User Manual
Documentation No.3PXCC1x-2x-3903    35 
B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 
B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445 
Chapter 5: Communication Jumper Settings 
  This chapter will cover all of the jumper settings to set your B&B 
Serial Card for the proper communications that you desire. 
RS-232 Mode 
  To configure a port for RS-232 mode, 5 jumpers must be 
checked. The following settings will configure Port 1 as RS-232. 
1.  JP1A - must be set in the "232" (left) position. 
2.  JP1F - all four jumpers must be set in the "232" (left) position. 
  Jumpers JP1B - JP1E have no meaning in RS-232 mode 
and may be in either position. Figure 2 shows the jumper 
configuration to set both ports for RS-232 mode. 
Figure 2. RS-232 Mode Jumper Settings 
CAUTION: Electrostatic Sensitive Device. 
Use ESD precautions for safe handling. 
36 Documentation No.3PXCC1x-2x-3903 
B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 
B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445 
 RS-422 Mode 
  To configure a port for RS-422 mode, 7 jumpers must be 
checked. The following settings configure Port 1 as RS-422. 
1.  JP1A, JP1B, JP1C - must be set in the "422" (right) position. 
2.  JP1F - all four jumpers must be in the "422" (right) position. 
  Figure 3 shows the jumper configuration to set both ports for 
RS-422 mode. 
Figure 3. RS-422 Mode Jumper Settings 
  Note that the EIA RS-422 Specification labels data lines with 
an "A" and "B" designator. Some RS-422 equipment uses a "+" and 
"-" designator. In almost all cases, the "A" line is the equivalent of 
the "-" line and the "B" line is the equivalent of the "+" line. More 
information on RS-422 communications can be found in B&B 
Electronics’ free RS-422/RS-485 Application Note. 
RS-485 Mode 
  To configure a port for RS-485 mode, 9 jumpers must be 
checked. The following settings configure Port 1 as RS-485. 
1.  JP1A - must be set in the "422" (right) position. 
2.  JP1B, JP1C - must be set in the "485" (left) position. 
3. JP1D, JP1E - set to match software and installation 
requirements. 
4.  JP1F - all four jumpers must be in the "422" (right) position. 










