Microchip Technology SA5 Series, User Manual

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Note: Spaces are not used within the command structure.
MAC-SA5X User’s Guide
DS50002938A-page 30

2019 Microchip Technology Inc.
4.1.1 Sequence Number
The optional sequence number is used to match a response to an earlier command.
Commands issued with a sequence number between #01 and #FF will trigger a
response message that includes the same sequence number.
4.1.2 Arguments
The argument list follows the command name (or the sequence number, if included),
and always begins with a comma before each argument. Numbers and alphanumeric
arguments can be written as-is, but arguments that may contain punctuation should be
enclosed in double quotes to prevent ambiguity when parsing the command.
Within a quoted argument, the backslash character is a special escape character. It can
be used to escape the following sequences (Any other sequences result in the removal
of the backslash.):
TABLE 4-2: ESCAPE SEQUENCES
Escape Sequence Resulting Character
\r
Carriage return.
\n
New line/line feed.
\t
Horizontal tab.
\\
Backslash.
4.1.3 Command Checksum
An optional 8-bit checksum provides a measure of reliability to commands and
responses. If a checksum is included with a command, the response will also include
a checksum for verification purposes.
The checksum of a command is calculated as a running XOR of all the characters
between the opening ‘{‘ and the ‘|’ checksum delimiter. It is a two-byte ASCII represen-
tation (in hexadecimal) of the XOR.
{command#XX,argument1,”argument2”|CC}
For example, the hexadecimal checksum of the
{device?}
command would be
entered as:
{device?|27}
If the command is garbled in transmission, causing a mismatch between the contents
and the checksum, the C3 response will be
[!3]
indicating a bad checksum error (See
Section 4.2.1 “Error Responses” ). The command should be re-sent.
4.2 RESPONSE STRUCTURE
The structure of a C3 response follows:
[#XX=value|XX]<CR><LF>
Where:
TABLE 4-3: RESPONSE STRUCTURE
Field Description Usage
[
Indicates the start of a response. Always