Subject: Re: RTC on AlphaStation 600
To: Matt Thomas <matt@3am-software.com>
From: Sean Davis <dive@endersgame.net>
List: port-alpha
Date: 09/03/2003 19:00:54
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On Wed, Sep 03, 2003 at 06:20:57AM -0400, Sean Davis wrote:
> On Wed, Sep 03, 2003 at 02:28:02AM -0700, Matt Thomas wrote:
> >=20
> > On Wednesday, September 3, 2003, at 02:20 AM, Sean Davis wrote:
> >=20
> > >Okay, this is a two-part question:
> > >I have an AlphaStation 600 5/266, which has a DS1287 RTC (mcclock(4))=
=20
> > >on the
> > >motherboard. Maxim/Dallas Semiconductor is sending me a DS12887 (which=
=20
> > >is
> > >their replacement for the 'outdated' DS1287, supposedly=20
> > >pin-compatible) for
> > >free. My questions are:
> > >
> > >1) will mcclock(4) know WTF is going on if I replace the DS1287 RTC=20
> > >with a
> > >   DS12887 RTC (the hardware info implies as much, but docs and=20
> > >experience
> > >   are different ;)
> >=20
> > Actually, the real question is will the SRM be happy with it.  If it's
> > software compatible, it'll probably wonder where all the settings went.
> > So be prepared to reenter boot_device, etc.
>=20
> Yes, that is true. However I'm ready to reenter settings if necessary. I'm
> just wondering if it's possible. The docs I can find on the DS12887 imply
> that most things made for the DS1287 should work with the DS12887. There =
is
> no list of specific things using the DS1287, but it's safe to assume an
> AlphaStation 600 uses one, given the first few lines of the mcclock manpa=
ge
> and the fact that mcclock is detected and attached on this machine.
>=20
> Also, aren't the SRM settings stored on the same flash as the SRM/AlphaBI=
OS
> stuff itself? ISTR reading that there was something like 1k allocated for
> settings in the flash... of course I can't find that pdf now...
>=20
> >=20
> > >2) Is it worth the effort of removing the motherboard, desoldering the
> > >   DS1287, and soldering in the DS12887 to try it? has anyone done this
> > >   before?
> >=20
> > Is the DS1287 actually soldered?  Usually Digital used sockets for clock
> > chips.
>=20
> I'm not sure; I have not examined the motherboard that closely. If it is =
in
> a socket, not soldered in, that makes replacing it with the old one if it
> doesn't work a whole lot easier.

I just checked, it is soldered in, flush with the motherboard. Replacing it
isn't gonna be as easy as I'd hoped.

-Sean

--=20
/~\ The ASCII
\ / Ribbon Campaign                   Sean Davis
 X  Against HTML                       aka dive
/ \ Email!

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