Specifications
Documentation Number 232BSS4-0812m    15 
&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 – www.bb-elec.com 
B&B Electronics – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445 – www.bb-europe.com 
When the specified Port Time has elapsed, the 232BSS4 checks in 
sequence for other Slave ports with buffered data and switches to them. 
If no other Slave ports need access to the Master, the current Slave port 
will again be connected until another Port Time has elapsed. 
Inactivity Time: 
  The Inactivity Timer tracks how long a Slave port has been idle. The 
Inactivity Time is reset any time data is received on the connected Slave 
port or sent out the Master Port. This way, if the Master port is slower 
than the connected Slave port, the Slave port is not considered inactive 
while waiting for the Master to catch up. 
  Inactivity Time is set through the setup software. Times are set in 
milliseconds and can be anywhere in the range of 0 to 65,000 (65 
seconds). A value of zero for the Inactivity Time would give the 
transmitting Slave port access to the Master until a Port Timeout was 
reached or until a specific Turn Off command was sent from the Master 
device. 
Port and Inactivity Time Setup Tips: 
  Normally, the Inactivity Time should be set lower than the Port 
Time. Setting a zero for either value allows the other to have full control 
of port switching. Setting a value of zero for both timeouts keeps the 
Slave port connected until explicitly turned off by the Master device 
through the Turn Off all ports command. 
Slave Preamble: 
   Each Slave can be programmed to transmit a preamble to the 
Master device when the Slave becomes connected. This tells the Master 
device which new Slave is sending data. The preamble is set in the 
setup software and can be any character sequence up to four characters 
long. The preamble is sent to the Master device whenever a port is 
selected through commands or when the port will be sending data to the 
Master device because of an automatic switch. 










