- I am making a program in Linux PC to extract realtime data from datalogger CR200X.
As my investigation, realtime data is stored in 'Public' table. But there are some points, I am not clear.
1. What is the procedure to get data from a table (Public table)?
2. What is the structure of Public table (number of records, fields, etc)?
Could you give me some suggestions?
Thanks!
The public table is composed of variables declared as 'public' in the program running in the datalogger. Other tables may defined in the program, typically logging data values under program control. The logger has a simple terminal interface using the rs232 serial port; commands are single characters which you can enter when a prompt is issued, probably 'CR200>'. Hit enter several times to get the prompt, then hit a key within a few seconds. Commands include: '7' to see the public variables, 'J' to see a listing of the program, and 'h' to get a list of commands.
Campbell Scientific has programs to interface with their dataloggers, but most are for Windows. Their LoggerNet Server for Linux is useful, though Windows is required for a GUI interface and to read detailed documentation (which is only available as Windows Help files). It is possible to use the LoggerNet Server's Cora-Script interface directly via linux, however, which exposes complete functionality of the server.
You can probably get details on the PakBus protocol from Campbell Scientific if you want to code to it directly, and some third-party interface libraries are available.
Thanks for your answer:
The public table is composed of variables declared as 'public' in the program running in the datalogger. Other tables may defined in the program, typically logging data values under program control. The logger has a simple terminal interface using the rs232 serial port; commands are single characters which you can enter when a prompt is issued, probably 'CR200>'. Hit enter several times to get the prompt, then hit a key within a few seconds. Commands include: '7' to see the public variables, 'J' to see a listing of the program, and 'h' to get a list of commands.
I am waiting for device CR200X so that I could not try the command now.
I do not add new table definition in Data Logger, I want to use the default table.
So could I get real time data of sensor from 'Public' table?
You can probably get details on the PakBus protocol from Campbell Scientific if you want to code to it directly, and some third-party interface libraries are available.
I am using the interface library PbCdlComm but I am not clear in extracting data from 'Public' table.
I'm not sure I understand your situation, but a program is needed in the logger in order for it to do anything. You could wire sensors to it, but nothing will happen unless a program is running. There is a default table or two, e.g., the status table shows various settings defined in the logger operating system, but a program needs to be running in order to see any sensor data.
It is possible to query the public table (assuming public variables are defined), and those values are 'real time' in that they show the value at the time of the query, but the value is set by the running program, so it could be new or old depending on the program.
Thanks for your support!
It seems that there is no default table and program on Data Logger.
I must create a program on Data Logger to extract data from sensor.
When discussing retrieval of data from a CR200X without using CSI software, don't forget to check out section 8 of the manual "settings via terminal emulator". Using a terminal and starting with option 6, you can retrieve the latest data table record or loop back through historical data.
* Last updated by: Sam on 1/31/2012 @ 7:04 PM *
Wow... That's very interesting. I've only seen logged table data by using command '8', but it's awkward and confusing. I'll have to check out command '6'. Thanks for pointing this out. I do use LoggerNet-Linux, but would like alternative ways to get at data, e.g., perhaps in the field using a laptop or Android device.
To Sam:
Thanks for your feedback.
On the interface of PC200W software, It seems that the 'Monitor Data' tab displays the realtime data.
Which table does it get from Data Logger?
Thanks!
* Last updated by: khanhlv1407 on 2/1/2012 @ 2:52 AM *
Monitor Data allows you to select fields from any of the tables and have them updated at the "Update Interval". These values can be from your Public and Status tables or from a DataTable that you have declared in your program.
When discussing retrieval of data from a CR200X without using CSI software, don't forget to check out section 8 of the manual "settings via terminal emulator". Using a terminal and starting with option 6, you can retrieve the latest data table record or loop back through historical data.
Thanks for your sharing!
1. In section 8.3.3 Settings via Terminal Emulator, It described the command " option 5 for Public table (real time values)"
--> I want to confirm:
1. 'Public' table is default table or it is created by user?
2. If it is default table, could I get the data of Public table without creating program on CR200X?
3. If it is default table, How to know the structure of Public table?
Thanks!
* Last updated by: khanhlv1407 on 2/7/2012 @ 7:42 PM *
The dataloggers do not measure anything without programming.
* Last updated by: Sam on 2/7/2012 @ 7:54 PM *