B&B Electronics RS-422 manual Selection of Operating Mode, Set the Jumpers, Jumper/Mode Table

Selection of Operating Mode

The hardware address and IRQ is set by the Windows Operating System using driver information files and the Plug and Play OS.

The Operating Mode is set using Jumpers, Device Manager Driver Settings and by your cable connections and software.

Set the Jumpers

Set the 3 JP1 Jumpers to match your Operating Mode.

Table 1 – Jumper/Mode Table

The top jumper sets DB9 connections for either 232 or 422/485

RS-232 operation requires setting only the Top jumper.

The middle jumper sets the RS-422/RS-485 transmitter for RS-485 or RS-422 operation. In RS-485 mode, the transmitter is tri-stated when not sending data.In RS-422 mode, the transmitter is always enabled.

The bottom jumper sets the RS-422/RS-485 receiver for half-duplex RS-485 operation or full-duplex RS-422/RS-485 operation. In Half Duplex RS-485, the Receiver is Enabled when not transmitting. In Full Duplex RS-422/485 operation, the receiver is always enabled.

For more operating mode information, see the related chapter.

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