| 摘要 |
A microprocessor is provided with a reset logic flag and corresponding reset microcode that selectively enables the reset microcode to set up and enable debug logic before the microprocessor subsequently fetches and executes user instructions. When the reset logic flag is set to a debug mode, the reset microcode configures and enables the microprocessor's debug logic before the microprocessor subsequently fetches and executes user instructions. When the reset logic flag is set to a normal mode, the reset microcode refrains from configuring and enabling the microprocessor's debug logic. The reset logic flag is indicated by an alterable fuse or a debugger-programmable scan register. Debug configuration initialization values are also provided by several alternative structures, including the reset microcode itself, alterable fuses, and debugger-programmable scan registers. Corresponding methods are also provided for configuring the debug logic of a microprocessor.
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