Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!zds-ux!zds-oem!easton
From: easton@zds-oem.UUCP (Jeff Easton)
Newsgroups: comp.sys.zenith
Subject: Re: Z-415B, COM3 (Help!)
Message-ID: <5@zds-oem.UUCP>
Date: 18 Mar 90 00:38:04 GMT
References: <2009@nosc.NOSC.MIL>
Organization: Zenith Data Systems OEM Engineering
Lines: 36

In article <2009@nosc.NOSC.MIL>, fayette@halibut.nosc.mil (Daniel F. Fayette) writes:
> Two questions:
> 
> 1.  I have inherited a Z-415B Add-on Memory Board which is now installed
> in my Z-248.  The question is, can I do anything with this other than
> making it a large RAM drive?  I do not have a Z-405 (512K to 1.1M) card.
> I only have 512K of system memory.  Can I use the Z-415B to get 640K of
> system memory?  How about expanded memory that can be managed by EMM.SYS?
> 

  All three of the Z-248 memory boards used the same bare PC board.  They
were just populated differently.  Some berg jumpers where changed, some 
wire straps where changed and some resistor packs were changed to
make the board into any of the three versions, Z405, Z415, and Z445.

  To modify the board from one version to another requires that you
hack on the board a little.  I assume you want to be able to backfill
to 640K and have 1M of extended.

  Send me email with the bare PCB number, its silk screened on the board
and is of the form 85-xxxx-xx.  Also tell me if the top row of 
memory chips are 4164's or 41256's (more than likely 41256's) and lastly
tell me if your 248 is a commercial 0 wait state version or the 
goverment 1 wait state version.

  With that info I'll try to come up with a list of jumpers and resistor
packs to move.  You will need to be proficent in desoldering parts off
of boards without destroying them, etc.


	Jeff Easton			Zenith Data Systems
	Systems Engineer		OEM Engineering
	easton@andrews.edu     --or--
	easton@zds-oem.zds.com
	 I'd rather be Water Skiing...