RST310 USER & INSTALLATION MANUAL
49
RS232 Specification
The RST-100 is provided with two RS232 serial ports for log and data connection.
Both are 9-pin D-type (female) sockets, wired DCE for connection to a standard PC
with a 1:1 cable.
Physical Connection
The pin-out of both connectors is described in the following table:
Pin
Signal
Direction
Description
1
DCD
RST PC
Data Carrier Detect
2 RXD RST PC
Received
Data
3 TXD PC RST
Transmitted
Data
4
DTR
PC RST
Date Terminal Ready
5 GND
Signal Ground (Common)
6
DSR
RST PC
Data Set Ready (CTS and DCD)
7
RTS
PC RST
Request to Send
8
CTS
PC RST
Clear to Send
9
RI
RST PC
Ring Indicate (7.5V on Log port)
RS232 Port Signal Support and Handshaking
On the data logging port, DCD and DSR output signals are related to DTR input and
CTS is tied to RTS as shown.
The Data port supports full software XON/XOFF handshaking on data (AT
commands bypass this as standard for Hayes modems) or full hardware
handshaking on RTS/CTS with DCD carrier indication.
The Log port has no software handshaking support and hardware handshaking is
loop-back only since the command set requires a minimal buffer.