HP E4418B Programming Manual page 393

SYSTem Subsystem
SYSTem:COMMunicate:SERial[:RECeive]:BITs <numeric_value>
Query Example
Error Message
If the word length is not in the range of values shown in the parameter
table, then the error message -224, "Illegal parameter value" will occur.
11-10
SYST:COMM:SER:REC:BIT?
This command queries the setting
of the receive/transmit word
length.
HP E4418B/E4419B Programming Guide