The logic design of the FC-4100 data-processing system
W. A. Helbig, Arnold Schwartz, C. S. Warren, W. E. Woods, H. S. Zieper · 1961
The FC-4100 is a parallel binary computer with a thirty-bit word length. It operates at a 1.0 mc clock rate and performs approximately 50,000 operations per second. The internal memory capacity is 4,096, 8,192, or 16,384 words of random-access core storage with an access time of 1.3 microseconds. The entire data processor, with core memory, contains less than 3,000 transistors. A special feature of the computer is a program interrupt system: up to sixteen independent programs can be executed on a pre-assigned priority basis. Each program is provided with its own set of six index registers and its own program counter. Other feastures include: a special repeat mode for controlling small, iterative loops without the usual branch instructions; relative addressing; half-word multiply and divide instructions for faster operation at reduced precision; and a normalize instruction to facilitate floating-point operations.