Date and Real Time Clock Reference in Spectran | PPM

Quote from EngJR on 31/03/2021, 12:37

Data Time stamping is done with a precision 100MHz Clock.

1. In case GPS is not used, the PC date and time is synchronized with the 100MHz Clock. In order to improve Time stamping, the GPS option is used.
2. Spectran V6 has an PPS input which can be used to sync the internal 100MHz from an external source; typically from a GPS signal. However this is an input only, so no, you can not master from one Spectran V6 into multiple Spectran V6 slaves.

Quote from Prabhat on 31/03/2021, 14:01

If you are referring to PPM signal in the Spectran block diagram, then it is shown as bidirectional. Master can be OUTPUT configured and Slaves can be configured as INPUT. Is assumption correct?

Quote from EngJR on 31/03/2021, 14:41

Yes, this is how the hardware is build.

However, the output function is not available to the user. Switching between input and output by user control can permanently damage the device.

Next problem in your setup idea is to duplicate master ppm into multiple slave ppm without loosing performance. Additionally the software must identify master Spectran V6 and transfer date and time from master to the connected slaves too.

I refer to the PPM signal as PPS since it precisely outputs a rising edge every second.

Quote from Prabhat on 31/03/2021, 14:54

I expected this functionality based on the study of the Spectran Block Diagram (bi-directional PPM) and assumed that RTSA  Software will facilitate the transfer of necessary Date and Time configuration in the slave Spectrans.

I presume you are referring to user controlling PPM as output and damaging the Spectran may be due to more than one PPM being configured as output which can cause damage.

Is it not possible to configure only One as PPM Output and others as PPM input in the Spectran Stacking. This could be controlled/ checked by RTSA Software which configures Spectrans in a cluster.

Quote from EngJR on 31/03/2021, 18:04

Don't get me wrong: you point to a useful setup that the hardware could support. It is just a question to implement it in software and characterize this setup properly.

Quote from Prabhat on 01/04/2021, 07:57

So, I understand that PPS can be configured as output though, it may not have checks and controls when multiple Spectran are connected together  in the RTSA Software and therefore you are not recommending.

As an information I want to know the Fanout, driving capacity, of the PPM port signal, that is how many input PPM ports can be connected to one single PPM output port.

Quote from EngJR on 01/04/2021, 09:40

Spectran V6 PPM output is designed to drive CMOS compatible loads up to 20uA.