DIP switches, NVRAM problem and some questions

[Giuseppe Gallone <gallone%ing.unipi.it@localhost>]

Hello,
I have a Sony NWS3260 and also I have a very poor original manual
reporting some technical specifications, the I/O ports pin assignments
(all ports but the expansion one) and the ROM monitor language.
So, in the following I report some information about DIP switches.
I also give a report of my experience with NVRAM.

First, the DIP switches.
My machine has two of these multiple switches, which are easily accessed
by removing the cover of the RAM SIMMs room.
They are named SW2 (8 switches) and SW3 (4 switches).
Description of SW2 as from the manual:
--------------------------------------
Default DIP settings for SW2:
   SW2
  1   OFF
  2   ON
  3   OFF
  4   OFF
  5   ON
  6   OFF
  7   OFF
  8   OFF

You can change the settings according to this table:

Switch 1-3 (Console Setting Bits):
   1,2,3 = OFF: The console is an ANSI standard terminal
                (9600bps, 8 bits, no parity, 1stop bit).

   1,3 = OFF and 2 = ON (default): Use built-in LCD
   *Make sure to set as stated above

Switch 5 (Starting Program at Power-on Bit):
   ON = Autoboot
   OFF = ROM Monitor

Switch 4,6-8: sets OFF
-------------------------------------

Description of SW3 as from the manual:
-------------------------------------
"The DIP switches are already set as:

   SW3
  1   OFF
  2   OFF
  3   OFF
  4   ON

Do not change the settings."
-------------------------------------

I've played with the SW2 settings and I was able to boot the system from
an IOMEGA SCSI ZIP drive by starting with the ROM Monitor.


Secondly, my experience with the NVRAM.
On my model, the NVRAM is a thick chip which is located on the motherboard 
just under
the floppy disk. Here are the inscriptions on the NVRAM chip:

   STI 99048
   MK48TO2B-25

If accurately examined, it appears to consist of two layers:
the lower part contains the silicon circuit, while the upper one is a 
"plastic bath"
for an hidden and common 3V battery cell. It is this cell that, when 
becomes exhausted,
causes boot problems.
This NVRAM chip can be easily found at electronic components stores for 
about $10:
in effect, although I live in a small town I was able to purchase this chip 
at the
second store I tried.
It looks to be a little hard to replace the chip, as it is directly 
soldered to the board.
Eventually, I went after this problem by (literally) breaking into the 
"plastic bath":
so I dug out the cell and then I connected the two terminals for the power 
supply of
the chip to an external 3V battery cell. These terminals are located at the 
edge, in the middle of the short side of the chip (one of those two not 
originating the pins).
The result: It still works very well and when it'll happen again... I'll 
have a much
easier life!
Suggestions for this procedure:
1) be extremely careful when digging into the chip, as you can damage the 
whole board;
2) don't forget to get (or to ensure you can get) a new chip BEFORE 
starting the attack.
3) I know of other people who did it!

Lastly, two questions:
1) is there anybody who knows how to boot these machines from a network?
2) is there anybody who knows something about the expansion port?
Please, let me know about these points.

Thanks,

Giuseppe

-------
Giuseppe Gallone
1) Dipartimento Ingegneria Chimica, Chimica Industriale e Scienza dei 
Materiali,
Universita` degli Studi di Pisa -  via Diotisalvi, 2  -  I56126 PISA - Italy
tel.  +39 050511207 - fax  +39 050511266
2) INFM, Unita` di Ricerca di Pisa, via F. Buonarroti 2 - I56127 PISA - Italy
tel. +39 050844511 - fax: +39 050844333