13 Dec
2019
13 Dec
'19
9:55 a.m.
Hi,
I?ve been trying to find *detailed* specifications (mainly detailed signal timings) for
the SMD disk interface but all I?ve found so far are the interface specifications for
individual disks (CDC, Fujitsu, etc). I?ve looked in the usual places (bitsavers mostly)
and haven?t found the spec itself. If anyone has any pointers, I?d appreciate it.
Thanks.
TTFN - Guy
13 Dec
13 Dec
10:11 a.m.
ANSI has a spec, X3.91M_1987 I don't know if it covers the SMD-E , etc.
On 12/13/19 9:55 AM, Guy Sotomayor via cctalk wrote:
Hi,
I?ve been trying to find *detailed* specifications (mainly detailed signal timings) for
the SMD disk interface but all I?ve found so far are the interface specifications for
individual disks (CDC, Fujitsu, etc). I?ve looked in the usual places (bitsavers mostly)
and haven?t found the spec itself. If anyone has any pointers, I?d appreciate it.
Thanks.
TTFN - Guy
11:35 a.m.
On Fri, Dec 13, 2019 at 11:10 AM Al Kossow via cctalk <cctalk at classiccmp.org>
wrote:
ANSI has a spec, X3.91M_1987 I don't know if it
covers the SMD-E , etc.
X3.91M-1987 section 6 covers "Interface Extensions", which includes adding
tag 4, 5, and 6, dual-port provisions, spinup sequencing, index mark and
sector mark signals, fixed-head addressing, service voltages on round
radial cable, and extended cylinder addressing. I think some of that came
in with SMD-E, but I'm not 100% certain. X3.91M-1987 describes data rates
of up to 24 Mbps, which came from SMD-E.
SMD-E is apparently defined by CDC document 64712402, which I've never been
able to obtain.
11:42 a.m.
On Fri, Dec 13, 2019 at 10:55 AM Guy Sotomayor via cctalk <
cctalk at classiccmp.org> wrote:
I?ve been trying to find *detailed* specifications
(mainly detailed signal
timings) for the SMD disk interface but all I?ve found so far are the
interface specifications for individual disks (CDC, Fujitsu, etc). I?ve
looked in the usual places (bitsavers mostly) and haven?t found the spec
itself. If anyone has any pointers, I?d appreciate it.
You've seen that the SMD spec (as of March 1981) is on Bitsavers?
pdf/cdc/discs/interface_specs/64712400_SMDCableSpec_Mar81.pdf
That doesn't cover later enhancements such as SMD-E.
14 Dec
14 Dec
8:50 a.m.
Thanks Eric, I somehow missed that one.
TTFN - Guy
On Dec 13, 2019, at 11:42 AM, Eric Smith <spacewar
at gmail.com> wrote:
On Fri, Dec 13, 2019 at 10:55 AM Guy Sotomayor via cctalk <cctalk at classiccmp.org
<mailto:cctalk at classiccmp.org>> wrote:
I?ve been trying to find *detailed* specifications (mainly detailed signal timings) for
the SMD disk interface but all I?ve found so far are the interface specifications for
individual disks (CDC, Fujitsu, etc). I?ve looked in the usual places (bitsavers mostly)
and haven?t found the spec itself. If anyone has any pointers, I?d appreciate it.
You've seen that the SMD spec (as of March 1981) is on Bitsavers?
pdf/cdc/discs/interface_specs/64712400_SMDCableSpec_Mar81.pdf
That doesn't cover later enhancements such as SMD-E.
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days inactive
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4 comments
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