Berkeley Hardware Prototypes (from serial computer 1951 to RISCy LISPy SPUR in 1988 and beyond)

Quite the range of prototype machines and systems here

with descriptions and photos and further links within. Notably, the progression of RISC CPUs from I to IV, relatively recently brought up to V.

California Digital Computer (CALDIC) (1951) Designed for for the benefit of Berkeley’s research, it was a low-cost machine designed for simplicity of description and operation. This serial machine used a magnetic drum memory, 1300 vacuum tubes, was a decimal computer with 10 digit words, and it operated at about 50 IPS. The magnetic drum memory was its outstanding feature, 8 inches in diameter and storing 10,000 10-digit words (about 400,000 bits). “Practically all of the design and constructions of the CALDIC is work of graduate and undergraduate students in Electrical Engineering, some 35 having been associated with the project already.” This group included Doug Englebart and Al Hoagland, pioneers of the computer and disk industries.

SPUR can be thought of as RISC-IV

SPUR chips (1988) This custom chip set enabled a multi- processor workstation. The processor is 170 mm2, contains 115,214 transistors, was fabbed in a 1.6 micron CMOS, and operates at 10 MHz. It contains a RISC processor designed to run Lisp well. The snooping cache controller is 130 mm2 in the same technology and contains 68,385 transistors. The floating point unit is 130 mm2 in the same technology and contained about 110,000 transistors.

Cache controller chip: