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6.4 INPUT AND OUTPUT QUEUE
The design of 64 bytes input queue and 128 bytes output queue for storing the pending
commands or return messages is to prevent the transmitted commands of remote control
and return messages from missing. As the maximum stored capacity for Error/Event
Queue is 20 groups of messages, it should be noted that input data exceeding the capacity
by using these buffers will cause data missing.
6.5 COMMANDS AND SYNTAX
6.5.1 RS232 message terminators
As there is no signal of end message on RS232 bus, therefore, use LF, CR, or CR/LF as
message terminator. After the 4176 processes a command a CR/LF is placed in the output
buffer and delivered. As for query command, the return message of the instrument is also
added a LF for PC to judge message terminator.
6.5.2 Entering Commands
The standards that govern the command set for the 4176 allow for a certain amount of
flexibility when you enter commands. The 4176 does not adhere to any friendly listening
standards so the commands and queries must be typed as specified.
6.5.3 Command Characters
The 4176s are not sensitive to the case of command characters. You can enter commands
in either uppercase or lowercase.
You can execute any command with preceding white space characters. You must use at
least one space between the parameter and the command header. Subsequent parameters
are separated by commas.
6.5.4 Combining Commands
You can use a semicolon (;) to combine commands, but not queries.
Example:
RANGE 4; HLCHI 14.999<LF>
