DIY 8-Bit Z80 Single Board Computer Ivan Farafontov 2022-07-24 | This is an awesome Z80 Single Board Computer project I finished last year. It went through a couple of revisions over a few years, this is the final one. It has Zilog Z80 10Mhz CPU, 8Kb ROM, 8Kb VRAM, 48Kb RAM (64Kb total), 2 serial ports (Zilog SIO IC), 2 Atari-compatible joystick ports (first Zilog PIO IC), AY-3 sound generator by General Instruments, built-in mechanical keyboard (second Zilog PIO IC) and Zilog CTC clock chip servicing blanking video interrupts. This is Sinclair ZX Spectrum personal computer reimagined - it's what I wanted it to be.It has one demo game written for it - Boulder Dash clone, one application - graphics tile editor. And it has small debug monitor program built in the ROM. I plan to make BASIC interpreter for it and assembly language development environment after I finish making Window/Linux/Mac SDL-based emulator.Project web page: solisted.net/projects/z80-single-board-computerSchematics, gerbers and CAD files: github.com/solisted/z80sbcEmulator for Windows: solisted.net/projects/z80-sbc-emulatorHigh quality manufactured PCBs of the mainboard and keyboard for sale: ebay.co.uk/itm/165783862203It is very easy to build it yourself. No sophistication required to do it, it's completely made of through-hole components, very easy to solder at home. CPLD ICs are also very easy to program with inexpensive tools. I will make a separate video on how to work with Atmel CPLDs used in this project.
Prototyping 8-bit computers Ivan Farafontov 2021-10-29 | In this video, I want to share with you special kind of prototyping boards I made while experimenting with 8-bit CPUs. These boards are aimed to replace breadboard prototyping to increase density and signal integrity of a single board computer prototype. Towards the end of the video, you will see one of my computer prototypes made with these boards.
DIY graphics card with VGA output Ivan Farafontov 2021-09-30 | This is a project I started my electronics hobby with (not counting various blinking LED's connected to a microcontroller :). After reading some article, I was very excited with the possibility of generating video signals using digital logic IC's. FPGA's were very difficult to understand and expensive for me back then, so I decided to try it with the CPLD technology. When the first prototype was built, I realized that displaying static image is boring and I need to make it moving. To my big surprise, after browsing DigiKey and Mouser catalogs, I found that Zilog is still producing Z80 CPU in DIP packages. Shortly after that, I started building Z80 computer around this graphics card :) I will demo this computer project in one of my following videos. Stay tuned!Project schematics and gerbers: github.com/solisted/atmel-vga
