You know what sucks? Not being able to connect to CareLink from your nifty, modern Mac because Lifescan and/or Minimed decided it wasn’t worth creating a new driver for the cable that connects a OneTouch blood glucose meter to your USB port. Now, it is cool that they gave me a free Bayer USB Contour meter, but I haven’t switched over my prescriptions yet. So, yeah.
You know what else sucks? Needing to use CareLink at all, when what I really want to do is to communicate with my meter from MATLAB directly. I did this in the past with a Freestyle meter, and that showed me how much better the world can be if programmers have direct access to the medical device data. Not everybody’s thing, of course, but what one of my college professors told another guy in the lab when I was inexplicably trying to configure the “broken” HP machine to run X-Windows still holds true: “Some people are high-level people. Some people are low-level people. Jeff is a low-level person.”
Well, I’d finally had it with the “You can’t upload to CareLink or download into MATLAB” bullshit, so I decided to try to fix this problem with a few pointers from the Test and Measurement team (a.k.a., the Data Acquisition Toolbox and Instrument Control Toolbox folks) at the office. I’m a hardware newbie so I prepared to learn a lot. Fortunately, there wasn’t a lot to learn. Mostly just the role of the hardware driver.
I’m happy to report that it is completely possible to connect a OneTouch meter to CareLink using the USB-to-serial meter that you can buy from Lifescan. It does require obtaining and installing a driver on your system, but that’s pretty straightforward. You only need the nerve to open a terminal window on your Mac and use the sudo command. Sounds scary, but it’s not. (Still, it was enough to prompt me to do the weekly computer backup before starting. I needed to do it anyway.) Pretty easy stuff. Here we go.
For the record, there’s a third-party vendor that makes a USB-to-serial cable for OneTouch meters that ships with a CD that should take care of all of this for you. I haven’t used it, but they pointed me to the right drivers that they thought might work with the cable I already had. I thought was a pretty stand-up thing to do. (BTW, they and Lifescan use different chipsets in their cables–Prolific PL2303 chip for Lifescan vs. FTDI for Celeritous. The important thing to note: Different chips in the cables require different drivers.)
Okay, how to get the Lifescan USB-to-serial cable working with MacOS 10.8 . . . and maybe 10.6 and 10.7.
- Download the PL2303 driver from Prolific. I needed to get the file md_PL2303_MacOSX-10.6up_v1.5.0.zip, which was the latest version at the time.
- Remove any previously installed ProlificUsbSerial.kext drivers. Why is it there when it won’t work? I don’t know. I do know that mine was from 2006, which was probably from my previous MacBook. The instructions tell which “sudo” command to use. This is the trickiest part, and it’s pretty easy. (For the record, I moved mine with the following command just in case things went south:
sudo mv /System/Library/Extensions/ProlificUsbSerial.kext ~/tmp/
You will need to know the administrator password, which is probably the same as your login password.
- Right click to “Open” and run the installer package.
- Reboot. Why? Because installing drivers requires a reboot.
- Go to CareLink and enjoy uploading all of your data again.
As for me, I’m going to get reading that Lifescan document. You know, the super-secret one that talks about how low-level people like me can interface with the OneTouch meters via serial port. More on how that’s going another day.