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questions (about x21)


I'm pretty new to electronics engineering, but I've been following MISC
stuff for a while...what I want to do is make a protable x21 (probably P21
since it is easily obtainable in convenient DIP packaging) box.  By portable
I mean that it has to fit in my pocket.  I want to use it to log body
sensors (ultimately I want to take an EEG), respond to a simple input
device (two metal bars, one at +5V, one at -5V, on my left arm...on my
right hand a glove with metal tips going to appropriate
diodes/buffers/etc), and uotput through what will probably end up being
one of those simple serial 40x4 text LCDs.  I'm a big fan of FORTH (though
an inexperienced FORTH programmer...I'm too tied to Unix/C for professional
work), and all of the chips (except x21) I've seen look like they'd be pretty
stupid for this use (I can't stand implementing Forth on stupid architectures
like x86...the m68k looks attractive because of its uniformly simple
address register use -- like it was made for multiple stacks, but P21
looks even sexier).  I was briefly interested in the PTSC1000, but it's
only available in PQFP, which I don't think I can reasonably use (I suck
at soldering...I don't want to even try surface-mount).
	So my question is: can I reasonably wirewrap up a board with the
P21?  I don't know much about the relevant issues, but I get the
impression that going above 10MHz with wirewrap is just begging for
trouble.  I don't need much RAM and I want to keep everything as simple
(and low power...I'm contemplating powering it off of my own movements,
so no DRAM for me...I might even forego EPROM and have it only bootable
when connected to one of my other computers to download the bootcode)
as possible, so I don't think any of the existing boards will do what I'm
looking for.  I don't care much about performance, so on any other chip
(like the PTSC1000), I'd just run the clock lower, but I get the
impression that the P21 doesn't have a clock per se.  What do I need to do
(is my concern even justified?) to make sure that the P21 won't have
troubles talking to its RAM (which will be at most the width of two chips
away) from crosstalk/capacitance/whatever?
	Also, I want more concrete details on the P21.  I suspect C.H.
Ting's MuP21 Programming Manual has what I'm looking for.  While I don't
mind paying for the thing, I would like to have something to read before I
order everything.  I'm a college student and $50 is still enough money that
I'd like to at least do some research before shelling out the cash.  I'm
looking for instruction set summary, pinout, maybe current draw info,
etc., just so I can get a feel for the chip.  If this information is
already out there (it seems like it should be, since there's that type of
info for the F21 already) then if soomeone could point me to it, that'd
be greatly appreciated.

Thanks!