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"Bit slicing is a technique for constructing a processor from modules of processors of smaller bit width, for the purpose of increasing the word length."

Okay bit processors were CPU construction sets. :-)

In the late 70's, bit-slice processor sets were used for high-speed activities like floppy-drive and hard-drive controllers, maybe graphic boards, maybe fast-math boards. Microprocessors of the time were too slow. Chip-sets like Western Digital's for floppy or harddrive control (ie custom microcontrollers) weren't invented yet. Only mainframes and minis were a market for discrete-logic controllers. So bit slices filled a need at the time. Look for old bit-slice stuff among those controllers, on S-100 and Multibus boards, and on mini's like PDP-8's, 11's, Novas, etc. You'll also see non-CMOS high-speed processors, like Signetics 8X300. A kind of predecessor was ALU chips like the 74XX181 chips, with related carry and shift and register chips in the series. Again - minicomputer CPUs were often constructed from such chips. Some CPUs were made from bit slices too. They were all the bleeding edge at some point. David Gesswein mentioned the Tektronix graphic terminals as an example. Regards, Herb Johnson -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net preserve, recover, restore 1970's computing email: hjohnson AT retrotechnology DOT com or try later herbjohnson AT comcast DOT net