In spite of occasional diversions, such as underwater navigation, I am
still keeping my eye on the ball and attempting to move right along with
mastering the PIC mystic.

The current project is to figure out how to do UART stuff (trying to master
PIC stuff apparently means going down what seems to be an infinite number
of branches off the main trunk).  Along this line, I got a file which goes
by the name of PICUART.ASM, written by one Thomas McGahee.  It is a good,
informative program on learning how to use the UART feature, with many,
many comments.  I find it extremely useful.

However, it does not do a one-to-one mapping to the 18F452 chip (it is
written for the 16C74A), which is no big problem.  A few assembly errors,
easily fixed.

But it does raise one interesting question.  He emphasizes -- strongly --
that the  two i/o pins for uart use (RC7 receive, RC6 transmit) must both
be set to 1 (for input).  His exact words, possibly paraphrased but not
with evil intent, are: "rc7 input, rc6, actually an output but MUST be
programmed as input."

Well, this is all well and good, and I bow to experience, except that the
18F452 datasheet, which I have a certain amount of trust in, says (page
165) that rc7 must be input (1) and rc6 must be set to output (0).

Anyone know which is correct??

John

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