NavCom SF-2050 Rev.D - Manual (Page 24)

SF-2050 User Guide - Rev. D
1 PPS
The SF-2050M 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.
NavCom
P/N 94-310050-3003 provides a 0.9m (3ft)
long BNC male to BNC male connection.
CAN Bus/Event
The SF-2050M 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 SF-
2050M
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.
‡
As CAN Bus specifications are diverse, drivers for the
existing hardware must be tailored to the specific
manufacturer’s equipment being interfaced. For further
information on interfacing with the SF-2050M CAN Bus
hardware e-mail NavCom Customer Support at
[email protected] .
2-22