jbm@uncle.UUCP (John B. Milton) (12/13/88)
Hey folks,
Yes, I am still out here. YES, the second hard drive is STILL GOING TO HAPPEN!
I have had questions from people who couldn't quite figure out how to do the
hardare patch to the 512k memory boards, so this is as upgrade to HwNote06.
I will call this HwNote06.01. Keep the old 06 around, just append this to it.
Once again, this concerns using the 512k (0.5M) RAM ONLY BOARD with a FULLY
populated EIA/Combo board. If you don't have both of these ingredients, you
can't make this batch of cookies. According to the manuals, there is no way to
have both a fully populated (i.e. 1.5M) Combo Card in your system AND a 512k
memory board, which would give you a complete 2M of expansion RAM. Well, as I
pointed out in HwNote06, this is not quite true, if you're willing to get out
the solding iron...
If you want the long version, with all the details, see HwNote06.
*** PROCEDURE TO FORCE A 512K MEMORY ONLY CARD TO WORK WITH A 1.5M COMBO ***
1. Read all this through first! Print it out, as it's tough to read when the
system is powered down.
2. Contemplate whether you think you can really do this. If you think you
might be able to, but you're not sure, get a hardware person to be around
while YOU do it.
3. Get a working 512k board, a low wattage soldering iron, rosin core solder,
a sponge to wipe the soldering iron tip on, some wire wrap wire or other
fine wire, a copy of the diagnostic disk, some anti-static stuff, one of
those wrist ground straps (if you're into anti-static bondage), and a
"solder sucker". No, this last item does not have to do with the one before
it, rather it is a device for quickly removing molten solder from a hot
solder joint. I prefer one of these, rather than solder wick. If you have
not used a solder sucker before, get a scrap PC board to practice on. Any
board from an IBM-PC will do :).
4. Shutdown your machine from the silly menus or with the "shutdown" command.
You have to be logged in as root to do this.
5. Re-boot the system with the diagnostic disk and park the hard disk heads if
you have to. Some hard disks need it, some do it themselves, thank you.
6. Turn the POWER OFF, and wait for the hard disk to completely stop spinning
before you slam the machine around.
7. Take the Combo card out. There should be two little phillips head screws
holding it in. Set it aside on some anti-static stuff.
8. Get out the 512k card and put it in any slot.
9. Wonder why you didn't use the static bag the 512k card was in from step 5.
10. Turn on the soldering iron, get the sponge wet, put it out of the way.
11. Boot diagnostics. It should say that you have 524227 bytes Expansion memory.
It's lying! You really have 524228 bytes.
12. Type "s4test" at the prompt.
13. Type "15" at the expert> prompt to test memory.
14. It will test the main board memory first, and then the expansion. Notice
what the address of the EXPANSION memory is. It should be ${20,28,30}0000
for slot {0,1,2}.
15. Don't walk away while it's testing memory, hot soldering iron.
16. Park the heads, power down and take the 512k card out.
17. Examine the area around the connector. See figure 1 below.
18. Solder suck pins 30 and 29 on the connector. Break them loose and pull them
all the way out of the holes. This can be tricky since the pin is the
spring stuff the connector contacts are made out of. It takes a
surprisingly large amount of force to get them out.
19. Insulate these two connector pins with tape. If they bend back down to the
solder pads after you're done, IT WILL SHORT +5 TO GND AND MAY BURN OUT
YOUR POWER SUPPLY!
20. With a piece of wire, connect the two board HOLES where the pins WERE to +5
You could use any +5 on the board. I used the leg of resistor R6 closest to
resistor R2. (see figure 2 below)
21. All done with the dangerous stuff. Unplug the soldering iron.
22. Put some kind of sticker on the board down at the other end of the board,
so some other fool will know why this board behaves so weird. Something
like "HARD ADDRESSED TO MEMORY SLOT 3, address $380000"
23. Put the board back in, CAREFULLY power up. Lean over and listen as you
click the power on. If the phone relays go click click click click click
real fast, OR NO RELAYS CLICK, you've got those pins I told you to be
careful with shorted! TURN THE POWER OFF IMMEDIATELY. Check pins 29 and 30
and make VERY sure they're no touching anything. If your hard disk does
not spin up, you may have ONE OF THOSE drives where the brake melts to the
spindle. Take all the cards out and try to power it up again. If the hard
drive still won't spin up, ****LIGHTLY**** spin the spindle shaft to
break it loose.
24. Do 9 to 12 above. You should see that the address of the expansion memory
has changed from what it was to $380000. It won't matter what slot you put
the modified 512k card in anymore.
25. Park, power down, add the Combo Board, do 9 to 12 above. It will take
quite a while to check out all the memory, especially if this brings you up
to 4M. When you boot the diags, you should see a total of 2M expansion RAM.
26. Put the cover plate on over the 512k RAM card.
27. Re-boot UNIX and make sure the memory amounts UNIX reports are right.
28. Did you really turn the soldering off?
29. Pat yourself on the back. (if you need it)
30. Watch your system over the next few hours to make sure it's not overheating.
Summary:
Shut down, power down, lift and insulate pins 29 & 30, connect where they used
to be to +5, label it, put it in any slot, test with diags, re-boot.
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| * ^ ^ |
| `-- 33 `- 1 |
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Figure 1.
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R2
Either of these --> --===--
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# R6
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Figure 2, enlargement of the * in figure 1.
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A repeat of SOME of my advice from HwNote06:
Now for some advice. The power supply in this machine is wimpy. Adding one more
card to your machine may push it over the edge. After all this, you may have to
take the 512k card out and forget about it. I can't seem to find any guide as
to which boards draw how much power, so you'll just have to guess it out. If
your hard drive won't spin up with the 512k board in, that's a good sign you're
near the limit.
I have heard conflicting information from many different sources about the 3b1
power supplies. Some people swear up and down that the 3b1 power supply is
exactly the same as the 7300 power supply except for the drive cable. Other
people say that the 3b1 power supply is definately a different, heftier critter.
Would someone who has access to both please tell the rest of us the real story?
If you have a 1.5M Combo board, you're already in the 2M to 3.5M range. Adding
another 512k isn't going to make a whole lot of difference unless you have a
lot of users or you're running some program (KCL?) that's a big memory hog.
As always, e-mail me if you have any trouble or my instructions differ from
what you see.
Stay tuned.
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?len@netsys.COM (Len Rose) (12/14/88)
This news group is for 3B2,3B5,3B15,and 3B 4000 machines.. Please keep your 3B1/Unix PC postings on the appropriate newsgroups.
gws@n8emr.UUCP (Gary Sanders ) (12/15/88)
In article <11041@netsys.COM> len@netsys.COM (Len Rose) writes: >This news group is for 3B2,3B5,3B15,and 3B 4000 machines.. >Please keep your 3B1/Unix PC postings on the appropriate >newsgroups. WHat is your problem Len.... You posted to 3 groups unix-pc.general, comp.sys.att and u3b.tech. unix-pc.general is for unix-pc/7300/3b1 items comp.sys.att is for all at&T items u3b.* is for all 3Bx If I remember right, when the group was formed it was to include the 3B1...oh well.... But if you want to be that way keep your complaints out of unix-pc.general. -- Gary W. Sanders (osu-cis!n8emr!gws, gws@osu-cis) (cis) 72277,1325 (packet) N8EMR @ W8CQK (ip addr) 44.70.0.1 HAM/SWL/SCANNER BBS (1200/2400/19.2-PEP) 614-457-4227
reza0@ihlpl.ATT.COM (H. Reza Zarafshar) (12/15/88)
In article <11041@netsys.COM>, len@netsys.COM (Len Rose) writes: > This news group is for 3B2,3B5,3B15,and 3B 4000 machines.. > Please keep your 3B1/Unix PC postings on the appropriate > newsgroups. Wrong!!!!!!!!!!!!!!! This newsgroup as the name very clearly states is for all AT&T computers and 3b1 as you are well aware is an AT&T product that is discontinued but nevertheless it is an AT&T computer and people have every right to be talking about it here. I strongly recommend that you type "n" after the subject matter does not conform to your desires!!!
paddock@mybest6.UUCP (pri=-20 Steve Paddock) (12/20/88)
In article <8178@ihlpl.ATT.COM= reza0@ihlpl.ATT.COM (H. Reza Zarafshar) writes: =In article <11041@netsys.COM>, len@netsys.COM (Len Rose) writes: => This news group is for 3B2,3B5,3B15,and 3B 4000 machines.. => Please keep your 3B1/Unix PC postings on the appropriate => newsgroups. = =Wrong!!!!!!!!!!!!!!! =This newsgroup as the name very clearly states is for all AT&T computers =and 3b1 as you are well aware is an AT&T product that is discontinued but =nevertheless it is an AT&T computer and people have every right to =be talking about it here. I strongly recommend that you type "n" after =the subject matter does not conform to your desires!!! I disagree. I usually try to help in this matter with e-mail, but will post for the record. The u3b groups were formed, as I recall, out of the 3b2 mailing list. The distribution is non-backbone so no vote was taken. The primary purpose of both the 3b2 mailing list and this series of groups was to avoid the use of the n key on unix-pc and 6300 items. I wouldn't post 3b2/5/15/4000 items to the unix-pc distribution unless the item had true broad applicability, given the vast differences between the 7300/3b1 and the 3b2/5/15/4000 machines. I ask you to observe the same guideline. Thanks, Steve -- ------------------------------------------------------------------------------ Steve Paddock uunet!bigtex!mybest!paddock; paddock@mybest.cactus.org ut-emx!mybest!paddock {attmail|gbsic5|bscaus}!uhous1!paddock