Rabbit RCM2000, Руководство по началу работы

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24 RabbitCore RCM2000
•
A message reports “No Rabbit Processor Detected” in cases where the RCM2000 and
the Prototyping Board are not connected together, the wall transformer is not con-
nected, or is not plugged in. (The red power LED lights whenever power is connected.)
•
The programming cable must be connected to the RCM2000. (The colored wire on the
programming cable is closest to pin 1 on header J3 on the RCM2000, as shown in
Figure 4.) The other end of the programming cable must be connected to the PC serial
port. The COM port specified in the Dynamic C
Options
menu must be the same as the
one the programming cable is connected to.
•
To check if you have the correct serial port, select Compile , then Compile BIOS , or
type <Ctrl-Y> . If the “BIOS successfully compiled …” message does not display, try a
different serial port using the Dynamic C Options menu until you find the serial port
you are plugged into. Don’t change anything in this menu except the COM number.
The baud rate should be 115,200 bps and the stop bits should be 1.
4.3 Single-Stepping
Compile or re-compile
FLASHLED.C
by clicking the Compile button on the task bar. The
program will compile and the screen will come up with a highlighted character (green) at
the first executable statement of the program. Use the
F8 key to single-step. Each time the
F8
key is pressed, the cursor will advance one statement. When you get to the
for(j=0,
j< ...
statement, it becomes impractical to single-step further because you would have
to press
F8
thousands of times. We will use this statement to illustrate watch expressions.
4.3.1 Watch Expressions
Type <Ctrl-W> or chose Add/Del Watch Expression in the Inspect menu. A box will
come up. Type the lower case letter j and click on add to top and close . Now continue sin-
gle-stepping with F8 . Each time you step, the watch expression (
j
) will be evaluated and
printed in the watch window. Note how the value of
j
advances when the statement
j++
is
executed.
4.3.2 Break Point
Move the cursor to the start of the statement:
for(j=0; j<25000; j++);
To set a break point on this statement, type F2 or select Toggle Breakpoint from the Run
menu. A red highlight will appear on the first character of the statement. To get the pro-
gram running at full speed, type
F9 or select Run on the Run menu. The program will
advance until it hits the break point. Then the break point will start flashing and show both
red and green colors. Note that LED DS3 is now solidly turned on. This is because we
have passed the statement turning on LED DS3. Note that
j
in the watch window has the
value 32000. This is because the loop above terminated when
j
reached 32000.
To remove the break point, type F2 or select Toggle Breakpoint on the Run menu. To
continue program execution, type
F9
or select
Run
from the
Run
menu. Now the LED
should be flashing again since the program is running at full speed.