Newsgroups: comp.robotics
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From: seeker@indirect.com (Stan Eker)
Subject: Re: Need help adding memory to 6.270 board - or other board.
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Date: Sat, 22 Apr 1995 05:10:07 GMT
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Chris Pierik (chrisp@ix.netcom.com) wrote:
:     Hello. I am designing a robot, and I have been considering the use
: of the 6.270 board. But I think that the 32K programming space is too
: small.  Has anyone been able to increase such space?  Or are there
: similar boards with more programming space that I can obtain?

Due to a combination of the memory-mapped I/O address spread all over the
lower 32K and compiler constraints, it won't do more than 32K.  In general,
tho, you *really* shouldn't worry about it until you compile your program
and find out if it's near the max.  The compiler is pretty tight, unlike
what you may be used to.

To change the situation would require 1) finer resolution of the I/O map and
2) reworking the compiler.  The first isn't too hard, but needs a few more
gates wedged on somehow (the spare gates onboard aren't enough) to shrink
the I/O map and generate a /CHIP_SELECT for the new SRAM, the second may be
a bunch of work (I haven't looked at the compiler).  Of course, if you want
to beat yourself over the head and do it all in ASSEMBLY, it just needs the
hardware hack.  You'll immediately have a custom system that'll never play
with anyone else's code, so most folks avoid it if possible.

