Confidential
Page 7
Serial Command Protocol
The host communicates with the MMXI controller via serial commands sent over RS232. All
commands should be terminated with a carriage return or semicolon character. If the command
fails parsing, the MMXI controller will return a question mark followed by a carriage return to
indicate a general syntax error. If the command parses correctly but fails to execute successfully
for any reason, the MMXI controller will return the character ‘F’ followed by a carriage return. If
the command executes successfully, the MMXI controller will return the first character of the
command sent followed by any returned values and finally a terminating carriage return
character.
All commands are case-sensitive.
The default format for numeric parameters and returns is decimal (base 10) variable length text
format. Integer parameters prefixed with ‘0x’ will be parsed as hexadecimal numbers. If a
command is prefixed with a lowercase letter ‘x’, the return values (if any) will be in hexadecimal
format. If a command is prefixed with a lowercase letter ‘b’, both the parameter values and return
values will use binary format. When using the binary ‘b’ prefix to a command, numbers are
received and sent in non-textual format byte for byte starting with the least significant byte. The
number of bytes transferred in binary format is always equal to the size of the value’s data type in
bytes (i.e. a 32 bit signed integer will use 4 bytes).
Command Set
The following pages describe the serial commands.
The notation below is used to indicate the type of data values used for parameters and
responses:
<CR> denotes a single carriage return character
<s16> denotes a signed 16-bit integer value
<s32> denotes a signed 32-bit integer value
<u16> denotes an unsigned 16-bit integer value
<u32> denotes an unsigned 32-bit integer value
