B&B Electronics 232XS5 User Manual

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232XS53800 
Manual 
B&B Electronics  --  PO Box 1040  --  Ottawa, IL  61350 
PH (815) 433-5100  --  FAX (815) 433-5109
 
10
 
 
NOTE:  When a port is selected via the Master Port, the RTS 
lines will be ignored until the Master Port sends the turn off code. 
When the Master Port is selected by RTS, all preamble codes 
will be ignored.  The port combiner function is not available with 
the Master Port configured as a DCE or in expansion mode. 
 
 
A typical application would be to have RTS and CTS tied together 
on the master port.  When RTS on port A is asserted, CTS on port A 
will be asserted when a connection is established.  If a port is not 
connected to the master port, then CTS on that port will remain low.  
Therefore, a port can monitor the handshake line to determine if a 
connection has been established. 
Enhanced Timer Mode -- Timer Features  
 
The 232XS5 has an enhanced mode, which offers special timer 
features.  The timer features can be used to prevent slave devices 
from receiving preamble commands, inadvertent switching from 
binary/graphic file transfers, and inactive slave devices from holding 
control of the master port.  The timer has two different modes:  an 
inactivity mode and an inadvertent switch mode.  When in inactivity 
mode, the 232XS5 will monitor the data lines.  If there is no activity 
for the specified time, the selected slave port will be disconnected 
from the master port.  When in inadvertent switch mode, the 
232XS5 will ignore switching commands for the specified period of 
time.  After this time has expired, the selected slave port will be 
disconnected from the master port. 
 
The timer functions are enabled via a jumper setting and 
through software commands.  Jumper JP6-A must be OFF 
(removed) for the 232XS5 to be in enhanced mode.
  The 
software commands follow the same format as preamble codes 
used for switching.  There are two commands that must be sent to 
the 232XS5 to set the timer functions:  Set Timer Value and Set 
Timer Mode.  These commands require an additional byte for data.  
The Set Timer Value command requires the third byte to be an 
ASCII “T” character.  The data byte (fourth byte) must be a value 
between ASCII “0” and ASCII “9”.  A value of “0” is used to disable 
the timer.  The time set by the Set Timer Value command 
determines the length of time the 232XS5 wll wait before 
disconnecting an inactive port, or the length of time it will ignore 
switching commands from the master.  Refer to Table 7 for timer 
values.  For example, sending the following string to the 232XS5 will 
set the timer value to 5 seconds (assuming programmable character 
is the factory default of 2).