Rabbit BL2020, User Manual

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User’s Manual 33
3.9.3 Spectrum Spreader
BL2000 boards that carry the CE mark have a Rabbit 2000 microprocessor that features a
spectrum spreader, which helps to mitigate EMI problems. By default, the spectrum
spreader is on automatically for BL2000 boards that carry the CE mark when used with
Dynamic C 7.32 or later versions, but the spectrum spreader may also be turned off or set
to a stronger setting. The means for doing so is through a simple configuration macro as
shown below.
There is no spectrum spreader functionality for BL2000 boards that do not carry the CE
mark or when using any BL2000 with a version of Dynamic C prior to 7.30.
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 unnecessary for the BL2000.
3. Click OK to save the macro. The spectrum spreader will now remain off whenever you
are in the project file where you defined the macro.