Casella CEL Nomad portable weather station - Manual (Page 54)

It is to this port that a PC is usually connected in order to
program/interrogate the logger. The Sensus Logger is shipped from Casella CEL
with this primary command interface set to the following parameters:
Default parameters - Primary command interface
Baud rate
9600
Data bits 8
Parity None
Stop bits 1
Handshake None
All of these parameters may be changed using commands built into the logger
software interface.
The same command channel is also accessible from the connector
array. This time the interface signals appear on a 5-way spring terminal block.
This is of use where power and communication are supplied via a fixed
cable. The communications signals can be connected to a 9-way D-type
connector without the need to prepare the ends of the cable.
The pin connections for the RS 232 Command - Spring terminal
connector are as follows.
Pin Assignment
1 Ground
2 Transmit data (out)
3 Receive data (out)
4 DTR (out) (linked internally to 7)
5 CTS (in)
7.5.2 Sleep Mode
When enabled, the logger will conserve power by switching off the RS 232
interface circuitry after a period of inactivity. While in this state the logger is still
able to detect the arrival of characters over the command interface and when
the first character arrives, the logger will waken and switch on the RS 232
interface again.
However this can mean that the logger may not interpret the
first character correctly.
7.5.3 Display
The Sensus Logger supports a 2-line by 20-character LCD module, 4 keys and a
buzzer. The LCD incorporates a back light that is lit for a few seconds on every
key press.
The display provides information about the internal status of several of
the key functions of the logger, these include date/time, active channels and
logging summary.
The LCD will always show something, unless the logging period has
been set to one minute or more, whereupon an internal power-save function
comes into effect and the LCD becomes blank, switching on again only as data is
logged.
Should the LCD be blank, it can be reactivated immediately (without
having to wait for a log cycle) by pressing any one of the front panel keys.
7.6 CompactFlash™ Cards
CompactFlash memory cards are lightweight, small form factor, removable data
storage devices built around reliable Flash storage technology.
The Sensus Logger’s integrated CompactFlash slot allows it’s storage
capacity to be increased and in addition provides a compact and reliable method
of transporting data from site for analysis. The slot is located on the right-hand
Sensus Data Logger
Page 54 of 68
NOMAD Portable Weather Station
Users Handbook