rlf@mtgzy.att.com (r.l.fletcher) (01/05/89)
I havent really been scrutinizing the hardware details of this upgrade discussion but I have a question: Is it possible to build this board so that it contains PROVISIONS for both upgrades and allows the installer to select just the one they need via a jumper setting or presence of an IC? This way the board could be built with the idea of a combined upgrade in mind and if you dont need the P5.1 upgrade you dont enable it. Two versions could be distributed, one for a combined upgrade and a cheaper one without the necessary parts for the P5.1. It may add to the cost/complexity a bit but it seems to me if you are adding 2 MAXTORs to your box, $5 more you aren't going to miss. Is it possible? Me, I want both in one shot. Ron Fletcher AT&T Bell Laboratories Middletown NJ att!mtuxo!mtgzy!rlf
david@ms.uky.edu (David Herron -- One of the vertebrae) (01/07/89)
I have neither upgrade in my machine as of this moment
I would like to have both
I see the logic involved in keeping the upgrades seperate
I will install both upgrades as soon as they are available, at the same time
The people who are screaming for more disk space, do you also have your
expansion slots all full? I only have one expansion slot full .. (a
COMBO board). It would be "good enough" if the upgrade board were to
sit in one of those slots, wouldn't it? er.. oh.. but the components
are on the other side of the mother board and that might cause a problem?
oh well
That's my opinion (with visions of two Quantum 80's on a Unix PC dancing
through my head :-) ... Them's *FAST* drives!)
--
<-- David Herron; an MMDF guy <david@ms.uky.edu>
<-- ska: David le casse\*' {rutgers,uunet}!ukma!david, david@UKMA.BITNET
<-- Now I know how Zonker felt when he graduated ...
<-- Stop! Wait! I didn't mean to!jbm@uncle.UUCP (John B. Milton) (01/07/89)
In article <4578@mtgzy.att.com> rlf@mtgzy.att.com (r.l.fletcher) writes:
[both upgrades on one board]
I thought long and hard about it, and it would work as you describe: only
populate or enable the part you want. Putting the P5.1 PAL on my board would
mean 4 more wires from the board to the UNIXpc mother board:
1. D0
2. D4
3. /PHSTAT strobe
4. /HDSEL3 output (not really, since it goes to the 34 connector on the board)
The /RST, /MCR2SEL, Vcc, GND are already on my board.
I guess it's not that bad for people who don't ALREADY have the P5.1 installed.
As far as chopping the mother board up it would mean not desoldering 22 holes
and solding them back again. The left fan grate is close to that corner of
the board, so the wire length would not increase too much. I would not hack up
my design to try to integrate all this stuff into one PAL, rather I would have
a regular P5.1 PAL and my PAL. This would make my design 4 chips total, same
size board, same place, same connectors.
I will look at it tonight and post a follow up.
John
--
John Bly Milton IV, jbm@uncle.UUCP, n8emr!uncle!jbm@osu-cis.cis.ohio-state.edu
(614) h:294-4823, w:764-2933; Got any good 74LS503 circuits?mkp@taqwa.UUCP (Michael K. Peterson) (01/09/89)
In article <458@uncle.UUCP> jbm@uncle.UUCP (John B. Milton) writes: >In article <4578@mtgzy.att.com> rlf@mtgzy.att.com (r.l.fletcher) writes: >[both upgrades on one board] > >I thought long and hard about it, and it would work as you describe: only >populate or enable the part you want. >[etc.] Now *that's* what I want: the flexibility of having multiple drives, *and* >1024 cylinder/>8 head drives if I want them, all in doing one upgrade. I haven't done any soldering in years, so I only want to wreck my machine once... ;-) -- Mike Peterson Internet: mkp@hac2arpa.hac.com UUCP: mkp@hacgate.hac.com Home: ...!hacgate.hac.com!taqwa!mkp
jeffrey@ccnysci.UUCP (Jeffrey L Bromberger) (01/09/89)
I remember when the initial talk about the 5.1 upgrade was about, and
everyone was talking about how hard it was to find someone to burn
these custom PAL's. Are you planning to distribute these chips with
the upgrade, or is it left up to the upgrade-purchaser to find a
friend with a PAL programmer?
BTW: I favor having both upgrades on the same board. I'd like to only
pound (figuratively) on the motherboard once-it decreases the risk
of fouling something up when you play with it the second time.
--
Jeffrey L. Bromberger
System Operator---City College of New York---Science Computing Facility
Anywhere!{cmcl2,philabs,phri}!ccnysci!jeffrey jeffrey@ccnysci.BITNET