LPL Topics
Analog Measurements
23-66
Using the LI-6400
23
Analog Measurements
Analog measurements are meaningful only on platforms that have the hard-
ware capability (an A/D convertor) to accomplish this task. However, all plat-
forms support the LPL keywords, and may provide an interface for getting
measurements from another device. At any rate, LPL provides a lot of flexi-
bility in its analog measurement capability.
Groups and Channels
At the heart of LPLÕs treatment of analog measurements are two concepts:
group
and
channel
.
A channel is a physical measurement channel, and corresponds at some point
to where a wire must be connected. Each channel has an address, starting with
0, and the number of channels available is one of the three values obtained via
. Thus, if there are 24 channels, they are addressed as 0 thru 23.
A group, on the other hand, has no physical manifestation. A group is simply
Table 23-27.
Analog Measurement Keyword Summary
Keyword
Description
Returns the number of analog input channels, ground chan-
nels, and maximum number of groups that can be defined.
Create an internal A/D structure.
Dispose of an A/D structure.
Define a group.
Define a channel in a group.
Build the action table based on the defined groups and
channels.
Start or resume the A/D.
Stop the A/D.
Are readings available?
Get a reading
Get a reading with the time stamp
Dispose of the action table.
Summary of Contents for LI-6400
Page 1: ...Using the LI 6400 Portable Photosynthesis System ...
Page 15: ...Part I The Basics ...
Page 16: ......
Page 174: ...Making Measurements Answers to Questions 4 56 Using the LI 6400 4 ...
Page 175: ...Part II Useful Details ...
Page 176: ......
Page 200: ...Standard Tools Power ON Hooks 5 24 Using the LI 6400 5 ...
Page 214: ...Real Time Data Real Time Graphics 6 14 Using the LI 6400 6 ...
Page 234: ...Environmental Control Light Control 7 20 Using the LI 6400 7 ...
Page 244: ...Light Sensor Considerations Gallium Arsenide Phosphide GaAsP Sensor 8 10 Using the LI 6400 8 ...
Page 288: ...Data Logging Making Your Own AutoPrograms 9 44 Using the LI 6400 9 ...
Page 289: ...Part III Working With Files ...
Page 290: ......
Page 312: ...The LPL File System Troubleshooting 10 22 Using the LI 6400 10 ...
Page 340: ...Downloading Files Using a Data Capture Program 11 28 Using the LI 6400 11 ...
Page 375: ...Part IV Configuration Issues ...
Page 376: ......
Page 420: ...Defining User Variables Old Style vs New Style 15 18 Using the LI 6400 15 ...
Page 454: ...Using an Energy Balance Further Reading 17 12 Using the LI 6400 17 ...
Page 455: ...Part V Maintenance Troubleshooting ...
Page 456: ......
Page 572: ...Troubleshooting Useful Information 20 46 Using the LI 6400 20 ...
Page 593: ...Part VI Programming ...
Page 594: ......
Page 622: ...Programming with LPL Compiler Directives 22 28 Using the LI 6400 22 ...
Page 846: ...Index I 16 Using the LI 6400 ...