[Techtoolslist] Can anyone identify this chip?

[Joseph Magiera]

Hmmm... I can see I attached a pic, but it didn't get through.  Sorry about that.  I have posted the pic here:
 
http://www.tollianweb.com/uc/vti.jpg
 
It's IC 1N from an Exidy 440 PCB (Whodunit in this case).  I'd really like to identify the manufacturer.  I looked at several IC logo web sites and nothing comes up.  It's in a bank of 2764's and supposedly supposed to be able to be read as a 2764, but my EETools Top Max is unable to read it.  Really a mystery to me why I can't find this symbol at all (and why if it is equivalant to a 2764 my reader can't read it).  It's not a bad chip as the game boots up and passes all self tests without any complaining.
 
If anyone might be able to identify what IC is on 6K on the same boardset type, that would be appreciated too.  On my board, it's a National 74S28(x) where "x" is either a 7 or an 8, but it's overlayed with an Exidy part number stamp.  National 74S287 crosses to an MMI 6301 (Signetics 82S129) and a 74S288 crosses to a MMI 6331 (Signetics 82S123).
 
Trying to dump a Whodunit ROM version that's not in MAME.  Thanks,
 
Joe


________________________________
From: Clay Cowgill <c.cowgill at comcast.net>
To: 'Technical Tools Mail List' <techtoolslist at flippers.com> 
Sent: Monday, November 18, 2013 11:28 PM
Subject: Re: [Techtoolslist] Can anyone identify this chip?


Hey Joe, 

The only attachment I received was some text with pointers to John's
archives.  Did you forget the attachment or did it get stripped by the time
it made it out the mailer?

-Clay

-----Original Message-----
From: techtoolslist-bounces at flippers.com
[mailto:techtoolslist-bounces at flippers.com] On Behalf Of Joe Magiera
Sent: Monday, November 18, 2013 9:24 PM
To: Techtoolslist at flippers.com
Subject: [Techtoolslist] Can anyone identify this chip?

Can anyone identify the chip in the attached picture?  I cannot find the
manufacturer's symbol or anything related to VTI.  I found one source of VTI
mentioning being acquired by Murata.  I wrote to them and they told me it
was a different VTI.  It's in a bank of 2764's, but my EETools Top Max can't
read it as a 2764.



I would really like to find the manufacturer's name.  Thanks,



Joe


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