[comp.sys.att] Which is easiest?

lenny@icus.islp.ny.us (Lenny Tropiano) (07/26/89)

In article <9056@chinet.chi.il.us> ignatz@chinet.chi.il.us (Dave Ihnat) writes:
...
|>1)  The ICUS mod will require removal of the PAL, and modification and/or
|>    addition to the jumper wires installed on the motherboard for the P5.1
|>    upgrade.  Some of these wires, however, are usable as-is.
|>
True.

|>2)  The Milton mod will only require removal of the PAL, and insertion of
|>    a daughter board.
|>
Sorta ... his requires removal of wires too (just like ICUS') as well as
the addition of wires for the *DDRIVE1 (and his other drive select lines).

|>(Of course, this disregards changes in the control and data cables between
|>the extant drive and controller, which should be the same for both.)
|>
Yes and no ... ICUS plans only allow for two drives (what is currently only
allowed in the operating system -- and at this point doesn't look like it's
going change, although I'm still working hard to change this fact) ...
Milton's upgrade allows for 4 drives (two usuable with the current OPSYS,
and hopefully in the future the other two) so the cables are slightly more
complicated with his.  He requires 4 edge connectors on the 34-pin cable 
(for a total of 4 drives), as well as 4 20-pin ribbon-cables.  Since ICUS'
only provides for one extra disk, you only need two 34-pin edge connectors
and cable, as well as one additional 20 pin cable with appropriate connectors.
(Assuming you use the one in the machine for the first drive, this can
be the same for Milton's as well)...

I'm sure if you want to only make the cables for two drives, then there
is absolutely no difference.  Of course if John plans on distributing the
appropriate cables (premade) with his premade board then that's a 
different story ... So what do you say John?

|>In this case, then, is it safe to assume that the Milton modification is the
|>simplest for those who've already done the P5.1 upgrade?
|>
I'm sure we can debate the issue as far as it goes for motherboard wiring
work ... Both require enough knowledge and expertise to solder on the 
motherboard!  Keep any of your maniac friends away with his/her mega-watt
soldering gun!   Granted if you don't want to build the small board
with the few TTL chips and driver/receiver chips, then John's board is
definately the way to go.   What is the expected date for the world, John?
Last I heard you are just about to go beta with it ...  How long do you
expect to beta-test it?

|>Thanks, in any case, to all of you who've put so much work into this project.
|>
You're welcome!   Thanks to everyone for all the support we've gotten!

-Lenny
-- 
Lenny Tropiano             ICUS Software Systems         [w] +1 (516) 589-7930
lenny@icus.islp.ny.us      Telex; 154232428 ICUS         [h] +1 (516) 968-8576
{ames,talcott,decuac,hombre,pacbell,sbcs}!icus!lenny     attmail!icus!lenny
        ICUS Software Systems -- PO Box 1; Islip Terrace, NY  11752

jbm@uncle.UUCP (John B. Milton) (07/27/89)

In article <928@icus.islp.ny.us> lenny@icus.islp.ny.us (Lenny Tropiano) writes:
>In article <9056@chinet.chi.il.us> ignatz@chinet.chi.il.us (Dave Ihnat) writes:
>...
>I'm sure if you want to only make the cables for two drives, then there
>is absolutely no difference.  Of course if John plans on distributing the
>appropriate cables (premade) with his premade board then that's a 
>different story ... So what do you say John?

There is likely to be so much variability in the lengths and positioning of the
connectors that I don't think it would be practical.

...
>with the few TTL chips and driver/receiver chips, then John's board is
>definately the way to go.   What is the expected date for the world, John?
>Last I heard you are just about to go beta with it ...  How long do you
>expect to beta-test it?

Right now it is taking four (4) hours of continuous time to build each board!
That does not include debugging. More practice and some better tools will help
a lot. Because of the connectors on both sides and lack of a solder mask it
would be difficult to apply mass production technology to speed things up.
Most of the time comes from the number of solder joints (318), and the fact
that it's packed into such a small space (2.4 x 3 inches). I do not expect
beta testing to last very long. I have had the board doing several all night
formats and intra-drive massive cpio -p type stuff.

John
-- 
John Bly Milton IV, jbm@uncle.UUCP, n8emr!uncle!jbm@osu-cis.cis.ohio-state.edu
(614) h:294-4823, w:785-1110; N8KSN, AMPR: 44.70.0.52; Don't FLAME, inform!