The output subsystem provides time code and frequency references derived from the input reference. The outputs provided include a single IRIG AM and DCLS output pair, a 10-MHz sine wave output, and a 1PPS output.
The output subsystem supports setting output offset(s) for each output except the 10-MHz sine wave output, which can be used to compensate for output cable length delays or downstream clock accuracy errors. Each output offset can range from -500 msec to +500 msec in 5 or 20-nsec steps (depending on the type of output).
The TSync Time Code Processor card provides one IRIG AM and DCLS pair output. The IRIG output is a rolling count of the initial value of the system time until synchronized. The card drives the IRIG AM output from an associated IRIG DCLS output and outputs the exact same format (except for the AM modulation).
The TSync Time Code Processor card supports IRIG outputs with Formats A, B, E and G. It also supports IRIG outputs using modulation frequency values of pulse width code, also known as DCLS, and sine wave amplitude modulated coding. It further supports IRIG outputs with frequency/resolution values of no carrier/index count interval, 100 Hz/10 ms, 1kHz/1ms, 10 kHz/0.1 ms, and 100 kHz/10 ms. Coded expressions for the fields BCDTOY, CF, SBS, and BCDYEAR. Are supported, as is IRIG output for the following coded expressions combinations for BCDTOY, CF, SBS, and BCDYEAR fields:
- 0 – BCDTOY, CF, SBS
- 1 – BCDTOY, CF
- 2 – BCDTOY
- 3 – BCDTOY, SBS
- 4 – BCDTOY, BCDYEAR, CF, SBS
- 5 – BCDTOY, BCDYEAR, CF
TSync Time Code Processor cards allow the user to select the following Time Code Formats for IRIG output:
IRIG Output Reference Formats
|A – DCLS||A – AM||B – DCLS||B – AM||E – DCLS||E – AM||G – DCLS||G – AM|
TSync Time Code Processors allow the user to select the IRIG B variant NASA36 as an IRIG output. It also supports user-selection of IEEE C37.118-2005 as an IRIG output. This is an IRIG B format with extensions. The card is compliant with IEEE 1344-1996 as IEEE C37.118-2005 supersedes this specification.
The card generates the non-standard IRIG formats that are generated by the Spectracom Netclock, including the non-standard BCDYEAR. This provides for compatibility with existing Spectracom NetClock products.
Note: Configuration of IRIG parameters should always be in the following order: format, coded expressions, control field definitions.
TSync Time Code Processor cards support adjustment of the IRIG output amplitude using a scale ranging from 0 to 255, with 128 being the middle and default value. The adjustment range approximates a linear function.
The IRIG outputs provide an offset that can be applied to adjust its relationship with the internal system 1PPS, from -500 msec to +500 msec in 5-nsec increments
The IRIG outputs provide signature control, which enables and disables outputs under the following conditions:
- Signature control off — outputs always on.
- Signature control enables output when in sync to input reference only
- Signature control enables output when in sync to input reference or in holdover.
TSync Time Code Processor cards generate a digital 1PPS output from the internal 1PPS of the system. Several parameters of the 1PPS can be controlled. The active edge can be set to either rising or falling edge, the pulse width can be adjusted, and an offset can be applied to adjust its relationship to the internal system, 1PPS from -500 msec to +500 msec in 5nsec increments. The 1PPS output provides signature control similar to the IRIG outputs.