Microsemi / Symmetricom / Datum bc635PCI / bc637PCI Time and Frequency Processor
Features
- PCI Local Bus Operation
- GPS or Time Code Inputs
- Translator Reads IRIG A, IRIG B and NASA 36
- External Event Capture Register / Interrupt
- IEEE 1344 Compliant IRIG B Time Code
Description
The Symmetricom / Bancomm / Datum bc635/637PCI receiver module provides precision time and frequency reference to the host computer system and peripheral data acquisition systems. Time is acquired from either the GPS satellites using a supplied antenna/receiver (bc637PCI only) or from time code signals, typically IRIG B.
Central to the operation of the module is a disciplined 10 MHz oscillator and 100 nanosecond clock. Current time (days to 100 nS) can be accessed across the PCI bus with zero latency, which allows for very high speed time requests. The onboard oscillator is rate-matched (disciplined) to the input time source and drives the precision 10 MHz frequency output and time code generator circuitry. If time is lost, the module will continue to maintain time (flywheel). If power is lost, a 10 PPM battery backed clock is available to maintain time.