| 摘要 |
An embedded system for preventing removal of a control circuit pack during programming of a flash memory. The embedded system includes a reset button to be pressed prior to unplugging the control circuit pack and an indicator for signaling when the control circuit pack may be safely removed or unplugged from a shelf. In the case in which the flash memory is uninterruptable, all of the interrupts, except for a power reset interrupt, are inhibited during programming of at least one block of the flash memory. Upon activating the reset button, if programming of the flash memory is completed, then the reset interrupt is invoked and an indicator is enabled thereby signaling that it is safe to remove the control circuit pack. Otherwise, if programming of the flash memory is in progress, then the reset interrupt, like all other interrupts, is inhibited. Alternatively, the flash memory may be interruptable. In this case the system also includes a timer interrupt invoked after a timer has completed a countdown of a predefined time interval. During programming predetermined interrupts that require processor time to the extent that exceeds the programming time required, excluding the reset interrupt and the timer interrupt, are inhibited. The reset interrupt is invoked upon pressing the reset button. In response to invoking the reset interrupt, if programming of the flash memory is in progress then the timer is set to countdown for the predefined interval and programming is resumed from the position of interruption. Completion of the timer countdown for the predefined time interval invokes a timer interrupt handler that continuously resets the timer to countdown for the predefined time interval, and upon completion of the countdown determines whether programming of the flash memory is in progress. The indicator is enabled when programming of the flash memory is no longer in progress at the completion of the countdown of a predefined timed interval.
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