Emulator support mode for disabling and reconfiguring timeouts of a watchdog timer
US6145103A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 1998 |
| Grant date | Nov 7, 2000 |
| Priority date | — |
| Expiry date | Apr 7, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/3648
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A microcontroller-based device according to the present invention provides a watchdog timer having an emulator support mode for disabling and reconfiguring time-outs. When the watchdog timer is placed in the emulator support mode, the watchdog timer is inhibited from counting. In a disclosed embodiment, the watchdog timer is inhibited from counting by deasserting a count enable signal. A watchdog time-out is thus prevented from occurring during the emulator support mode. Also, during the emulator support mode, the watchdog timer control register is writable, allowing the emulator to disable a watchdog timer, enable the timer, or program a new time-out value for the timer. The watchdog timer control register is writable regardless of the state of the enable bit of the timer. Further, in the emulator support mode, a watchdog timer current count becomes readable and writable at a predetermined register address above the watchdog timer control register subsequent to a write of a write key sequence to the watchdog timer control register. By writing and reading the predetermined register address location, the emulator is able to define and monitor a condition as the watchdog timer is app…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.