Generator detecting internal and external ready signals for generating a bus cycle end signal for microprocessor debugging operation
AssigneeNEC Corporation
InventorMasahiro Shouda
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AssigneeNEC Corporation
InventorMasahiro Shouda
Estimating the term…
In a debugging microprocessor having a function of elongating a bus cycle in response to an external ready signal and used in a microprocessor development support system having a function capable of tracing and analyzing the result of execution, there is provided a generator for generating a bus cycle end signal for the microprocessor development support system. The generator comprises a ready detection circuit receiving an external ready signal, a clock signal and an enable signal which is rendered active only when the debugging microprocessor is in a condition capable of accepting data. The ready detection circuit operates to detect the status of the external ready signal at a time defined by a clock appearing when the enable signal is active, so as to generate an internal ready signal if the external ready signal is active. A control circuit is connected to receive the internal ready signal for generating a signal indicative of an end of the bus cycle for a predetermined period of time starting from a next clock state. This bus cycle end signal is outputted to an external device or stage of the debugging microprocessor.
In a debugging microprocessor, in a microprocessor development support system, for elongating a bus cycle in response to an external ready signal from an external device which is accessed by a data access request from said debugging microprocessor, said external ready signal indicating that said external device has prepared data to be supplied to said debugging microprocessor, said debugging microprocessor tracing and analyzing the result of execution of instructions by said debugging microprocessor, a generator comprising:
A microprocessor for executing a bus cycle in response to an external ready signal from an external device which is accessed by a data access request from said microprocessor, said external ready signal indicating that said external device has prepared data to be supplied to said microprocessor, comprising:
Dependencies are inferred from the claim text.