发明名称 |
Asynchronously accessing the program counter values of a data processing system by applying an independent clock on the latching and scan-chain circuits |
摘要 |
A processing system 2 is described including a processor unit 4 and a memory 6. Diagnostic hardware 10 within the processing system 2 includes a shadow PC register 12 that stores a shadow program counter value following the true program counter value held within a program counter register 8 of the processor unit 4. The diagnostic hardware 10 is responsive to a program counter request signal from an external diagnostic system 14 to transfer a program counter value into a scan chain 16 from where it can be returned to the diagnostic system 14. The operation of the processor unit 4 is independent of any of the diagnostic operations and so true real time operation of the system may be observed and de-bugged.
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申请公布号 |
US6598150(B2) |
申请公布日期 |
2003.07.22 |
申请号 |
US20010969158 |
申请日期 |
2001.10.03 |
申请人 |
ARM LIMITED |
发明人 |
WILLIAMS MICHAEL JOHN;MERRITT ANDREW JOHN |
分类号 |
G06F15/00;H03L7/00;(IPC1-7):H03L7/00 |
主分类号 |
G06F15/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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