This command add a new member of the structure and only have sense inside BEGIN STRUCTURE .. END STRUCTURE commands.
Syntax:
MEMBER BINSTR <memberName> SIZE <nSize>
<memberName>
Name of the structure member.
<nSize>
Reserved size from the structure in bytes.
Description:
Store a binary string up to <nSize> characters and truncate the rest if longer or pad with \0 if shorter. Return a <nSize> characters string.