So as promised I spent a bit of the bank holiday weekend hacking on the FPGA Spectrum to fix a few bugs.  In the end I got carried away and finished up with a full implementation of the 128K Spectrum +2A running ResiDOS and loading emulator images from an SD card.  It’s still not cycle [...]

As promised, some more detailed design notes for my BBC B design are now available. Planning to revisit the Spectrum design next for some bug fixes, as it is clear there is still quite a bit of interest in that.

I added a video of the FPGA BBC in action, shot straight off the TV. You can see the MMBEEB ROM extensions providing access to multiple disk images on the SD card, then some messing about on Chuckie Egg and Boffin.

It’s been a while since the Spectrum project and, although there is still work left to do on that, I eventually gave in and did another great British computer from my childhood – the BBC B.  Getting this machine up and running has been an interesting job given its complexity.  For something that first came out [...]

Last week I was made aware of this post on RS DesignSpark about a project, currently in the very early planning stage, to build a Sinclair Spectrum on an FPGA.  As it happens I have a similar project well under way, and I have promised to write it up… Several years ago I implemented most [...]

I had a dead motherboard that had been kicking around for a while after a failed BIOS update.  The flash part on there was the Winbond W39V040B, which is 3.3V only and has an LPC interface.  The device programmer I have access to wouldn’t touch it, so I put together some simple AVR code to [...]

I’ve had a few controllerless QVGA (320×240) mono LCD modules lying around for a while looking for some use.  These are fairly easy to get going with a low-end microcontroller using an external controller IC like the SED1335, but that’s another story.  I’d been thinking about doing some sort of integrated home automation project, and [...]