>"allisonp@world.std.com" "Allison J Parent" wrote:
>
>> < To Allison,  The bus that drives an RA-81, how fast can you push this?
>>
>> I know they are fast but I don't know the details.  I think in excess of
>> 14m bytes/sec, could be higher.  Also depends if they are CI connected or
>> Massbus and all that.
>
>The SDI bus be clocked at up to 22Mbits/sec or so with a max cable length of
>maybe 80 feet (plus some allowance in the start and end cabs). The RA81
>(introduced in 1982?) has a peak transfer rate of 17.4Mbits/sec and a capacity
>of 456MB. By way of contrast the RA92 (1.5GB) runs at a peak transfer rate of
>22.16Mbits/sec.

Then why were they so damn slow even when connected to a "fast" VAX on a 
fast HSC or even a high end SDI controller?    So slow we were wishing we
had our Massbuss disks back.    :-(

>Antonio

Jim