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host can send delimiter text always if desired whether or not delimiter text is
enabled.
9. All command characters are small letters (easier to differentiate from numbers, ie. s5 vs
S5).
10. Commands are variable length.
11. Commands have CRC for error checking at the end of the command. The CRC is
calculated from all the ascii characters, starting with the sync and ending with the comma
before the CRC value. See section
B.1.7
for CRC calculation code.
12. Out of range or invalid values received by a slave returns a NAK. If a NAK is returned it
does not indicate that none of the command was acted on, it only indicates where there
was a problem detected. It is possible for part of a command to be processed and acted on
even though one data field was determined to be invalid and a NAK is returned. The NAK
message indicates where the first error was detected. If an ACK is returned then all
portions of the command were determined to be valid and were processed. See the NAK
command, section
B.1.9
.
13. A NAK response is not returned by a slave if the CRC is enabled and the slave determines
that the CRC was incorrect.
14. Commands are terminated by carriage return 0x0D and line feed 0x0A
15. Any chars between a CR-LF and @ are ignored.
16. This protocol is fully text-editor compatible.
17. No scientific notation allowed (i.e. 7.65e2 or 4.56E-1 are not allowed).
18. No signed numbers allowed, sign is inferred as: forward values are positive, reverse values
are negative, other values are positive (i.e. -2.54 or +3.75 are not allowed).
19.
The ‘no response’ time-out duration the host uses should not be less than 10ms in order
for the LT controller to have enough time to process commands.
20. The maximum length of any message (including text deliminters) should not exceed 1024
characters. Messages longer than 1024 bytes will result in a NAK response from the slave.
21. Slaves will not send a response to messages directed to the global address (device
address 00). All slaves on the network will perform the requested action if they properly
receive the command, however no response is sent
B.1.5 Unit Addressing (@AA.a)
Unit ID ‘AA’ Channel
ID ‘a’
Description
00
0
Directed to all units
01
0
Directed to unit 1
99
0
Directed to unit 99