Instruction Manual

Board Interfaces 43

cPCI-3970

COM1 Mode Selection Switches (SW1~SW4)

These switches set the cPCI-3970D/P COM1 to RS-232 full

modem, RS-422, RS-485, or RS-485+ half-duplex mode.

Switches SW1~SW4 are located on the top edge of the

DB-3610L2 board. RS-232 full modem is set by default.

Table 4-8: cPCI-3970D/P COM1 Mode Selection Switch Settings

Mode Pin SW1 SW2 SW3 SW4

RS-232

1ON ON ONOFF

2OFFOFFOFFOFF

3 OFF ON ON OFF

4OFFOFFOFFOFF

RS-422

1 OFF OFF OFF ON

2ON ON ONOFF

3 OFF OFF OFF ON

4 OFF ON ON OFF

RS-485

1 OFF OFF OFF ON

2 OFF ON ON OFF

3ONOFFOFFON

4 OFF ON ON OFF

RS-485+

1OFFOFFOFFOFF

2 OFF ON ON ON

3ONOFFOFFOFF

4 OFF ON ON ON

NOTE:

The COM mode setting for cPCI-3970D/P models must be set

using the SW1~SW4 DIP switches above. The cPCI-3970G

COM1/2 Output BIOS setting is only used for cPCI-3970G/U

models.

SW1 SW2 SW3 SW4