[ubuntu-uk] Reverse engineering data files

[Paul Sladen]

On Thu, 27 Nov 2014, Gareth France wrote:
> The file we began looking at came from my old machine
> ... the basic structure remains the same.
> 01 looks like

0x01 is probably the number of samples that follow for that
particular test type (F3 "Earth Insulation") in this case.

> other one/two are the result.

The top bit 0x8000 is the fail/pass flag.

  0x90b7 >> 15 => 0x0001 => FAIL
  0x4879 >> 15 => 0x0000 => PASS

> But these converted to either text or decimal bare no resemblance

The remaining fifteen lower bits converted to decimal match exactly:

> >> F3 01 90 B7  - 42.79 - 0x90b7 & 0x7fff => 0x10b7 => 4279 decimal
> >> F3 01 97 78  - 60.08 - 0x9778 & 0x7fff => 0x1778 => 6008 decimal

	-Paul