Table of Contents
Advertisement
Appendix E
E-4.1
General Operation of the ADFM Analog Output Module
Once programmed, the ADFM Analog Output Module follows a defined
sequence of operation. Most simply expressed, it will:
a. Wait for data from its associated ADFM
b. Parse the incoming data stream to obtain the depth, velocity, and
flow rate
c. Update each analog output channel based on the incoming data and
the desired scaling
d. Update the local LCD display with the current data
Several error-handling procedures are incorporated into the standard pro-
gramming. Foremost among them are the actions to be taken if either a) no
data, or b) bad/missing data, is received from the ADFM. While waiting for
data from the ADFM, the first line of the LCD display will show the word
"Waiting" followed by a series of three numbers. The first of these num-
bers is the number of consecutive bad or missing flow rate readings from
the ADFM. The second is the number of consecutive bad or missing depth
readings from the ADFM. The third is a count of how long, in 20-second
increments, it has been since data was received from the ADFM. If data is
not received from the ADFM within the specified time window, it is treated
as having received bad or missing data. When the number of consecutive
bad or missing readings reaches or exceeds a specified threshold, the out-
put(s) are set to a user-specified level for warning and diagnostic purposes.
NOTE. Customized programming can be used to change the error
handling procedures and/or the data shown on the local display. Please
consult any system-specific documentation or contact MGD Technologies
Inc. for further information if you suspect your system may not conform to
the standard display and error-handling characteristics described above.
E-4.2
User Input Parameters
User Input Parameters to the ADFM Analog Output Module's BASIC code
are grouped at the beginning of the program file. Typical inputs include
zero scale and full scale values for each analog output channel, the number
of consecutive bad or missing input values to allow before reporting an er-
ror condition, the values to be output as signals of an error condition, the
amount of time to wait between successive input values, and the amount of
smoothing to be applied to the incoming data. Minor changes in these pa-
rameters can easily be made by most users, however, changes in user units
and large scaling factors may affect other portions of the program. Please
contact MGD Technologies Inc. for assistance if you have questions about
changing the user input parameters.
page E-10
MGD Technologies, Inc.
Advertisement
Table of Contents
