Event input using the evaluation board

Applicable receivers: BD940 | BD940-INS | BD970 | BD982 | BD990 | BD992 | BD992-INS

This topic describes how to condition and analyze event input signals when using the OEM GNSS I/O development boards. This knowledge also applies to the customers’ implementation of event inputs on their carrier board for the BD9xx.

Useful links:

For information about the web interface settings, see the topic, Receiver Configuration – General.
Application note: Event (0) 1PPS Input Example.
For Event 1 and Event 2 information, see below.

Event

Item	Description
Event 1	On the BD940 receiver module, pin 37 is dedicated as an Event_In pin. On the BD940-INS receiver module, pin 15 is dedicated as an Event_In pin. On the BD970 receiver module, pin 8 is dedicated as an Event_In pin. On the BD982 receiver module, pin 8 is dedicated as an Event_In pin. On the BD990 receiver module, pin 8 is dedicated as an Event_In pin. On the BD992 and BD992-INS receiver modules, pin 8 is dedicated as an Event_In pin. This is a TTL-only input; it is not buffered or protected for any inputs outside of 0 V to 3.3 V. It does have ESD protection. If the system requires event to handle a voltage outside this range, the system integrator must condition the signal before connecting to the unit.
Event 2	On the BD940 receiver module, pin 39 is dedicated as an Event_In pin. On the BD940-INS receiver module, pin 7 is dedicated as an Event_In pin. On the BD970 receiver module, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2. On the BD982 receiver module, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2. On the BD990 receiver module, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2. On the BD992 and BD992-INS receiver modules, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2. This is a TTL-only input; it is not buffered or protected for any inputs outside of 0 V to 3.3 V. It does have ESD protection. If the system requires event to handle a voltage outside this range, the system integrator must condition the signal before connecting to the unit.

Item

Description

Event 1

On the BD940 receiver module, pin 37 is dedicated as an Event_In pin.

On the BD940-INS receiver module, pin 15 is dedicated as an Event_In pin.

On the BD970 receiver module, pin 8 is dedicated as an Event_In pin.

On the BD982 receiver module, pin 8 is dedicated as an Event_In pin.

On the BD990 receiver module, pin 8 is dedicated as an Event_In pin.

On the BD992 and BD992-INS receiver modules, pin 8 is dedicated as an Event_In pin.

This is a TTL-only input; it is not buffered or protected for any inputs outside of 0 V to 3.3 V. It does have ESD protection. If the system requires event to handle a voltage outside this range, the system integrator must condition the signal before connecting to the unit.

Event 2

On the BD940 receiver module, pin 39 is dedicated as an Event_In pin.

On the BD940-INS receiver module, pin 7 is dedicated as an Event_In pin.

On the BD970 receiver module, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2.

On the BD982 receiver module, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2.

On the BD990 receiver module, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2.

On the BD992 and BD992-INS receiver modules, pin 7 is Event 2; however, it is multiplexed with COM3_RX and CAN_RX. The default setting is to have this line set to COM3_RX. The Event 2 must be enabled to use Event2.

Event schematics of the BD9xx evaluation PCB

Trimble recommends adding a Schmitt trigger and ESD protection to the Event_In pin. This prevents any "ringing" on the input from causing multiple and incorrect events to be recognized.

Event input using the evaluation board

Event

Event schematics of the BD9xx evaluation PCB

PPS output and event inputs BD940

PPS output and event inputs BD40-INS

PPS output and event inputs BD970 and BD982

PPS output and event inputs BD990, BD992, and BD992-INS