1 pps, Can bus/event – NavCom RT-3020 Rev.A User Manual
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RT-3020S User Guide
The
GPS
LED
s will blink at the positioning rate
selected (1, 2, 5, 10 and 25 Hz).
1 PPS
The RT-3020M has the ability to output a precise pulse
every second with a relative accuracy to within 12.5ns,
and an absolute accuracy better than 100ns. The 1
PPS
is 50-Ohm, TTL level. By using the appropriate NavCom
proprietary command
, the 1
PPS
pulse width is user
configurable between 0.01 and 0.50 seconds, with the
default width set to 0.10 seconds. The delay default is
set to 0.0 seconds from the
GPS
zero second mark and
is configurable between 0.0 seconds and 0.999
seconds. This precise pulse can be used for a variety of
time mark applications where precise timing is a must.
The 1
PPS
pulse is user configurable to sync on the rising
or falling edge of the pulse. Connecting the 1
PPS
output requires a cable with a BNC male connector.
P/N
94-310050-3003 provides a 0.9m (3ft) long BNC
male to BNC male connection. Detailed specifications
of this pulse can be found on the NavCom website at
CAN Bus/Event
The RT-3020M also employs
CAN Bus
technology.
CAN
bus is a balanced (differential) 2-wire interface, and is
ISO11898 -24V compliant. The
CAN
interface uses an
asynchronous transmission scheme. This interface
employs a serial binary interchange and is widely used
in the automotive industry. The data rate for the RT-
3020M
CAN Bus
is defined as 250K
bps
maximum.
Termination resistors are used at each end of the cable.
This port/connector is shared with the
Even
t Input.
Detailed specifications of the
CAN
Bus
can be found on
the NavCom website at
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