ISCO 4230 - 4.2 Connections to External Serial Device

4230 Flow Meter
Section 4 Optional Equipment
4-4
You may find the following booklet, prepared by the FCC,
helpful: How to Identify and Resolve Radio-TV Interference
Problems. This book is available from the U.S. Government
Printing Office, Washington, D.C. 20402, Stock No.
004-00-00345-4.
4.2 Connections to
External Serial Device
Isco offers two serial outputs from 4200 series flow meters. There
is a software-enabled output that is transmitted on the RAIN
GAUGE connector. This signal also appears on the INTERRO-
GATOR connector. This feature lets the flow meter transmit the
most recent values for all currently enabled ports as ASCII text.
You can select the baud rate and the frequency of transmission.
You can then write a simple program to retrieve this data period-
ically, or you can do it interactively using a terminal program.
This option (SERIAL OUTPUT) is discussed in detail in Section
2.7.2.
Isco still offers the older 300 baud output for the Model 2312
Plotter (no longer sold) also on the RAIN GAUGE connector. This
port provides ASCII level and flow rate data for remote trans-
mission to any ASCII-compatible equipment. Every 15 seconds
the flow meter transmits a line of data which includes level,
units of level measurement, percentage of maximum flow rate,
maximum flow rate, a total flow value, units of flow, sample
number, bottle number, text, time, and date.
If you are using the flow meter with an Isco sampler, the data
line also includes an indication of a sampling event.
You can transmit this data line to a computer, or to a locally-con-
nected (within 250 feet) device capable of interpreting serial
data, such as a video display terminal or a printer. The specifica-
tions for this serial data output are as follows: 300 baud, 7 data
bits, 2 stop bits, even parity. The printed (or displayed) line con-
tains 110 characters and will appear similar to the following:
+01.409F 100.00% 2.500+0 CFS 0001533+0 CF 00 00 90
DEGREE V-NOTCH WEIR
000 0 90 04 04 02 31 48
The last two characters (not displayed) are a `CR' (carriage
return) and a ‘LF' (line feed). The large gaps between some of the
words indicate extra character spaces which are not used in this
particular text, but which are available for use if needed.
Note
1. You cannot use both serial outputs at the same time. You
must select one or the other.
2. The serial output is paralleled with the Interrogator Port and
the Internal Modem. Use of either the Interrogator Port or the
Internal Modem will cause non-standard data to be transmit-
ted.