http://istec.colostate.edu/activities/distinguished_lectures/tredennick_Trends2005.pdf
http://www.sasktelwebsite.net/jbayko/cpu7.html
The Rekursiv processor features a writable instruction set, and is highly parallel. The four chips were Numerik, Logik, Objekt, and Klock.
The CPU itself consisted of Numerik and Logik. Numerik was the ALU, based on AMD 2900-series bitslice CPU components (sixteen 32-bit registers, ALU, barrel shifter, 32x32-bit multiplier). The CPU was similar to the Patriot Scientific PSC1000, with sixteen registers, an evaluation stack, and a return address stack. A 64k area (16k X 128 bit words) held microcode, allowing an instruction set to be constructed on the fly, and could change for different objects. There were two program counters, one for application instructions, one for the microcode routines which implement them. Microcode used sixty-field 160-bit words.
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