iXBlue GAPS - Synchronization Signals; Serial Link Wirings

GAPS - User Guide
2.2.3.7 Synchronization Signals
SYNC OUT
The two SYNC OUT connectors are called MAIN and SECONDARY. Responder mode signal
is sent to the transponder only if the responder mode is requested.
● Type: Differential
● Levels: 0 / +4.5 V
● Signal +: 0 / +4.5 V active high (0 / 2 V minimum if charge is 50 Ω)
● Signal -: 0 / +4.5 V active low (0 / 2 V minimum if charge is 50 Ω)
● Pulse length: 9 to 11 ms
SYNC IN
The two SYNC IN connectors are called PPS and TRIGGER. The external triggering signal is
an active high pulse. The GAPS is triggered on the rising edge.
● Type: TTL
● Levels: 0 / 5 V in standard mode (maximum level 10 V) active high, rising edge
● Length up to 35 µs (10 V, peak to peak) with flashing LED
● Length up to 1 µs (6 V, peak to peak) without flashing LED
● For the PPS input: configurable via the Web-based User Interface for the rising edge.
The LED flash is a copy of the incoming signal. If short PPS pulses are used, the LED may
not flash but this doesn’t mean that the system is not detecting the signals.
If GAPS is triggered in responder mode from the outside, with a transponder in responder
mode triggered on the sync IN input (the triggering pulse length must be higher than 5 ms), the
synchro shift between the recurrence and the transponder lasts 100 µs maximum. For this
reason, it is strongly recommended to trigger the transponder on the Sync OUT.
External GPS
An optional external GPS may be connected to the external optional GPS message input
serial link. Baud rate, parity and bit stop are adjustable from the Web-based User Interface.
The message expected by GAPS is the standard NMEA $GPGGA message and GPZDA is
automatically taken into account for the update of the GAPS internal time if available.
In case of an external GPS, the Y cable MUST NOT be used.
2.2.3.8 Serial Link Wirings
The four serial links are compatible with RS232 and RS422/485 protocols. The RS422/485
link is a simplex link working only in input or output. The wiring of the connectors is:
Pin / Protocol RS232 RS422 / 485
1 Tx+
2 Tx+ Tx-
3 Rx+ Rx+
4 Rx-
5 Ground
MU-GAPS-AN-005-H - November 2019 35