5 GPS180PEX Features
5.4 Pulse and frequency outputs
The pulse generator of the clock GPS180PEX contains three independent channels (PPO0, PPO1, PPO2).
These TTL outputs can be mapped to pins at the 9-pin connector at the rear slot cover by using a DIP switch.
The pulse generator is able to provide a multitude of different pulses, which are configured with the monitor
program. The active state of each channel is invertible, the pulse duration settable between 10 msec and 10
sec in steps of 10 msec. In the default mode of operation the pulse outputs are disabled until the receiver has
synchronized after power-up. However, the system can be configured to enable those outputs immediately after
power-up.
Synthesizer
The programmable pulse outputs are able to generates a frequency from 1/8 Hz up to 10 MHz synchronous to
the internal timing frame. The phase of this output can be shifted from -360
◦
to +360
◦
for frequencies less than
10 kHz.
The following modes can be configured for each channel independently:
Timer mode:
Three on- and off-times per day per channel programmable
Cyclic mode:
Generation of periodically repeated pulses.
A cycle time of two seconds would generate a pulse at
0:00:00, 0:00:02, 0:00:04 etc.
DCF77-Simulation mode:
The corresponding output simulates the DCF77 time telegram.
The time marks are representing the local time as configured by the user.
Single Shot Mode:
A single pulse of programmable length is generated once a day at a
programmable point of time
Per Sec., Per Min.
Per Hr. modes:
Pulses each second, minute or hour
Synthesizer
Frequency output 1/8 Hz up to 10 MHz
Time Codes
Generation of Time Codes as described in chapter
"Time Codes"
Status:
One of three status messages can be emitted:
‘position OK’:
The output is switched on if the receiver was able to
compute its position
‘time sync’:
The output is switched on if the internal timing is
synchronous to the GNSS-system
‘all sync’:
Logical AND of the above status messages.
The output is active if position is calculated AND the
timing is synchronized
Idle-mode:
The output is inactive
The default configuration for the pulse outputs is:
—————————————————————————————
PPO0:
Pulse each second (PPS), active HIGH, pulse duration 200 msec
PPO1:
Pulse each minute (PPM), active HIGH, pulse duration 200 msec
PPO2:
DCF77 Simulation
A TTL level master frequency of 10 MHz is derived from the TCXO. By default, this frequency is available only
at the 5 pin contact strip of the board.
GPS180PEX
Date: 28th March 2018
9
