RS-485 interface
The RS-485 interface supports 2-wire connection. The dip switch S1 is used to switch the termination and signal biasing resistors on or off.
Termination
Interface type
Figure 1. Dipswitch positions of VSE 002
The direction control of the RS-485 transceiver is done with the RTS signal or automatically. The automatic direction control turns the transceiver to transmit mode after detecting the falling edge of a 0-bit. The direction is kept in transmit mode for 0,5ms. This enables the use of the automatic mode with 9,6 kb/s and 19.2 kb/s speeds. When the transceiver is changed to receive mode, the RS-485 line changes state to logic 1 state due to the biasing resistors.
VVSE2/EN M/B006
