Alexander Shabarshin of NEDOCON has created the impressive NEDONAND homebrew computer:
NEDONAND is 8-bit homebrew computer entirely built out of many 74F00 chips (2-input NAND gates)
Alexander describes the details on Hackaday.io:
I started NEDONAND in order to achieve a few goals:
- use only 74F00 chips (2-5 ns delay per gate) to get maximum possible performance (at least 1 million instructions per second)
- 8-bit data, but 4-bit ALU (similar to Z80) with carry/borrow and overflow flags (with approach similar to 6502 where borrow is inverted carry)
- no microcode in ANY form, just 2-stage pipeline and RISC instruction set (similar to PIC – 4 ticks per cycle, 1 cycle per instruction)
- open source (public domain hardware and copylefted software) and hobbyist friendly design (only through-hole components)
- all parts will be well-documented and could be used as standalone addons in other projects
- everything simulated in Logisim first (circuits are provided as a single nedonand.circ file)
- plan to build PC-connected “testbed” to test different parts of the project separately
- If you want to purchase NEDONAND boards (I share only tested ones): OSHPark/Shaos
- Hardware files for Eagle v5.12 and gEDA (pcb): Eagle files, gEDA files (it may have some untested things).
In this video, Alexander shows part of the NEONAND program counter:
Shared Projects on OSH Park by Alexander:
Hi, thanks for sharing this 🙂
Correction – video shows just a little piece of NEDONAND – part of program counter 😉
Finished NEDONAND will have hundreds of 74F00s…
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