Profiles eight obscure 8-bit era microprocessors – TMX-1795, Mostek 5065, Intel 8085, Signetics 2650, RCA 1802, EA 9002, Intersil 6100, TMS 9900 – covering why each failed or stalled.
Key Takeaways
TI’s TMX-1795 (1971) never reached production but resurfaced as a patent lawsuit exhibit against Gilbert Hyatt decades later.
The Mostek 5065 was Motorola’s original 6800 precursor; its page-1 stack convention carried directly into the 6502.
RCA 1802 was the first CMOS microprocessor, used silicon-on-sapphire for radiation resistance, and flew on Voyager, Viking, and Galileo probes.
TI’s TMS 9900 was technically 16-bit but slower than 8-bit rivals; the TI 99/4A sold at a loss, costing TI $330M in Q3 1983 alone before cancellation.
Intersil 6100 offered PDP-8 compatibility in CMOS but its 12-bit width was too alien in an 8-bit-dominated market.
Hacker News Comment Review
Commenters note the sheer architectural divergence of the early 1970s is easy to underestimate; the x86 monoculture was not inevitable, and RISC challenges to it persisted into the late 1990s.
The observation that these hardwired designs ran on sub-million transistor counts highlights how much was achieved with minimal silicon budget.
