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■ BY PETER BEST
MORE FUN WITH FREESCALE’S
MICROCONTROLLERS
WELCOME BACK! Hopefully you’ve visited freescale.com, gotten yourself a
copy of the free Freescale Semiconductor CodeWarrior Development Studio
for HC08 v5.0., and you’ve built up your own MC68HC908MR16 MCU module.
All of the MC68HC908MR16
groundwork was done in the
previous installment of Design Cycle,
and we’ve got plenty of new
MC68HC908MR16 stuff to cover this
time around. So, be sure to download
all of the MC68HC908MR16 C project
files I’ve provided so you can follow
along live and in real-time with the
text and new MC68HC908MR16
projects I’m about to present. I’ll stop
flapping my jaws so we can get to
work. Let’s begin by bringing up the
MC68HC908MR16’s RS-232 serial port.
CODING AND
ACTIVATING THE
MC68HC908MR16
RS-232 PORT
Before we begin, I would like to
point out that when you see numbers
like “0x12345” in this text, the 0x
denotes hexadecimal representation.
A 0b preceding a string of 1s (ones)
and 0s (zeros) denotes a binary
representation of the number in the
spotlight. An “x” inside a binary or hex
number string represents a “don’t
care.” As you’ll see, I will use an “x” as
a place holder when I’m highlighting
certain bits in a binary number or set
of hex characters.
You’ll also want to go
ahead and download all
of the MC68HC908MR16
project files, as I’ll be referencing them as we go along.
You can get them from the
Nuts & Volts website (www.
nutsvolts.com) or from the
EDTP Electronics website
( www.edtp.com).
■ PHOTO 1. The Target CPU
window is very interesting.
I recommend that you
click around on its contents
to see where you are taken.
The Bean Drill consists of
choosing a Bean using the
Bean Selector, adding the
chosen Bean to the project,
and configuring the Bean
with the Bean Inspector.
FOR YOUR INFO
Listings 1-4 referenced in
this article are available on
the Nuts & Volts website.
Go to www.nutsvolts.com
26
March 2006