| 摘要 |
A method for signaling the type of access sought by a microprocessor to external memory. A microprocessor can read from or write into external memory. When the microprocessor initiates a read or write cycle, access signals indicating: the read or write cycle, the lower order address bits of the sought after code or data, whether code or data is sought, and bit-width of the sought after code or data, are provided to the inventions byte enable chaser circuit. If a read cycle has been initiated the byte enable chaser circuit encodes the signals into predetermined bit patterns and outputs the bit patterns on the microprocessor's byte enable signal pins. The bit-patterns are available for each bus cycle and specify whether code or data is sought, the length of the sought string, and the lower order address bits of the strings address. If a write cycle is initiated the byte enable signed pins indicate which byte(s) of the data bus are to be written into memory.
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