Microchip Technology SA5 Series, User Manual

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MAC-SA5X USER’S GUIDE
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2019 Microchip Technology Inc. DS50002938A-page 29
Chapter 4. Command Line Interface
This section describes the communication interface provided by the Microchip MAC
SA5X Rubidium Oscillator. The device supports the Microchip proprietary C3 protocol.
The C3 protocol provides read/write access to the device’s parameters. The device’s
state is exposed through these parameters; modifying their values produces changes
in state. The C3 protocol also provides access to flash memory operations, device
identification functions, and device telemetry.
Key Features
Key features of the C3 protocol include:
• Text-based: Compatible across many architectures; avoids number representa-
tion issues.
• Orthogonal: All commands and responses share the same format.
• Parameter-based: Command set is based on exposing information and controls
as a set of parameters.
• Error-detecting: With checksums, garbled commands/responses are more detect-
able.
Message Flow
For each command message sent to the device, one response message will be
returned. In certain situations, such as device startup, announcement messages are
sent asynchronously.
Note: Protocol is character case-sensitive.
4.1 COMMAND STRUCTURE
The structure of a C3 command follows:
{command#XX,argument1,|CC}
Where:
TABLE 4-1: COMMAND STRUCTURE
Field Description Required?
{
Signifies the beginning of a command. Yes
command
The name of the command being issued. Yes
#XX
The sequence number of the command. (XX = two hex dig-
its).
No
,argument1
The start of the argument list, beginning with a comma and
containing quoted or un-quoted arguments.
Per Command
|CC
The 8 bit checksum of the command message. (CC = two
hex digits).
No
}
Signifies the end of a command. Yes
The sequence number, arguments, and checksum fields are optional. If a command is
entered incorrectly, MAC will reply with the appropriate error message (See
Section 4.2.1 “Error Responses” ).