68882 LCPDS

#1 Fri, 12 Mar 2010 - 03:32

In a box of parts, I have a 16MHz 68882 in a socket on what I think is a right angle LCPDS card. It is a small device, shaped rather like an LCPDS network card, but that could just about fit inside a normal cigarette box instead.

Can anyone tell me what machine or machines this card could be for?

#2 Fri, 12 Mar 2010 - 04:25

Do you have any pictures?

#3 Fri, 12 Mar 2010 - 09:47

well that would be for any LC that has a 68020 or 68030 CPU that doesnt have a CPU on board... should be LC and LC II - LC III(+) had a socket for a FPU onboard, right? oh and they would be too fast i guess.

#4 Fri, 12 Mar 2010 - 12:33

I thought the 68882 was matched with a 68030, but it can work with a 68020 too?

#5 Fri, 12 Mar 2010 - 17:37

Sounds like an FPU card. I have one for my LC.

#6 Sat, 13 Mar 2010 - 02:55

The 68020 was usually mated to the 68881. I'm not sure if they can be interchanged or not. The card is probably for the LC II and III/III+ (or maybe just the III/III+ if the connector has the extra pins).

I do have a 68882 card for my Classic II, and it is indeed tiny. (The FastMath Classic II card, as it is known, plugs into that rarely-used expansion slot on the logic board of the Classic II).

#7 Sat, 13 Mar 2010 - 11:12

LC III(+) wont work as theyre 25/33mhz, arent they? the 68882 on his card is 16mhz tho...

68882 would work with 020s... Im running a 68882 in my LC myself.

#8 Mon, 15 Mar 2010 - 14:52

A 68882 will work in place of a 68881. They are pin compatible. The 68882 is a more efficient update to the 68881 that is capable of scaling to higher clock speeds. The instruction set is the same as in the 68881. This is why a 68882 is preferable to a 68881 if you can find one. Your floating point results will always be better with a 68882 at the same clock speed. If you can upgrade your machine to a full 68040, though, that would be the best upgrade of all because apart from the obvious advantages the 040 has over the 020 and 030, from a purely floating point standpoint the FPU in the 68040 is far faster than even the fastest 68882 and can be accessed more quickly because it is on die.