HP 24SII - Manual (Page 77)

NOTE: A serial computer connected to a port other than Port 1 of
Module 1 cannot access configuration mode for its module while the
master configuration port is configuring a module.
NOTE: If a computer attempts to configure a feature that is only
accessible to the master configuration port, Port 1 of Module 1, the
computer will be sent this message by the Model 24SII DES:
This Option is accessible via Port 1, Module 1 ONLY.
Strike any Key to continue
NOTE: If a computer port other than the master configuration port
attempts to access configuration mode of a module that it is not
connected to, the Model 24SII DES will ignore the configuration
request and create a print job consisting of
Control-T , C, and the
module number.
CAUTION: If you have a M24SII-V07 installed as Module 1, do not
configure Port 1 of this module for any baud rate higher than 115,200
or you will locked out of configuration mode and unable to program
the various features of the Model 24SII.