APOLLO181 - a homemade 4-bit TTL Processor
Опять же - схемотехнику сильно упрощает применение 74181 Arithmetic and Logic Unit.Gianluca.G. wrote:APOLLO181 is running today at 2.5 MHz on a 12x12 inches single perfboard.
The design is based on the famous 74181 chip that is a TTL Arithmetic and Logic Unit.
APOLLO181 uses 8-bit instruction word and 8-bit address bus which can access 256 Byte of user program memory. The reason we classify it a 4-bit processor is that the internal registers and the arithmetic logic unit perform computation on 4-bit (or nibble) intermediate results: advantages of a shorter word are simpler circuits and higher speeds.
The instruction set consists of sixteen basic commands which perform input and output interfacing, conditional jumps and operations like addition, subtraction, increment, decrement, shift operand, magnitude comparison, Exclusive-OR, AND, NAND, OR, NOR on 4-bit data words.
И, похоже, автор интересовался конструкцией z80: "The reason we classify it a 4-bit processor is that the internal registers and the arithmetic logic unit perform computation on 4-bit (or nibble) intermediate results: advantages of a shorter word are simpler circuits and higher speeds."
В УУС автор юзает аналоги К155РЕ3: (N8223N.SN74188N).
Общий вид и размер устройства весьма симпатичны!
PS. Приподниму этот топик повыше, раз уж нас посетил сам автор проекта...
PPS. Look for english version here: viewtopic.php?t=10197
