John Bell Engineering was a small firm producing microprocessor many boards between 1980 and 1990.
The early boards were 6502 and Z80 SBC’s, later boards were for the Apple II, and the last ones for the IBM PC bus.
I present here, what I have found, of John Bell 6502 boards.
Three IC’s SBS 6502 CPU, 6532 RIOT, EPROM 2532 or 2716, expansion connector, RC oscillator, one transistor decoder.
80-153 6502 micro
There was a revision, connecting phi2 to pin 11 of the ‘LS10, “to improve memory response”
(Clock modification with crystal, Don Sawyer)
There was a revision, connecting phi2 to pin 11 of the ‘LS10, “to improve memory response”, so the wire is soldered!
Pages numbered are scans from this book:
Michael Kowalski created the 6502 Simulator many years ago. It simulated the MOS 6502, CMOS 65C02, and the 6501. Daryl R...
Design by Timothy Alicie Demonstrates his design for a cassette interface for the Micro-KIM single board computer fro...
While building the Retro Chip Tester, designed by Stephan Slabihoud, and documented on his 8bit-museum website, I no...
In the Elektor Specials Elektor bus based systems were presented that could be used to build more advanced computers, ba...