help，three unkonwn chips

[hugo929]

they write the following characters respectively.
1)Epson M80A87PB
2)Epson E05A90CA
3)NEC D7810HG
thanks for help.

[tlccomp]

[hugo929]

thank you tlccomp.
I suspect the M80A87 is a 8087. but I got blank page by google.

[unte13]

The number 2 Epson E05A90CA is a custom gate array extracted from an Epson Terminal Printer LX-300 or something like that.
2.3.1 Control Circuit Operation Overview
The printer’s system IC contains a CPU (µPD78C10A-type) that runs at 14.74 MHz, a gate array
(E05A79-type) and a main RAM ( 8KB SRAM). It oversees control of all the components in the
printer. The printer uses the E05A90 gate array to control address decoding parallel
communidion.s, PF motor drive signals, etc.

Here is a PDF:
www.danielcastelao.org/apuntes/xrosas/impresoras/SMLX300.PDF
M80A87 should request further investigation.
Can we have pictures?

[hugo929]

thank you unte13.

I am sure now m80a97 is ram then

[hugo929]

pictures coming

[unte13]

M80A87PB is a CMOS Mask ROM
http://www.ic-on-line.cn/Pdfsearch.asp?skey=LH53870
it is not RAM.