TAR-3 Resistance Meter Results File

SD Cards, Files and File System

This Application Note is written to accompany RM Frobisher (1986) Ltd's TAR-3 Resistance Meter Operator's Manual. It contains details of the TAR3DATA.TXT results file. The information contained in this note is for programmers who may want to write their own software to parse the data file. RM Frobisher (1986) Ltd have software (in C# and Perl), please contact us if you would like a copy or help.

The TAR-3 Meter stores the results of each grid on a removable "micro" SD Card in a file called TAR3DATA.TXT.


  • The measured output is in Ohms.
  • A plain text file.
  • Contains only ASCII characters.
  • Can contain up to 99 grids.
  • Results from each new grid are appended to the end of the file (the bottom).
  • Each Grid has a 'header' information.
  • The data is comma separated.
  • Each Grid is preceded by a blank line.
  • Each Grid has a trailing blank line.
  • There are two blank lines between grids!
  • 'DUMMY' reading are marked with ', Dummy' (comma – space – Dummy).
  • The Data file may contain any number of grids – some of them may not be required/used.
  • Grid numbers can be edited by the user and may not be unique!

Note: If a DUMMY reading as been created in a block, the resistance will be set to 100.0000. If an individual reading has been marked as a DUMMY, the reading will be unchanged. The actual reading will have been marked as a DUMMY. Programmers should ensure that their software can deal with any DUMMY value.

'1,1.0,1.0,100.0000, Dummy' or '1,1.0,1.0,92.1234, Dummy' – are valid examples of DUMMY readings

The TAR-3 Resistance Meter uses 32bit floating point numbers and 32 bit integers as standard. There are no 'Magic or Flag' numbers like 2048 (11 bit), or 65536 (16 bit)

TAR-3 Data File (ASCII text)
TAR-3 Data File (ASCII text)