User manual

Tamarisk
®
320
Software ICD
9
Acknowledgement (ACK) 0x02
Data filed includes16-bit command ID of the serial
command that is being acknowledged
Not acknowledged (NAK) 0x03
Data filed includes 16-bit command ID of the serial
command that is being unacknowledged
Error (ERR) 0x04
Data filed include 16-bit command ID of the serial
command that is in error
16-bit integer return value
(VALUE)
0x45 16-bit integer value broken up into 2 bytes
CMD Cmd Returns command code with response data
2.3.1 TXT Response
The TXT (Text) response provides feedback in human-readable form. The TXT message
contains an ASCII string of arbitrary length (the entire message must be less than the MTU
size). The connected unit may display the ASCII text as it sees fit or may discard the
information.
Table 3–TXT Response Format
Byte Value/Type Description
1 0x01 Start of message.
2 0x00 TXT Response ID.
3 N Number of text bytes to follow.
4 to
(N+3)
ASCII chars ASCII text. Null termination not required.
(N+4) checksum Frame check sequence. See paragraph 2.1.
Table 4 –Example TXT Response
Byte Value/Type Description
1 0x01 Start of message.
2 0x00 TXT Response ID.
3 0x06 Text message contains 6 characters.
4 to 9
0x48 (“H”)
0x6F (“o”)
0x77 (“w”)
0x64 (“d”)
0x79 (“y”)
0x21 (“!”)
ASCII text (“Howdy!”)
10 checksum Frame check sequence. See paragraph 2.1.
2.3.2 ACK Response
The ACK response is a general-purpose acknowledgement that a command has been
received. Some commands will result in two ACK messages – one generated upon receipt