This hobby project aims at designing and constructing a fully functional 16-bit computer and running usable software on it.
The computer’s name is BYTEC/16 and it was designed and built by me from scratch, using mostly low-level logic components (TTL). It does not use any commercial off-the-shelf CPU like 6502 or 680×0 but an original CPU design. Here are few technical details:
- original 16-bit CPU design running at 4.09 MHz (support for faults and interrupts, protected and user mode, instruction set with 256 opcodes)
- up to 4MB memory (with MMU, processes see 128kB memory divided in 64kB code and 64kB data segments)
- two serial ports
- IDE interface and RTC
The computer does not have a graphics adapter nor a keyboard and I connect to it from a PC using a serial connection.
Currently work is in progress primarily on software:
- BYTEC is running a custom Monitor/OS program able to do basic diagnostics, provide a simple shell and loading and executing programs over serial port
- advanced programmer toolchain exists (hosted on a PC for cross development) including an assembler, linker and ANSI C compiler (a port of LCC)
This website is used as a project diary (blog) and a repository of all project related documents, schematics and specs.
The construction of BYTEC/16 has been mostly completed, save for any bugs I may still find. The CPU was built on seven 100mm by 160mm boards stacked and connected with standard Arduino-type shield connectors. It is enclosed in an 19-inch rack enclosure and now sits in my desk exposing its peripheral interfaces on the front. The peripherals include a memory card, IDE interface card and serial ports card.
For a long time BYTEC’s only built unit was a wire wrapped prototype which I used to validate my designs. It did not have any enclosure and occupied most of my desk whenever I wanted to power it up and do some project work. You can see it below with early versions of peripherals – an RS-232 card (still wire wrapped), and and IDE interface with an old hard drive connected to it. Everything was hooked up to an old ATX power supply and an old laptop. This looks like an unmanageable tangle of wires but I was somehow able to find my way.
This is a screenshot of a terminal emulator on a PC connecting to BYTEC/16’s Monitor/OS program over a serial connection.
My name is Dawid. I am Polish, but I live in Bonn, Germany. If you wish to contact me, use the email address below.