15 Jul
2005
15 Jul
'05
9:18 p.m.
All:
I decided to run a memory test on some boards I have and I found a
bad chip. It's on a CompuPro RAM14 and the chip is a MM2147J. None of my
other 16k boards has this chip (VG boards; contain 2114s but the boards have
"BAD" labels on them so I've never plugged them in). The chip does not have
a speed marking that I can see and I don't have a copy of the RAM14 manual
although it might be similar to the Godbout EconoRam IV which uses the
40144/mm5257 chips.
Can anyone help me with a suitable cross for this chip...and a
source? My usual haunts don't show stock on this number.
Thanks.
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: http://highgate.comm.sfu.ca/~rcini/classiccmp/
/************************************************************/
16 Jul
16 Jul
6:40 a.m.
I'm pretty sure I have some 2147's around here.
Are you in a rush for these?
----- Original Message -----
From: "Richard A. Cini" <rcini at optonline.net>
To: "CCTalk" <cctalk at classiccmp.org>
Sent: Saturday, July 16, 2005 12:18 AM
Subject: S100 RAM replacements
All:
I decided to run a memory test on some boards I have and I found a
bad chip. It's on a CompuPro RAM14 and the chip is a MM2147J. None of my
other 16k boards has this chip (VG boards; contain 2114s but the boards
have
"BAD" labels on them so I've never plugged them in). The chip does not
have
a speed marking that I can see and I don't have a copy of the RAM14 manual
although it might be similar to the Godbout EconoRam IV which uses the
40144/mm5257 chips.
Can anyone help me with a suitable cross for this chip...and a
source? My usual haunts don't show stock on this number.
Thanks.
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: http://highgate.comm.sfu.ca/~rcini/classiccmp/
/************************************************************/
6:41 a.m.
Rich,
Do you have a date for these? I don't have all my data books here but I
checked in my 1980 and 1981 D.A.T.A. books and they don't list the MM2147
but they do list a TI version (TMS21L47). Those are 4k x 1 RAMs 5 volt only
RAMs. Your parts are probably the same. BTW MM is Monolithic Memories. I
think I have some 2147s in my spares. How many are you looking for?
I don't have any listing for 5257s in these books so I can't tell you
anything about them.
Joe
At 12:18 AM 7/16/05 -0400, you wrote:
All:
I decided to run a memory test on some boards I have and I found a
bad chip. It's on a CompuPro RAM14 and the chip is a MM2147J. None of my
other 16k boards has this chip (VG boards; contain 2114s but the boards have
"BAD" labels on them so I've never plugged them in). The chip does not have
a speed marking that I can see and I don't have a copy of the RAM14 manual
although it might be similar to the Godbout EconoRam IV which uses the
40144/mm5257 chips.
Can anyone help me with a suitable cross for this chip...and a
source? My usual haunts don't show stock on this number.
Thanks.
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: http://highgate.comm.sfu.ca/~rcini/classiccmp/
/************************************************************/
7:18 a.m.
All:
Through Randy, I actually found these at JDR Microdevices, so I
ordered a few, which I should have this week. Thanks a lot.
Rich
-----Original Message-----
From: cctalk-bounces at classiccmp.org
[mailto:cctalk-bounces at classiccmp.org] On Behalf Of Joe R.
Sent: Saturday, July 16, 2005 9:42 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: S100 RAM replacements
Rich,
Do you have a date for these? I don't have all my data books here
but I checked in my 1980 and 1981 D.A.T.A. books and they don't list the
MM2147 but they do list a TI version (TMS21L47). Those are 4k x 1 RAMs 5
volt only RAMs. Your parts are probably the same. BTW MM is Monolithic
Memories. I think I have some 2147s in my spares. How many are you
looking for?
I don't have any listing for 5257s in these books so I can't tell you
anything about them.
Joe
At 12:18 AM 7/16/05 -0400, you wrote:
All:
I decided to run a memory test on some boards I have and I found
a bad
chip. It's on a CompuPro RAM14 and the chip is a
MM2147J. None of my
other 16k boards has this chip (VG boards; contain 2114s but the boards
have "BAD" labels on them so I've never
plugged them in). The chip does
not have a speed marking that I can see and I don't
have a copy of the
RAM14 manual although it might be similar to the Godbout EconoRam IV
which uses the 40144/mm5257 chips.
Can anyone help me with a suitable cross for this chip...and a
source?
My usual haunts don't show stock on this number.
Thanks.
Rich
Rich Cini
Collector of classic computers
Build Master for the Altair32 Emulation Project
Web site: http://highgate.comm.sfu.ca/~rcini/classiccmp/
/************************************************************/
4:39 p.m.
I decided to run a memory test on some boards I have
and I found a
bad chip. It's on a CompuPro RAM14 and the chip is a MM2147J. None of my
[...]
Can anyone help me with a suitable cross for this
chip...and a
source? My usual haunts don't show stock on this number.
I can't help with suppliers, and none of my data books give crosses for
this chip, but I can tell you that it's a 4K * 1 static RAM. The pinout
is :
1 : A0
2 : A1
3 : A2
4 : A3
5 : A4
6 : A5
7 : Dout
8 : WE/
9 : Ground
10 : CS/
11 : Din
12 : A11
13 : A10
14 : A9
15 : A8
16 : A7
17 : A6
18 : Vcc
The data sheet I have mentions a 60ns version, it sounds like a pretty
fast chip for the time. I can't believe an S100 board needs something
that fast.
-tony
7104
days inactive
7104
days old
4 comments
4 participants
participants (4)
-
ard＠p850ug1.demon.co.uk -
bshannon＠tiac.net -
rcini＠optonline.net -
rigdonj＠cfl.rr.com