DAN@Mit-Ml@sri-unix (12/07/82)
From: Dan Blumenfeld <DAN@Mit-Ml> The most popular arithmetic processing chips for the S-100 bus are AMD's Am9511A and Am9512 (alias Intel 8231A and 8232 respectively). The Am9511A is an arithmetic processor capable of performing fixed and floating point arithmetic operations, as well as transcendental functions. The Am9512 is only a floating point processor, but it can manupulate both 32 and 64 bit binary floating point numbers. The Am9512 has none of the transcendental functions found on the Am9511. The two parts are packaged in 24 pin DIPs, require +5 and +12 volts, and are available in 2 MHz, 3 MHz, and 4 MHz versions. From the microprocessor's point of view, the Am9511A or AM9512 looks like a run-of-the-mill peripheral chip. A popular S-100 card which uses either the Am9511A or Am9512 is the System Support 1 Board from CompuPro (Godbout). The board has one software programmable serial I/O port, a clock/calendar chip, two vectored interrupt controllers (some of the interrupts are generated on-board), three timer/counters, two 2K x 8 EPROM (or RAM) sockets, and of course the socket for either the Am9511A or Am9512. As far as software support, a number of packages support the Am9511A or Am9512. Pascal/MT+ has Am9511A libraries which replace the software floating point and transcendental libraries, and a Am9511A package is available for use with Laboratory Microsystems' FORTH. Hope this helps out... Dan