2 ec100configure() instruction, Ec100configure() instruction – Campbell Scientific EC155 CO2 and H2O Closed-Path Gas Analyzer and EC100 Electronics with Optional CSAT3A 3D Sonic Anemometer User Manual

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EC155 CO

and H

O Closed-Path Gas Analyzer

10.2 EC100Configure() Instruction

This instruction is another way, besides ECMon and Device Configuration, to

retrieve and modify settings. ECmon and Device Configuration are user-

interactive, while the

EC100Configure() instruction allows automated control

under CRBasic datalogger programming.

EC100Configure() is a processing instruction. Whether running in pipeline

mode or sequential mode the datalogger will execute the instruction from

processing. This functionality allows the instruction to be placed in conditional

statements. Running from processing also introduces ramifications when

attempting to execute the

EC100Configure() instruction while other SDM

instructions are executing in pipeline mode. This instruction locks the SDM

port during the duration of its execution. If the pipelined SDM task sequencer

needs to run while the SDM is locked, it will be held off until the instruction

completes. This locking will likely result in skipped scans when reconfiguring

an EC155.

For the EC155 to save settings, it must go through a lengthy write-read-verify

process. To avoid saving the settings after each set command, the result code

can be used to determine if any settings were modified from their original

value. When a change is detected the save settings command (command code

99) can then be sent to the EC155. The DestSource parameter variable should

be set to 2718 to save the settings. The reception of this command is

acknowledged but since it takes up to a second to complete, a successful return

code does not mean that all of the data was successfully written to the

appropriate non-volatile memory.

The instruction syntax is:

EC100Configure(Result,SDMAddress,ConfigCmd,DestSource)

Result is a variable that contains a value indicating the success or failure of the

command. A result code of 0 means that the command was successfully

executed. If reading a setting, 0 in the result code means that the value in the

DestSource variable is the value the desired setting has in the EC155. When

writing a setting, if the result code is 0, the value and setting were compatible,

but the value was not changed because it contained the same value that was

sent. A return code of 1 from the set operation means that the value was valid,

different, set and acknowledged. This allows CRBasic code to control whether

or not to save the settings. NAN (i.e., not a number) indicates that the setting

was not changed or acknowledged or a signature failure occurred.

SDMAddress defines the address of the EC155 to configure. Valid SDM

addresses are 0 through 14. Address 15 is reserved for the

SDMTrigger()

instruction.

ConfigCmd is a variable that indicates whether to get or set a setting. The

options are listed in TABLE 10-4.

DestSource

is a variable that will contain the value to read when getting a

setting, or that will contain the value to send when writing a setting to the

EC155.