Advantech PCI Series User Manual page 25

Table 2.2: Board ID Setting
11 OFF
12 OFF
13 OFF
14 OFF
15 OFF
Note: On: 0, Off: 1
2.3.3.3 Tx Enable Mode Selection (SW2)
Tx Enable Mode is set by two, four, or eight position DIP switches (one for each port).
If a switch is set to "On," the driver of the corresponding port will always be enabled,
and the COM port will change to RS-422 master mode, which means that the Tx out-
put is always enabled. If a switch is set to "OFF," the driver will be in Auto Direction
Control Mode. You must select a mode before beginning any RS-422 applications.
(PCI-1620A/PCI-1620B/PCI-1622B are SW1)
Table 2.3: Tx Enable Mode Selection
Mode
RS-422_Master
RS-422_Slave/RS-485
Note! Do not set termination resistors in RS232 mode.
ON
OFF
OFF
OFF
OFF
Switch Position Description
ON Tx always enabled
OFF Auto direction control enabled
15
OFF OFF
ON ON
ON OFF
OFF ON
OFF OFF
PCI Communication User Manual