Description of the signal inputs and outputs
34
Serial interface
The serial RS232 interface transfers measurement data and alarms
or notifications in plain text or ASCII in CSV format. It is always ac-
tive. The baud rate is set to 9600.
Transmission is in the 8 bit format, 2 stop bits, no parity.
A new measurement value is transmitted as soon as it has been de-
termined. New alarms are transmitted via the serial interface and
some alarms even when the alarm has been ended (see
on page 35).
Notification format
The messages are stored in “Comma Separated Value” format:
•
Field separator is a comma.
•
Decimal separator is a full stop.
•
Each data set is
started with the ASCII characters “02”
<STX> and terminated with “03” <ETX>.
•
Notifications and measured values can be distinguished by
evaluating the first characters: If “ME” is read, it is a meas-
ured v
alue; with “AL”, it is an alarm or notification.
•
This corresponds to the format of the Testomat 2000
®
data
logger.
Even though the device does not have a limit value function,
the same fields are transferred for compatibility reasons.
Example of measured value:
<STX>ME,TH2005,31.07.2013,08:09,0.050,°dH,limit
val.1:,0.200,°dH,limit val.2:,0.300,°dH<ETX>
Examples of notifications:
<STX>AL,turbidity,01.08.2013,07:30<ETX>
<STX>AL,turbidity inactive,01.08.2013,07:35<ETX>