I had a Unisys 386dx-16 MB, built by Intel that had 32-bit "ISA" slots
for memory cards. The back sections were standard ISA, so a standard
ISA card could be used, but the closest sections were for the memory
cards to used in conjuction witht e standard part. It was sort of like
VLB, but the "extra" part looked ISA, not PCI like VLB does.
The memory cards were cool looking, they were full size boards with many
rows of SIPPS soldered in.
Chad Fernandez
Michigan, USA
Tony Duell wrote:
The EISA is just about the size of the ISA, isn't it? I've never had an
interest in EISA so haven't looked at 'em in detail, but is seems to me that,
since the ISA boards plug directly into an EISA slot, they must be the same
size.
IIRC, EISA has a strange 2-level edge connector. ISA cards only go part
way into the slot, and connect to the top row of contacts (which have the
signals you'd expect on an ISA slot). EISA cards have a few notches cut
out of the edge finger area, so they go the full way in and connect to
both rows of contacts (EISA-specific signals on the lower row of contacts).
Therefore EISA has about twice as many signals as ISA. It would be
possible to put them on a conventional edge connector about twice as long
as anm ISA slot. While this wouldn't be done for the actual expansion
slots (because no standard boards would fit), I can imagine it being done
for a custom riser card.
-tony