SDM-SIO4 User Guide

NOTE

The hex. number must always be two ASCII characters.

 

 

Control characters can be entered for all commands in a similar way:

^M is carriage return, ^J line feed etc.

^^ means ^

"" means "

]] means ]

&& means &

&0d means line feed

&hex,hex used to enter 2-character hex. codes (0-9, A-F)

3.2 Input Filters

Input filters are used to convert received data into a form that is easy for the datalogger to process. Filters are generally used to strip out the required values from other, unnecessary, data transmitted from the sensor/device. The filters will also convert the required data into a form that the datalogger can use.

 

For example, the sensor may output the (unusual) complex string ‘Sample data

 

+12.3, 23.567,0xAB,12.4’. From this string you may only require to record the

 

hexadecimal number 0xAB. A filter can be set up to strip out only this number,

 

and then convert it to a 4-byte floating point number which the datalogger can

 

use. The datalogger will then collect this value and place it into an input location –

 

in this case as 171 decimal.

 

 

 

NOTE

You must always set up a filter if you want the datalogger to collect

 

data from the SDM-SIO4.

 

 

 

3.2.1 Filter Types

Simple Filters

These filters can be set up by the datalogger program, i.e. command line set-up is not necessary. The four filters search for a specific data type to convert to Campbell Scientific floating point format. The SDM-SIO4 continues searching and reading data until it encounters a termination character (if this has been specified in Instruction 113) The filters are as follows:-

Search for an ASCII floating point number to convert to Campbell Scientific floating point format.*

Search for an ASCII hex pair to convert to Campbell Scientific floating point format.*

Search for an 8-bit binary number to convert to Campbell Scientific floating point format.

Search for a 16-bit binary number to convert to Campbell Scientific floating point format.

* Non-numeric characters are ignored.

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Campbell Hausfeld SDM-SIO4 manual Input Filters, Filter Types, Simple Filters