Debugging microprocessor capable of switching between emulation and monitor without accessing stack area
US4924382A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 5, 1988 |
| Grant date | May 8, 1990 |
| Priority date | — |
| Expiry date | Oct 5, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/3648
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A debugging microprocessor used in an in-circuit emulator is made to be capable of moving into a debugging interrupt processing execution mode in response to an external supervisor interrupt instruction. This debugging microprocessor comprises a first program counter put in an operating condition when the microprocessor is in a user's program execution mode, a second program counter put in an operating condition when the microprocessor is in a debugging interrupt processing execution mode, and a program counter controller responding to the external supervisor interrupt instruction to cause a content of the second program counter to be outputted as a program counter value. The program counter controller also responds to a return instruction to cause a content of the first program counter to be outputted as a program counter value. Thus, the content of the first program counter can be accessed in the course of the debugging interrupt processing execution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.