User manual

CANbus Trigger, Decode, and Measure

CANbus-TD-TDM-OM-E RevB

Appendix A: External Trigger Hardware

CANbus TD Standard Hardware

The Standard Hardware consists of the following items:

Qty. 1: Trigger Module -- The Trigger Module is basically a

CAN Node that is set to filter (and provide a triggering

signal) when certain conditions are met. It contains a 32-

bit, 64 MHz microcontroller and two Philips SJA1000 CAN

controllers. A Trigger Coupler (CAN transceiver) needs to

be installed in the trigger module to connect to the

appropriate bus. A 251 Trigger Coupler is provided

standard on input 1, and a second can be installed on input

2. As necessary, the trigger couplers can be interchanged

to suit your specific needs. The Trigger Module receives

triggering instructions, as defined in the CAN Trigger dialog,

through the USB2.0 cable (connected to the LeCroy

oscilloscope), and outputs a trigger pulse through the 3-pin

connector when the CAN trigger condition is met. The

trigger pulse is a negative going edge from 5 V to 0 V.

Qty. 1: Oscilloscope Interface Module -- This module

connects to the Trigger Module via the 3-pin connector.

The module is LeCroy ProBus

compatible. When plugged

into a LeCroy oscilloscope, it is automatically recognized

and proceeds with appropriate setup for CAN triggering.

The OIM can be connected to any channel, but is more

commonly connected to the EXT input (to reserve a channel

for an analog signal). Once connected, it sets the following:

 sets the oscilloscope trigger to a negative going Edge

with a trigger level of 3 V (to trigger on the output

pulse when the CAN trigger condition is met) and no

trigger holdoff condition.

 displays the CAN trigger dialog

 applies a skew correction to all channels (to ensure

that the trigger point aligns with the EOF point of the