wvucenic@well.UUCP (Wayne Vucenic) (03/09/86)
I'm interested in the 20Meg Atari hard disk. I had heard rumors to
the effect that the developers hard disks have a faster data transfer rate
than the soon-to-be-available commercial 20Meg Atari hard disks. I asked
about this at my local dealer, but the fellow there told me that the
only differences were cosmetic: metal case vs. plastic case. I'm not sure
he's got the straight story on data transfer rates, as he was quoting
10Mbits/sec to me. I realize that the DMA controller can transfer at that
speed, but I had heard that the hard disk controllers were actually
running at 7.5Mbits or 5Mbits.
I was wondering if anyone had the straight story on the differences
between the developers and commercial hard disks. The two topics of
particular interest to me are:
1) Performance: data transfer rates, access times, etc.
2) Fan noise. I seem to be overly sensitive to noise. (I REALLY
like the fact that my ST doesn't have a fan, but the hum
(60 cycle, it sounds like) from my monochrome monitor
begins to bug me at times. My color monitor is silent.
Anyone else have a noisy mono monitor, or is it just mine?)
Anyway, back to hard disks... the developers hard disk I
looked at had a fan that seemed to be about average for
fan noise.)
Other differences of more minor interest would include requirements for
parking the heads. I understand that the developer's hard disk requires
this, but I can't imagine that a commercial version would.
Can anyone at Atari or elsewhere shed some light on this? Thanks.
=============================================================================
Wayne Vucenic
...{ucbvax, ihnp4, allegra, decvax}!hplabs!well!wvucenic
=============================================================================nigel@minster.UUCP (03/14/86)
In article <743@well.UUCP> wvucenic@well.UUCP writes: >I'm interested in the 20Meg Atari hard disk. I had heard rumors to >the effect that the developers hard disks have a faster data transfer rate >than the soon-to-be-available commercial 20Meg Atari hard disks. I asked >about this at my local dealer, but the fellow there told me that the >only differences were cosmetic: metal case vs. plastic case. I'm not sure >he's got the straight story on data transfer rates, as he was quoting >10Mbits/sec to me. I realize that the DMA controller can transfer at that >speed, but I had heard that the hard disk controllers were actually >running at 7.5Mbits or 5Mbits. ... The developers drives have two boards in - a standard hard drive controller, and a bus convertor board. I was told around Christmas time that before selling commercially, Atari wanted to get this onto one board, and into a plastic case, so your dealer is on the right lines. 5MBits is the quoted rate for the drive, but some timings I made using an analyser (very rough) suggested the acknowledges were closer to 7MBits. If Atari wish to use a single board, then the new board may be faster. The developer setup looks like a standard SASI board, with a SASI to Atari convertor (one PAL, about 6 TTL). > Anyway, back to hard disks... the developers hard disk I > looked at had a fan that seemed to be about average for > fan noise.) Yes - average, fine by me. > >Other differences of more minor interest would include requirements for >parking the heads. I understand that the developer's hard disk requires >this, but I can't imagine that a commercial version would. There is a utility to move the heads to a safe landing point (!) for transport. The importance is not heavily stressed, just suggested. Nigel Roles