SD Cards, Files and File System
The TAR-3 Meter stores the results of each grid on a removable "micro" SD Card in a file called TAR3DATA.TXT.
The TAR3DATA.TXT file
- 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)