Linux C++-17 code to download samples from a "ROCHE ACCU-CHEK Guide" blood glucose monitor using libusb

• install libusb-1.0-dev

• install build-essential

• in a shell, type:

  make

• connect your device via USB to your computer

• in a root shell, type:

  ./accuchek > samples.json

• blood glucose levels should be in file samples.json

• if it didn't work see "a number of things can go wrong" below

• scans all USB devices in the system
• finds an Accu-Chek Guide device if there's one
• connects to it
• downloads all blood glucose samples
• dumps them as JSON on stdout
• hopefully exit gracefully

• This has been tested on Ubuntu 20.04. On other Unixes, YMMV.

• The file config.txt contains the USB id's of supported devices. If you have a slightly difference device that may work with this code, add its parameters (found in the output of lsusb) to the file and see if it works. Please submit a PR of it does.

• This is a rough first cut, improvements via PRs are welcome.

• Unless you enjoy futzing around with udev and the like, you should run the utility as root

• Produced JSON has glucose levels in both mg/dL and mmol/L units

• The ascii timestamps in JSON are expressed in the local device time

• The epoch timestamps in JSON are GMT, assuming the computer running the utility is set to the same timezone as the Accu-Chek device.

• The proprietary USB protocol needed to talk to the device was reverse-engineered from the Javascript code found here the author of which likely had access to the vendor documentation:

  https://github.com/tidepool-org/uploader/tree/master/lib/drivers/roche

• The JS code has a little more functionality (eg it can set the device time), but as much as I can ascertain, it's not particularly portable: it only runs on top of Chrome, and even there, I have never really managed to get it to run on anything but windoze: the amount of dependencies you have to install to ever hope to see it run is simply frightening.

• A number of things might go wrong with this code. When that happens:

  • disconnect device USB cable
  • kill the utility
  • re-connect device USB cable
  • make sure it says "data transfer / transferring data" on the device screen
  • type in a root shell: export ACCUCHEK_DBG=1
  • from the same shell, run the utility again to see what the problem is