[sci.electronics] Need help identifying RAM for printer buffer

edw@cbnewsc.att.com (Edwin.D.Windes@ATT.COM) (09/20/90)

I'm trying to expand the buffer in a Citizen MSP-10 printer.
I popped the cover last night, and there is an empty 28-pin
socket labeled "option buffer" (so far, so good), with a part
number "uPD61680".  The closest part I can find is a NEC 8Kx8
pseudo-static RAM, uPD6168C2.  (I suppose that I could have
misread the number on the board.)

Assuming this is the right part, could I substitute 8Kx8 static RAM?  
Else, where can I get one of these buggers?
And, assuming I fill the socket, do I have to flip some DIP switches?
Does anyone have a manual, or better yet, a schematic for this printer?

thanks.