GridConnect CAN USB-232, User Manual

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Getting Started
CAN USB-232 User Manual 2-49
In configuration mode:
To enable: set timestamp enable=yes
To disable: set timestamp enable=no
To determine the current state of timestamp enable: get timestamp
This will return a string with the enable status: Ex: <A:enabled=yes>
Note: commands are not case sensitive.
CAN RX Message Format Changes (when timestamping is enabled):
ASCII Mode :
In ASCII mode, the timestamp is appended to the data block in uppercase HEX ASCII in the same way that
the data field is presented (i.e.: two ASCII HEX digits to represent a byte). The '@' character is inserted
between the last DATA digit and the first TIMESTAMP digit to differentiate between the two fields.
Zero-length messages appear as they would normally, except the prefixed timestamp is added.
Ex 1:S12N12@F00F: This is a 11-bit identifier with 1 data byte and timestamp of $F00F ms.
Ex 2:X13N@2EDF: This is a 29-bit identifier with 0 data bytes and timestamp of $2EDF ms.
Ex 3:S14R5@15E5: This is a 11-bit identifier with RTR=5 and timestamp of $15E5 ms.
In short, the timestamp is always prefixed with a '@' character.
The timestamp is variable length from 1 digit to 4 digits (uppercase ASCII HEX).
BINARY Mode:
In binary mode, the received CAN messages are extended by appending the time-stamp as two binary bytes
(MSB first).
The encoding of the two byte is the same as for the DATA field (i.e., If any of the time-stamp bytes is a
synchronization character, it is escaped).
The time-stamp field is always two logical bytes, but can be expanded up to four in the case where both
MSB and LSB bytes are synchronization characters.
2.12.1 get timestamp