32F4 microcontroller  ‘pretends to be a ROM chip for a gameboy’. At the start of a bus cycle, an interrupt is triggered in the […]

Using TZXDuino to play UEF tape images

TZXDuino is a cool Arduino project that is basically a standalone hardware cassette audio playback unit for old computers. You hook up an Arduino, a microSD card adapter, an I2C LCD display and 5 buttons. Load a microSD with lots of game dumps, and hook that up to the audio input of your ZX Spectrum […]

BBC Micro Model B

I recently bought a BBC Micro Model B. It sold ‘as is’ and I had no idea if it worked. The case was very yellow. It came with a  5 1/4″ drive, cassette player, several books and original versions of Elite on disk and cassette. It did not work, and ended up having a number […]

Amiga Kickstart Switcher with no switches

A while back I burnt some 27C160 EPROMs for some of my Amigas. This allows you to have 4 kickstarts in an A500 or A600. Normally you would wire up two switches to the upper address lines of the EPROM to select the 4 images. But I thought there must be some way of selecting […]

Amstrad CPC-464 and broken sound chips

So I was pretty chuffed with setting up my Frankenstrad using just a CPC-464 motherboard and a homebrew keyboard. However, as luck would have it, a few weeks later, the local auction site had a couple of real CPC-464’s for sale … so I bought one.


So I bought the motherboard out of an Amstrad CPC-464. This was like my Oric Atmos rationalisation . It’s cheaper to just buy the motherboard of some of these old computers, rather than the whole computer (especially when I add in postage from the UK to NZ). And I am more into these old computers […]

SIO2SD with an Atmega328p

So, I have a SIO2Arduino setup hooked up to my Atari 800XL as a virtual floppy drive image thingee. It works pretty well and was really easy to make; one Arduino Uno plus one Arduino SD card adapter plus a few wires. Another popular one is SIO2SD. You can buy prebuilt SIO2SDs  from Lotharek , […]