Thanks for the information on the single chip mode with ports A and BI didnt know about that!
Although, I am trying to access both the 32K SRAM chip and 32K (of the 128K
EEPROM) chip in multiplexed expanded mode. I already have the 573 latch in
place for [A0:A7] and everything is wired up. I used the "MD 8000 FFFF"
command in BUFFALO to check if I can access the EEPROM, and the last set of
code that I had burned on there with a EEPROM programmer is still there,
which hopefully means the chip is still in good condition. However, I would
like to know how to do on-board external EEPROM burning with this setup. I
don't intend on using this unit as a full time programmer, I just want to be
able to update the code on the EEPROM without an expensive chip programmer
or other external hardware. And of course, I would like to be able to run my code from the external EEPROM as well. I know a large number of people use
this sort of setup, with some sort of third party software to burn their
EEPROMs without a trip to the programmer, it has something to do with
bootstrap mode and the INTERNAL EEPROM. If you guys have any information
on the sort of software I should be using, or the jumper settings on my
board, or any tips or tricks would be greatly appreciated.

THANKS AGAIN!

I once put a 32K NVRAM on ports A and B on a 711E9 based EVBU. It was
for archiving data so I just accessed it through the ports while in
single chip mode. BUFFALO let me drive it with my internal EEPROM/EPROM
residing program. Note: although I basically wired it up like the pink
book showed (including latch) for expanded multiplexed mode, I was
driving it in single chip mode.

Let me know if you have any questions.

Emmett Redd Ph.D. mailto:E...@missouristate.edu
Associate Professor (417)836-5221
Department of Physics, Astronomy, and Materials Science
Missouri State University Fax (417)836-6226
901 SOUTH NATIONAL Dept (417)836-5131
SPRINGFIELD, MO 65897 USA

"When I was a child, I spake as a child, I understood as a child, I
thought as a child: but when I became a man, I put away childish
things," like being too embarrassed to ask questions which my peers
might think as stupid.

________________________________

From: m... [mailto:m...]
On Behalf Of c...@yahoo.com
Sent: Wednesday, August 09, 2006 8:13 PM
To: m...
Subject: [m68HC11] External RAM and EEPROM

Hello everyone, I have a question regarding the M68HC11EBVU. Its
the old
board from the 90's with the mc68hc11e1 chip in place of the e9.
I've
installed a 32k SRAM chip and a 128k EEPROM chip on the wirewrap
side and
I've been wondering on how to interface it correctly so that I
can program the external EEPROM via the MCU. I've never used any other
software such as
pcbug11 etc. How can I do this? Can the buffalo monitor or some
other
software accomplish this? If anyone could help out Id appreciate
it very
much. THANKS!!!

Hello everyone, I have a question regarding the M68HC11EBVU. Its the old
board from the 90's with the mc68hc11e1 chip in place of the e9. I've
installed a 32k SRAM chip and a 128k EEPROM chip on the wirewrap side and
I've been wondering on how to interface it correctly so that I can program the external EEPROM via the MCU. I've never used any other software such as
pcbug11 etc. How can I do this? Can the buffalo monitor or some other
software accomplish this? If anyone could help out Id appreciate it very
much. THANKS!!!