[comp.sys.att] adding memory to 6386E

gary@ethos.UUCP (Gary J. Smith) (11/14/88)

In adding memory to the 6386E, is it necessary to purchase an add-on
board, or can memory chips be added into the empty sockets on the
original board?  I have a couple of the 1MB "Simm Kits", but the
computer fails to recognize the memory when I simply plug them into
the empty sockets.  No instructions came with the simm kits.

-- 
Gary J. Smith   
[uunet,mcnc]!ethos!gary

lee@ulysses.homer.nj.att.com (Lee Begeja[cwc]) (11/14/88)

In article <2258@ethos.UUCP>, gary@ethos.UUCP (Gary J. Smith) writes:
> 
> In adding memory to the 6386E, is it necessary to purchase an add-on
> board, or can memory chips be added into the empty sockets on the
> original board?  I have a couple of the 1MB "Simm Kits", but the
> computer fails to recognize the memory when I simply plug them into
> the empty sockets.  No instructions came with the simm kits.


My simm kitts came with an installation guide which was necessary and
sufficient to enable me to get the memory on the board.

You can add the simm chips to the empty sockets on the board but they
must be in the "correct slots" (unless you are fully populating the board).
In addition, there are 2 dip switches on the board that must be properly
set depending on how much memory you are adding.

If you cant get hold of the installationguide, email me the details
and I'll look it up for you.

Lee Begeja  201/582-5777 att!ulysses!lee

adh@anumb.UUCP (a.d.hay) (11/15/88)

In article <2258@ethos.UUCP> gary@ethos.UUCP (Gary J. Smith) writes:
-->
-->In adding memory to the 6386E, is it necessary to purchase an add-on
-->board, or can memory chips be added into the empty sockets on the
-->original board?  I have a couple of the 1MB "Simm Kits", but the
-->computer fails to recognize the memory when I simply plug them into
-->the empty sockets.  No instructions came with the simm kits.

first: you can't mix 256K and 1M simms on a board.

 _____________________________________________________________________
|			    XXXXXXXX  XXXXXXXX  		      |
|			    L07LL	L06LL   		      |
|								      |
|								      |
|								      |
|								      |
|								      |
|								      |
|								      |
|								      |
|		      ___	   _	      _ 		 _____|
|____________________|   |________| |________| |________________|

L07LL:					L06LL:
banks		2&3			256K:3&4	1M:1-4
--------------------------------------------------------------
0		1 1			     0 0	0011
0&1		1 0			     0 1	0111
0-3		0 0			     1 1	1111

			L07LL:5678	  L06LL:12,56
board	banks		256K	1M	  256K only
-------------------------------------------------------------
1	0		0000	0000		00 00
	0&1		.	.		.  .
	0-3		.	.		.  .
2	0		.	0001		01 01
	0&1		.	.		.  .
	0-3		.	.		.  .
3	0		.	0011		10 10
	0&1		.	.		.  .
	0-3		.	.		.  .

0=on, 1=off; all other switches on.

-- 
Andrew Hay		+------------------------------------------------------+
Holistic Specialist	| I will design a computer for you, so powerful that   |
AT&T-BL Ward Hill MA	| organic life will form part of its operational matrix|
mvuxq.att.com!adh	+------------------------------------------------------+

del@cpsc55.ATT.COM (Dave Lindsey) (11/16/88)

In article <2258@ethos.UUCP>, gary@ethos.UUCP (Gary J. Smith) writes:
> 
> In adding memory to the 6386E, is it necessary to purchase an add-on
> board, or can memory chips be added into the empty sockets on the
> original board?  I have a couple of the 1MB "Simm Kits", but the
> computer fails to recognize the memory when I simply plug them into
> the empty sockets.  No instructions came with the simm kits.

Yes - you can plug the 1 Meg SIMMs into open slots on a memory board.
Yes - you need to flip a few dip switches on the board AND run the UNIX/DOS
setup program to properly recognize the memory.
You can call the AT&T hotline for detailed help.

Dave Lindsay, AT&T  

mcripps@mtuxo.att.com (XMP12-M.CRIPPS) (11/23/88)

In article <357@cpsc55.ATT.COM>, del@cpsc55.ATT.COM (Dave Lindsey) writes:
> In article <2258@ethos.UUCP>, gary@ethos.UUCP (Gary J. Smith) writes:
> > 
> > In adding memory to the 6386E, is it necessary to purchase an add-on
> > board, or can memory chips be added into the empty sockets on the
> > original board?  I have a couple of the 1MB "Simm Kits", but the
> > computer fails to recognize the memory when I simply plug them into
> > the empty sockets.  No instructions came with the simm kits.
> 
> Yes - you can plug the 1 Meg SIMMs into open slots on a memory board.
> Yes - you need to flip a few dip switches on the board AND run the UNIX/DOS
> setup program to properly recognize the memory.
> You can call the AT&T hotline for detailed help.
> 
> Dave Lindsay, AT&T
  ^^^^^^^^^^^^^^^^^^
First off, "Hi Dave" from XT1145000.

Next, to save you a call to the hotline, here are the switch settings:

Capacity	Switch L07LL	Switch L06LL
1 MB		01100000	00000000
2 MB		01000000	00010000
4 MB		00000000	00110000

This is for the built in memory board and 256K SIMMs (the 1MB "Simm Kits"
come with 4 256K SIMMs).  You can only put 1, 2 or 4 MB of memory on
one of these boards (3 MB won't work).  When looking at the board with
the connectors pointing down, switch L07LL is on the left.

If you are not putting 4MB on the board, you have to place the modules
in the right slots on the board, or else it won't work.  The board is
broken up into 4 banks of 1MB each, and all slots for a bank must be
occupied before another bank can be added.  Here is a diagram of how
banks are mapped to slots on the board.

	0 --------------		------------- 3
	1 --------------  L07LL  L06LL  ------------- 2
	2 --------------		------------- 1
	3 --------------		------------- 0
	0 --------------		------------- 3
	1 --------------		------------- 2
	2 --------------		------------- 1
	3 --------------		------------- 0
			(connectors at bottom)

All of the bank 0 slots must be filled before the bank 1 slots can be
filled, etc. etc.

This is courtesy of the 6386 service manual.  Hope it helps.

Mike Cripps
AT&T Bell Laboratories
mtuxo!mcripps

david@varian.UUCP (David Brown) (11/25/88)

In article <357@cpsc55.ATT.COM>, del@cpsc55.ATT.COM (Dave Lindsey) writes:
> In article <2258@ethos.UUCP>, gary@ethos.UUCP (Gary J. Smith) writes:
> > 
> 
> Yes - you can plug the 1 Meg SIMMs into open slots on a memory board.

Just a quick warning - make sure that the RAM chips on your SIMMs are
100ns or faster.  I tried some 120ns SIMM's from a desktop 6386 in a
6386E; the memory diagnostics passed OK, but I got unexplained panics minutes
after bringing up UNIX.   This is because the 6386E (tower) runs at
20mhz, vs. 16mhz for the desktop 6386.  You can tell the speed by
looking at the part # on the chips - if it ends with something like -12,
it's 120ns, etc.  

My 6386E came with 80ns chips in the 1st 2mb (supplied by AT&T)
and 100ns chips in the 2nd 2mb (installed by the retailer). 
The Hotline tells me that we would not see any speed
improvement by using 80ns vs. 100ns - does anyone know if this is true?



-- 
David Brown	 415-649-4000
Orion Network Systems 1995 University Ave. Suite 350 Berkeley CA 94704
{pacbell,lll-crg,zehntel,ista,rtech,csi,kinetics}!varian!david

dave@westmark.UUCP (Dave Levenson) (11/27/88)

In article <697@varian.UUCP>, david@varian.UUCP (David Brown) writes:
...
> My 6386E came with 80ns chips in the 1st 2mb (supplied by AT&T)
> and 100ns chips in the 2nd 2mb (installed by the retailer). 
> The Hotline tells me that we would not see any speed
> improvement by using 80ns vs. 100ns - does anyone know if this is true?

This is true.

The speed is determined by the processor and its clock, not by the
memory chips.  The speed rating on the memory chips indicates their
fastest speed.  The CPU requires that the memory cycle in not more
than 100 nsec.  If your memory cycles faster, the CPU won't notice
the difference, and will still allow them 100 nsec.

If your memory takes longer than 100 nsec. to cycle, (e.g. if you're
using 120 nsec parts) then the CPU will be attempting to read from
memory faster than the memory will cycle, and you'll get memory
errors.

-- 
Dave Levenson
Westmark, Inc.		The Man in the Mooney
Warren, NJ USA
{rutgers | att}!westmark!dave