CSS CANedge2 - Log file; Organization; MDF

CANedge2 Docs, Release FW 01.04.02
Data
Data prescaling can be used to only accept messages when the data payload changes. A mask can be
set to only consider changes in one or more specific data bytes. The mask works on a byte level. The
mask is entered in hex up to 8 bytes long (16 hex characters). Each byte contains 8 bits, allowing for
the mask to be applied to any of the maximum 64 data bytes (CAN FD).
This prescaler type is useful if only changes in data or parts of the data are to be logged.
Examples of data masks:
• "": A empty mask triggers on any data change (equivalent to mask value FFFFFFFFFFFFFFFF)
• 1: Triggers on changes to the first data byte (binary 1)
• 2: Triggers on changes to the second data byte (binary 10)
• 3: Triggers on changes to the first or second data byte (binary 11)
• 9: Triggers on changes to the first or fourth data byte (binary 1001)
• FF: Triggers on changes to any of the first 8 data bytes (binary 11111111)
• 100: Triggers on changes to the 9th data byte (binary 100000000)
If the data payload contains more data bytes than entered in the mask, then changes to the additional
bytes are ignored by the prescaler.
Warning: Data prescaling assumes that a message with a specific ID always carries the same
number of data bytes
Example: A discretely changing signal is broadcasted every 100 ms (10Hz). A data prescaler is used
such that only changes in the signal are logged.
Example: Data prescaling applied to ID 800
10
with empty mask (all changes considered). D0-D3 is a
4-byte payload (with D0 the first data byte).
ID (DEC) D0 D1 D2 D3 Result
800
10
00 11 22 33 Accept
800
10
00 11 22 33 Reject
800
10
00 BB 22 33 Accept
800
10
AA BB 22 33 Accept
800
10
AA BB 22 DD Accept
800
10
AA BB 22 DD Reject
0.4. Configuration 31