ZX Spectrum Expansion System Recreated (IF1 and Microdrive hardware emulator)
Posted: Fri Jul 21, 2023 9:52 am
This is my latest hardware project, a recreation of the ZX Spectrum Expansion System from 1984.
The original expansion system bought you a Microdrive and the Interface 1 required to connect it to the Spectrum. My system is a single box which provides 8 virtual Microdrives with no Interface 1 required. The virtual Microdrives use MDR-format cartridge images delivered from a micro SD card.
The system is, to my knowledge, completely compatible with all Microdrive-supporting software from the 1980s. There are no workarounds, ROM hacks or limitations. All my operational design cues were taken from the way the original Microdrive works, so cartridges are inserted and ejected, write protect behaves the same way as the original and so on. Read and write operations (e.g. LOAD* and SAVE*) all work as expected. Use of the MDR format makes the virtual cartridges compatible and interoperational with emulators which support Microdrives.
I made a short demonstration video:
As ever with my work, it's open source and open design, licenced under the GPL. There's lots more information on my website, and the sources are on Github.
The original expansion system bought you a Microdrive and the Interface 1 required to connect it to the Spectrum. My system is a single box which provides 8 virtual Microdrives with no Interface 1 required. The virtual Microdrives use MDR-format cartridge images delivered from a micro SD card.
The system is, to my knowledge, completely compatible with all Microdrive-supporting software from the 1980s. There are no workarounds, ROM hacks or limitations. All my operational design cues were taken from the way the original Microdrive works, so cartridges are inserted and ejected, write protect behaves the same way as the original and so on. Read and write operations (e.g. LOAD* and SAVE*) all work as expected. Use of the MDR format makes the virtual cartridges compatible and interoperational with emulators which support Microdrives.
I made a short demonstration video:
As ever with my work, it's open source and open design, licenced under the GPL. There's lots more information on my website, and the sources are on Github.