From: bgrubb@dante.nmsu.edu (GRUBB)
Subject: Re: Why VESA Local-Bus ????
Organization: New Mexico State University, Las Cruces, NM
Lines: 20
Distribution: world
NNTP-Posting-Host: dante.nmsu.edu

guyd@austin.ibm.com (Guy Dawson) writes:
>How about an VLB ethernet card? Move the data into the card at
>130 odd MB/s and then wait for it to tickle onto the net at
>just over 1Mb/s.
How about 250MB/s for 64-bit VLB or 350MB/s for QuickRing {Apple's
implimentation of VLB (Byte 10/92:132)} QuickRing is interesting in that
it allows interleaving with other card so that the 350MB/s can be divided 
among many cards at the same time {NuBus 90 and MCA are about the only card 
interfaces able to DO anything with that kind of speed and even NuBus 90
ditzes around at ~30MB/s with a burst mode: 80MB/s.
"MCA {Also called Micro Channel}
 IBM's 16 and 32-bit bus; "allows use of more than one CPU in a computer" 
 (DCT) and anything can talk to anything, >>as fast as the two components 
 involved can handle it.<< Never took off because it was incompatible with ISA 
 and EISA.  Planned to be bus interface of IBM PowerPC 601 (Carl Jabido).

IDA can't handle VLB speed never mind QuickRings's speed so it is out.
EISA pokes along at NuBus Mac II speeds {~15MB/s burst mode: 33MB/s}
 so VLB and QuickRing are slowed down by it.
PCI is a competing interface that is still in development.
