User manual

User Manual
man_905K_1.10.doc Page 33
3.5.4 RS232 serial port
An RS232 port is provided for connection of a PC for configuration and diagnostics. To access
the serial port DB9 connector, remove the front cover from the module by unscrewing the four
screws in the front panel. The serial port is a 9 pin DB9 male and provides for connection to a
terminal or to a PC for configuration, field testing and for factory testing. Communication is via
standard RS-232 signals. The 905K is configured as DCE equipment with the pinout detailed below.
Pin
Name
Dirn
Function
1 - - Not Used.
2
RD
Out
Receive Data - Serial Data Output (High = 0, Low = 1)
3 TD In Transmit Data - Serial Data Input (High = 0, Low = 1)
4
DTR
In
Data Terminal Ready - used by 905K as a "wake-up" signal
5 SG - Signal Ground
6 - 9
-
-
Not Used.
The DTR signal must be connected to the 905K to enable communications and “wake up” the
microprocessor. This means that the DTR wire must be connected - the PC does not need to
control DTR. When communications is established, the green LED will light continuously.
The serial port communicates at a baud rate of 9600 baud, 8 bits, no parity, one stop bit.
An example cable drawing for connection to a personal computer is detailed below:
905K DB9 (M) Connector Computer DB9 (F) Connector
1
1
Not Used - optional
2
2
Receive Data
3
3
Transmit Data
4
4
DTR
5
5
Signal Ground
6
6
Not Used - optional
7
7
Not Used - optional
8
8
Not Used - optional
9
9
Not Used - optional