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There are two Advanced Peripheral Bus (APB) timer modules that are instantiated within the subsystem hierarchy in Cortex®-M3 DesignStart™ Eval.
These APB timers are reserved for the operating system. ARM recommends that you do not modify these timers or their connections to the subsystem.
For more information on the subsystem in Cortex-M3 DesignStart Eval, see the ARM® Cortex®-M3 DesignStart™ Eval RTL and Testbench User Guide.