

The Adaptec 1540-series use bus mastering.  This means that the CPU
doesn't sit waiting for data bytes, it can go off and do other
computing - if you have an advanced multi-tasking OS, that is.  DOS
just sits and waits anyway.


Why don't you start with the spec-sheet of the ISA bus first? :-) IDE
was designed to plug into ISA virtually unaided - in essence, IDE *is*
ISA, on a ribbon cable.  Therefore it's specs are the same as ISA -
8MHz clock, 16 bit width, 5MB/sec.

This is why I've concluded that IDE on VL-bus is a waste of a fast
slot.  The card's job would to slow the VL-bus transactions to ISA
speed.  Heck, that's what ISA slots do - I'll just use one of those
instead.