Thursday, January 1, 2015

Freestyle Libre RAW data (TI update)

More info from TI now officially available

Very quick update

It turns out that most of what I found out and explained in my Dec 4 and Nov 27 posts about the Libre RAW data format, plus some of the information I shared in private with some of the readers who contacted me directly, is mostly about how the RF430FRL152H or - more precisely - the RF430TAL152H Abbott uses operates. I had decided to take a small analysis vacation and, sure enough, Texas Instruments decided to release a ton of documentation as soon as I stopped looking.

The information is now available here:

That line of products is actually quite interesting as an enabler for different kinds of bio-sensors.

Having access to that in November would have saved me a couple of evenings and an arm cramp. On one hand, I am a bit sad to have lost time but, on the other hand, I am quite happy to see my assumptions, including the ones about the DAC confirmed. However, some of the things I have confirmed on my three sensors are strikingly similar but slightly different from what the TI manual describes. It could be that the TAL is either a custom variation of the FRL developed specifically for Abbott (is this what the A stands for? Not necessarily as TI typically has a technology based naming convention) or a product that is in the pipeline for everyone but to which Abbott got early access. Time will tell I guess.

As a side note, our third sensor suddenly stopped working (in interesting circumstances...) after ten days and was flagged as having failed by the reader. This led to interesting insights about error modes, and how the flags changed in the device FRAM.

A bit of data analysis should, at some point, tell us if the "magic" of the Libre sensor is due to the quality of its signal or sophisticated algorithms.


  1. Hello, I am a T1D for 20 years now and from bit of time (2 years) I have a number of hassle with my glucose.

    To let it get short, from this summer I wear the Libre and it is really convenient and free in Italy. I want to develop a little device that allows me to read glucose during the night and automatically send it to an app via BLE to perform the necessary action (alarm, etc.)

    So far so simple. Now comes the fun part, did you find other information to convert from raw to glucose?

    Thanks a lot.

  2. I forgot to check "notify me" :-)

  3. I answered myself. I read everything on your blog and on Limitter and BlueReader site.