To allow for synchronised record or replay by LabSat 2 the pause input pin is normally pulled high to 3.3 V. When this pin is driven to 0 V the LabSat 2 will pause the record or replay start until 3.3 V is restored. The pause function can be used to start record or relay in synchronisation with other devices. This feature can also be used to enable multiple LabSat 2’s to synchronise record and replay. The Advanced Recording Control and the Advanced Playback Control features can be set to further control GNSS device testing.
Digital Input /Output
The selection of the Channel A 1 bit + 2 Channel DIO in the Advanced Recording Control will allow recording of 3.3 V logic signals in synchronisation with the GPS-L1 signal. Since the extended digital inputs replace the GLONASS channel in the recorded data, it is not possible to record GLONASS signals at the same time as the extended digital inputs. Digital inputs are sampled at 16.368 MHz. Inputs are internally pulled up to 3.3 V and can be used to sample logic level serial data, synchronisation signals or for marking events. (see page 39. 26 Way D – Type Connector information)
The Digital I/O connector uses 3.3 Volt logic levels. Connection of any of the IO signals to levels above 3.3 Volts will cause permanent damage to the internal logic.