Initialization/Application Information - Freescale Semiconductor MCF54455 Reference Manual

Crossbar Switch (XBS)
15.5.1.3 Priority Assignment
Each master port needs to be assigned a unique 3-bit priority level. If an attempt is made to program
multiple master ports with the same priority level within the priority registers (XBS_PRSn) the crossbar
switch responds with a bus error (refer to Section 14.2.5, "SCM Interrupt Status Register (SCMISR)") and
the registers are not updated.
15.6

Initialization/Application Information

No initialization is required by or for the crossbar switch. Hardware reset ensures all the register bits used
by the crossbar switch are properly initialized to a valid state. Settings and priorities should be
programmed to achieve maximum system performance.
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