Owner's manual

HMP228
Operating Manual M210282en-A
16
3.2 Using the RS 232C serial bus
Rx GND Tx
Rx
GND
Tx
Nc
24V
Sensor connections
Current loop or
RS485 module
Ch1
Ch2
+
-
nc
Tx
GND
Rx
--
+
+
X17
X6
Figure 3.2.1 Serial bus connections
To connect a PC to the HMP228 transmitters via the RS 232C serial bus, one
of the following cables is required. The type of cable depends on the terminal
and the connector type.
2
5
3
3
7
2
3
7
2
TX
GND
RX
TX
GND
RX
TX
GND
RX
HMP228
D9S
D25S
D25P
PC
TXD
RXD
TXD
TXD
RXD
RXD
4
6
7
8
5
6
8
20
TERMINAL
Figure 3.2.2 Connection of cables
When the serial bus has been connected between the PC and the transmitter,
the PC is switched on. When using a PC, a terminal emulation programme
(e.g. Procomm Plus, Datastorm or Windows terminal) is started.
The factory settings for data transfer are:
• 4800 baud
• even parity
• 7 data bits
• 1 stop bit
• full duplex