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Re: Questions


Dave Lowry wrote:
> Andrew-
> I hope you didn't misunderstand the tone of my posting about Jeff.  I surely
Not at all.

> didn't mean to chastise anybody for asking questions.  It's just that in the
> past folks have bitched about the P21 documentation (which *is* very poor),
> not realizing that Fox, Ting, & Moore are just 3 guys doing this work in
> their spare time, funded out of their own pockets.
And also using spare time to generate documentation, which I know can
get really boring (I personally know this from trying to document even
short programs that I write.)  And the documentation is actually not
that bad once you realize that some of it is simply prototype-chip info
and can be ignored (like the "MuP21 programmable memory interface",
which doesn't exist, but will exist on the F21.)  At first I was really
confused not so much because of the docs, but because the P21 is sooo
unorthodox.  (Which of course is a GOOD thing.)  The mechanisms for
accessing slow/fast rom & i/o, switching between dram/nondram address
spaces, & the fact that ALU operations are complete even before the ALU
knows what it's supposed to be doing all threw me for a loop, not to
mention the complementary bus interface.  I think I've got them figured
out now, and I feel especially dumb for ever being confused by the bus
interface to begin with.  It's simple.

> I just wanted to give Jeff a public pat on the back for helping us all out.
Indeed, and much deserved.

> Best of luck with your circuit board!
Thanks.  I've discovered that Easytrax's "autorouter" feature takes such
bizzare routes between pads that it's essentially useless.  I'm one of
those naive users who actually thought that the autorouter would save me
some time.  Oh well.

--Andrew