Rabbit 2000 Getting Started Manual - page 9
Getting Started Manual
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digital I/O cables. Your results may vary, depending on your application, so additional
shielding or filtering may be needed to maintain the Class B emission qualification.
NOTE: If no ferrite absorbers are fitted, the Jackrabbit boards will still meet
EN55022:1998 Class A requirements as long as the spectrum spreader is turned on.
The spectrum spreader is on by default for the Jackrabbit model BL1810 included with the
Rabbit 2000 Development Kit.
1.4.1 Spectrum Spreader
Jackrabbit 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 Jackrabbit BL1810 boards that carry the CE mark when
used with Dynamic C 7.32 or later versions so as to maintain CE compliance, but the spec-
trum spreader may also be turned off or set to a stronger setting. The means for doing so is
through a simple change to the following BIOS line.
#define ENABLE_SPREADER 1 // Set to 0 to disable spectrum spreader
// 1 to enable normal spreading, or
// 2 to enable strong spreading.
NOTE: The strong spectrum-spreading setting is not needed for any Jackrabbit board.
There is no spectrum spreader functionality for Jackrabbit boards that do not carry the CE
mark or when using any Jackrabbit with a version of Dynamic C prior to 7.30.
1.4.2 Design Guidelines
Note the following requirements for incorporating the Jackrabbit series of single-board
computers into your application to comply with CE requirements.
General
•
The power supply provided with the Development Kit is for development purposes
only. It is the customer’s responsibility to provide a CE-compliant power supply for the
end-product application.
•
When connecting the Jackrabbit single-board computer to outdoor cables, the customer
is responsible for providing CE-approved surge/lightning protection.
•
Rabbit Semiconductor recommends placing digital I/O or analog cables that are 3 m or
longer in a metal conduit to assist in maintaining CE compliance and to conform to
good cable design practices. Rabbit Semiconductor also recommends using properly
shielded I/O cables in noisy electromagnetic environments.
•
When installing or servicing the Jackrabbit, it is the responsibility of the end-user to use
proper ESD precautions to prevent ESD damage to the Jackrabbit.