cdj@NADC.ARPA (C. Johnson) (04/20/88)
Just a quick note... Someone (I didn't catch the name--sorry...) recently inquired about a math coprocessor for the ST. I am THINKING of adding a MC68881 math coprocessor to my ST as my senior design project for college. I was thinking of using the DMA port (and thus being able to use basically the same controller for some other pet projects such as A/D, D/A, and such). The cheapest quote I got on the MC68881RC-12 (12 MHz) was $120, and that's just the chip. The cost of the materials for the project will most likely approach $200-$300. If it works out, I was thinking of marketing it if there is a market. So tell me: If a MC68881 coprocessor with software (DMA & Motorola line-F emulator) were availible for approx. $250-$300, would anybody buy it? Getting this thing rolling will cost me a lot of bread, but if there are those (like me) who drool at the thought of a math coprocessor, then it may be worth it (besides the 'A' I'll get for my lab ;-) ). As for the interface for MWC and such, why not just modify the compiler to generate in-line 68881 code? Use line-F emulation routines to emulate the coprocessor if it is non-existant, and use a line-F DMA driver to drive the coprocessor if it IS there. Isn't that how the IBM world does it? Also, before the flames roll in, I am against using the cartridge port because: 1) Only one such device can be easily used at one time 2) It may interfere with clock/calendar boards already in use 3) Some people may actually want to use a cartridge Feedback is appreciated. E-mail is probably easiest. Christopher D. Johnson Penn State University cdj@nadc.arpa <== CURRENTLY ACTIVE ACCOUNT (until end of May) cdj@psuecl.bitnet <== Active account as of beginning of June