franky@dutesta.UUCP (Frank W. ten Wolde) (11/30/88)
I would like to know your (NetLanders) opinion about the following:
I have a AT&T 3600 (actually Olivetti M24) computer and a Seagate
harddisk (ST251-1) using a Western Digital Controller (WD1002S-WX1).
For optimum results I must set the interleave factor to 5, which
slows down the data transfer rate (disk<-->host) to appr. 100K per
second.
Other people I have spoken to, have informed me that they run with
an interleave factor of 3 (data transfer: 170K/s), on a "simple" ;-)
IBM XT at 4.77MHz.
I would think that my Olivetti (clock 8MHz) should be able to at
least the same interleave(3)/transfer rate(170K/s), but for some
reason it will not work properly.
My questions are:
1. Is there someone out there who has the same problem?
2. Is there someone with an AT&T 3600 with a data rate
of 170K/s (and a corresponding interleave of 3)?
3. Is there someone who can tell me where the problem
originates and perhaps how to solve it?
Thanks in advance,
Frank ten Wolde
franky@dutesta
--
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Frank ten Wolde (PE1FCO) | UUCP: ..!dutrun!dutesta!franky
Delft University of Technology |
Faculty of Electrical Engineering |
Section Computer Architecture |
Delft |
The Netherlands |
##########################################################################pechter@dasys1.UUCP (Bill Pechter) (12/02/88)
In article <1233@dutesta.UUCP> franky@dutesta.UUCP (Frank W. ten Wolde) writes: > > >I would like to know your (NetLanders) opinion about the following: > >I have a AT&T 3600 (actually Olivetti M24) computer and a Seagate >harddisk (ST251-1) using a Western Digital Controller (WD1002S-WX1). >For optimum results I must set the interleave factor to 5, which >slows down the data transfer rate (disk<-->host) to appr. 100K per >second. > > 1. Is there someone out there who has the same problem? We all do. The bus on the 6300 runs at 4mhz which is quite slow. If you use the on-disk controller bios rom you get a very slow transfer rate and interleave. > 2. Is there someone with an AT&T 3600 with a data rate > of 170K/s (and a corresponding interleave of 3)? I've got a transfer rate of 173k and an interleave of three. I'm running a V30 processor, the 1.43 bios rom to control disk parameters and qfresh. Before qfresh I got an interleave of 4 and 130k. My best interleave on the WD Superbios Rom was 6. Some people have had luck with a program called Ramit that loads the disk controller bios into Ram. I haven't had much luck with it. > 3. Is there someone who can tell me where the problem > originates and perhaps how to solve it? The bus board's the main problem and it's hardware. The above workarounds should help. I wish someone built an AT&T 16 bit bus disk controller!. ------------------------------------------------------------------------------- Bill Pechter {sun!hoptoad,cmcl2!phri}!dasys1!pechter USnail 103 Governors Road, Lakewood, NJ 08701 AT&T 201-370-0709 Evenings "When in doubt, swap it out." " Anyone want a PDT11/150?" -------------------------------------------------------------------------------