Wavetronix Click 500 (programmable controller) (CLK-500) - Developer Guide - Manual (Page 17)

16 CHAPTER 1 • USING THE CLICK 500
The right-side of this figure details the connections made to wire to a DCE DB-9 female
connector and then link to a computer via a straight-through serial cable. The TD and RD
labels on the serial cable are not referenced to the DCE device (Click 500) but rather to the
DTE device (PC). The arrows show the direction of flow; transmit data on the DTE device
becomes received data on the DCE device and vice-versa. This reversal of roles is why you
connect pin 2 of the DCE DB-9 female connector to the TD screw terminal and pin 3 to the
RD screw terminal.
NC NC TD RD
RS-232 Top Connector
DCE
DB9 Female
DTE
DB9 Male
(Computer)
1
2
3
4
5
GND
1
2
3
4
5
Serial Cable
RD
TD
To GND on
RS-485 Connector
2
3
Figure 1.4 – RS 232 Top
RS-485 Ports
The RS-485 serial ports are located on the T-bus connector, the RS-485 terminal block on
top of the module and the RJ-11 connector located on the front of the module. The RS-485
terminal on the top of the module and the RJ-11 jack on the front are electrically connected
and represent a single serial port. Figure 1.5 below shows the RS-485 pin-level descriptions
for this port. The other RS-485 serial port on the T-bus connector is physically independent
(see Figure 1.2).
-485 +485 GND GND
RS-485 Top Connector
RS-485 Front (RJ-11)
Connector
1
2 3
4
5
6
The RS-485 lines are shared
between these two connectors
GND
-485
+485
NC
Figure 1.5 – RS-485 Top/Front Connector