In this post, I create an 8-bit ISA board that can be used either as expanded memory (EMS) or as a flash disk: Motivation The motivation for this project came from a Boca Start Card that I owned back in the late 80s or early 90s. The Boca Start Card was one of the first …
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PS2-TTLSerial Adapter for RC2014 and MIDI
In this post, I build a PS/2 Keyboard to TTLSerial Adapter Motivation The original reason for this project is that I wanted to build a standalone RC2014 with keyboard and display. There is an official RC2014 serial keyboard, but I find it a little inconvenient for my big fingers and poor eyesight. I have plenty …
Read MoreRaspberry Pi Midi Hat / Building a Raspberry Pi Midi Jukebox
In this post, I build a Midi Hat and Jukebox using the Raspberry Pi Motivation I picked up a Roland SC-55 to use with my retrocomputer setup recently, and I figured it would be cool to turn the thing into a standalone midi jukebox, so that no “computer” is required. I also figured this would …
Read MoreVintage MIDI: Roland MT-32, Roland SC-55, HardMPU, and an Xi 8088
In this post, I build a HardMPU board and use it to add midi capability to my Xi 8088 home built PC Background Midi stands for “music instrument digital interface”, and is a relatively simple protocol for controlling musical instruments. A midi controller can be a computer, or a keyboard, a sequencer, or any other …
Read MoreCTS256A-AL2 Text-To-Speech Board
In this post, I buld a board that uses the CTS256A-AL2 text to speech and SP0256A-AL2 speech synthesizer chips: Why? “Why? ” seems like a good question to ask. I’ve been working with vintage speech synthesizer ICs lately, and you see the CTS256A-AL2 appear on eBay from time to time. The CSS256A-AL2 is not a …
Read MoreISA Speech Synthesizer board using SP0256A-AL2
I’ve done a few speech synthesizer posts already using the SP0256A-AL2 chip by general instruments. We’re at a relatively fortunate time in that there are some authentic functional chips available on eBay. As always, make sure you do your research and make sure you’re buying from a reputable seller, or at least someone with a …
Read MoreZ80 Retrocomputing 18 – Z180 CPU Board for RC2014
In this video, I design and build a Z180 CPU Board for the RC2014 Motivation I wanted to try a CPU that runs at faster clock speeds and has more built-in peripherals than the Z80. More built in peripherals means less external boards needed for mundane features, and more room in the backplane for “interesting …
Read MoreZ80 Retrocomputing 17: Enhanced Z80 CPU Board for RC2014
I set out to build a fancier CPU board: Design I wanted the CPU board to have the following features: on-board oscillator, so that a separate clock board is not necessary power-on reset circuit reset header for external reset switch status LEDs for common signals such as RD, WR, MREQ, IOREQ, M1, and HALT Below …
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