Operator's manual – Teledyne LeCroy CANbus TD and CANbus TDM - Operators Manual User Manual
Page 67
Operator's Manual
CANbus-TD-TDM-OM-E RevB
67
Data Value -- The Data Value is set in Hexadecimal format. If
you wish, you can precede the ID value with a “0x”, but this is
not necessary. Make sure to enter a Data Value that matches
the DLC Value. If you have set the Data Condition to INRANGE
or OUTRANGE, then you will enter two Data Values.
If you wish to set the Data Value in a Binary format, reference
the separate section on how to do this.
CAN data can be formatted in several different formats – MSB
(Most Significant Byte) or LSB (Least Significant Byte. In all
cases, bit data is lsb (least significant bit, bitwise to the left, or
the 7
th
bit in the byte appearing at the far left of the byte, and
the 0
th
bit at the far right of the byte).
The CAN controller used in the Trigger Module formats data in
MSB and lsb (bitwise to the left) format.
Note: The decoding algorithm always decodes the CAN signal
(in hexadecimal nibbles and bytes) using an LSB and lsb
condition.
Start Bit and # Bits -- The CANbus TD trigger allows you to
trigger on up to 24 contiguous data bits (3 data bytes). This
maximum 24-bit string can start at any location in the CAN
message data field --- it is not limited to the start of a full byte
or a nibble.
The Start Bit can be any value from 0 to 63. If you enter a value
less than 0, it will default to 0. If you enter a value more than
63, it will default to 63. The Start Bit value is always in LSB
format (i.e., the bit number as shown on the decoded
waveform, with bit 0 being at the far left and bit 63 being at the
far right of the data string). Remember that the 1
st
data byte is
bits 0-7, the 2
nd
data byte is bits 8-15, etc. Also, make sure that
your Start Bit value makes sense in relation to the DLC Value.
For instance, a Start Bit value of 32 with a DLC Value of 4 is not
going to result in a successful trigger.
Reference the Trigger Setup Examples section for more
information on setting up a trigger where the start bit is not the