Trimble Outdoors r7 Manuale Utente

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1 1       Event Marker Input and 1PPS Output
1 0 2      Trimble R7/R8 GPS Receiver User Guide
Tr
imble R7 Operation
11.1
1PPS Output
The Trimble R7 receiver can output a one pulse per second (1PPS) 
time strobe with an associated ASCII time tag output. The pulse is 
output through Port 2 of the receiver using the event marker/1PPS 
cable. 
111.1
1PPS pulse definition
The leading edge of the pulse coincides with the beginning of each 
UTC second, as shown in Figure 11.1. The pulse is driven by an 
RS-422 driver between nominal levels of 0 V and 4 V. The leading 
edge is positive, rising from 0 V to 4 V.
Figure 11.1
Time tag relation to 1PPS wave form
0 V
4 V
Seconds
Time tag output here
Time tag applies here