36
Fox (LP3500)
A program “runs” in either mode, but can only be downloaded and debugged when the
LP3500 is in the Program Mode.
Refer to the Rabbit 3000 Microprocessor User’s Manual for more information on the pro-
gramming port and the programming cable.
3.9.2 Standalone Operation of the LP3500
The LP3500 must be programmed via the Prototyping Board or via a similar arrangement
on a customer-supplied board. Once the LP3500 has been programmed successfully,
remove the serial programming cable from the programming connector and reset the
LP3500. The LP3500 may be reset by cycling the power off/on or by pressing the RESET
button on the Prototyping Board. The LP3500 module may now be removed from the Pro-
totyping Board for end-use installation.
CAUTION: Disconnect power to the Prototyping Board or other boards when removing
or installing your LP3500 to protect against inadvertent shorts across the pins or dam-
age to the LP3500 if the pins are not plugged in correctly. Do not reapply power until
you have verified that the LP3500 is plugged in correctly.
3.10 Other Hardware
3.10.1 Spectrum Spreader
The Rabbit 3000 features a spectrum spreader, which helps to mitigate EMI problems. By
default, the spectrum spreader is on automatically, but it may also be turned off or set to a
stronger setting. The means for doing so is through a simple global macro as shown below.
NOTE: Refer to the Rabbit 3000 Microprocessor User’s Manual for more information
on the spectrum-spreading setting and the maximum clock speed.
1. Select the “Defines” tab from the Dynamic C Options > Project Options menu.
2. Normal spreading is the default, and usually no entry is needed. If you need to specify
normal spreading, add the line
ENABLE_SPREADER=1
For strong spreading, add the line
ENABLE_SPREADER=2
To disable the spectrum spreader, add the line
ENABLE_SPREADER=0
NOTE: The strong spectrum-spreading setting is not recommended since it may limit
the maximum clock speed or the maximum baud rate. It is unlikely that the strong set-
ting will be used in a real application.
3. Click OK to save the macro. The spectrum spreader will now be set to the state specified
by the macro value whenever you are in the project file where you defined the macro.