21 Jun
2009
21 Jun
'09
3:29 p.m.
Hi Tony,
Thanks Al for the heads-up on the datasheets !! Tony, do you think it is
some kind of Manchester / Miller encoder / decoder ? Do we know if it is a
National chip or has it's total identity been wiped ? Maybe Signetics or
Plessey or TI or ?? Where are the power pins ( sometimes that is a good
tell ) ? You mentioned 24 pin skinny DIP ? I'll keep looking. This is for
some type of magnetic disk / floppy media system ?
Pinouts are the same for the AMD 8051 / 8053. Hope that helps.
Best regards, Steven
versions
>
> Tony,
>
> I have a datasheet for the DP8464 ( supposed to be similar to the 8468 )
and
That datasheet is on Datasheetarchive, so I'd got a pinout of that. The
8468 is similar in consept, but has more pins (I think it only came in a
PLCC package) and thus a diferent pinout
> a bunch of Application Notes for using that family of parts ( i.e.
AN774,
> AN414, etc..). It would be helpful to know if it
is a pulse detector,
data
separator or
whatever function you think it might serve.
Thanks to Al Kossow, I've now seen all the datasheets (on bitsavers) and
know that, alas, none of them apply to the chip I am looking at. The
power and groudn pins don't agree, for example.
All I can tell you is that it's some kind of data encoder/decoder. The
Read and Write data signals, together with the Read and Write clock lines
go directly to it. I've not traced out enough to know more.
>
> I also have a datasheet for the AMD8751 / 8753 which are the EPROM > of the factory mask ROM 8051 and 8053. The 8753
has 8 K of EPROM and
same
functionality
as the 8051 / 8751 ( 4 K ROM / EPROM ).
If you've got the data sheets to hamd, can you check if it's the same
pinout as the 8051, please (it looks to be).
-tony