8.3.14 Interrupt Signals

The DS250DF810 can be configured to report different events as interrupt signals. These interrupt signals do not impact the operation of the device, but merely report that the selected event has occurred. The interrupt bits in the register sets are all sticky bits. This means that when an event triggers an interrupt the status bit for that interrupt is set to logic HIGH. This interrupt status bit will remain at logic HIGH until the bit has been read. Once the bit has been read it will be automatically cleared, which allows for new interrupts to be detected. The DS250DF810 will report the occurrence of an interrupt through the INT_N pin. The INT_N pin is an open drain output that will pull the line low when an interrupt signal is triggered.

Note that all available interrupts are disabled by default. Users must activate the various interrupts before they can be used.

The interrupts available in the DS250DF810 are:

• CDR loss of lock
• CDR locked
• Signal detect loss
• Signal detected
• PRBS pattern checker bit error detected
• HEO/VEO threshold violation

When an interrupt occurs, share register 0x08 reports which channel generated the interrupt request. Users can then select the channel(s) that generated the interrupt request and service the interrupt by reading the appropriate interrupt status bits in the corresponding channel registers. For more information on reading interrupt status, refer to the DS250DF810 Programming Guide.