Serial Interface (Com1/Com2); Rs-232 Interface (Com1); Rs-422/485 (Com2) Detection; Automatic Data Flow Control Function For Rs-485 - Advantech UNO-3483G Series User Manual

2.2

Serial Interface (COM1/COM2)

The UNO-3483G offers one standard RS-232 and one RS-422/485 serial communi-
cation interface ports: COM1 and COM2 (Pin header CN31).
The IRQ and I/O address of serial ports are listed as below.
COM1: 3F8, IRQ4
COM2: 2F8, IRQ3
CN31
2.2.1

RS-232 Interface (COM1)

UNO-3483G offers one RS-232 serial communication interface ports: COM1. Refer
to Appendix A for their pin assignments.
2.2.2

RS-422/485 (COM2) detection

In RS-422/485 mode, UNO-3483G automatically detects signals to match RS-422 or
RS-485 networks. (No jumper change required).
2.2.3

Automatic Data Flow Control Function for RS-485

In RS-485 mode, the UNO-3483G automatically detects the direction of incoming
data and switches its transmission direction accordingly. So no handshaking signal
(e.g. RTS signal) is necessary. This lets you conveniently build an RS-485 network
with just two wires. More importantly, application software previously written for half
duplex RS-232 environments can be maintained without modification.
Figure 2.3 Pin header of COM1/COM2
9 UNO-3483G User Manual