PORT A INTERFACE

WT) facility, which allows an external device to insert an arbitrary number of wait states when accessing either a single location or multiple locations of external memory or I/O space. Wait states are executed until the external device releases the DSP to finish the external memory cycle. An internal wait-state generator can be programmed using the BCR to insert up to15 wait states if it is known ahead of time that access to slower mem- ory or I/O devices is required. A bus wait signal allows an external device to control the number of wait states (not limited to 15) inserted in a bus access operation.

MOTOROLA

PORT A

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Motorola DSP56000, 24-Bit Digital Signal Processor manual Port a Interface