It’s usually the small stuff that breaks

By Greg Turnquist

Greg L. Turnquist worked on the Spring team for over thirteen years and is a senior staff technical content engineer at Cockroach Labs. He was the lead for Spring Data JPA and Spring Web Services. He wrote Packt's best-selling title, Learning Spring Boot 2.0 2nd Edition, and its 3rd Edition follow-up along many others.

July 12, 2011

I just fixed a nasty problem: my iPhone wouldn’t stay linked to my MacBook Pro through the USB connection. This has huge repercussions.

Using MyWI, I have been able to work for the past five weeks at a friend’s house despite the lack of broadband internet. At first, I used the USB mode, where it tunnels through the USB to send packets and forth to my iPhone, which in turn links to the internet. But after a bit, this stopped working. I noticed that it didn’t maintain the connection. iTunes stopped showing the iPhone as well.

I started tracking things down. I typed “sudo dmesg”, and looked at the logs. It seemed like it was having a hard time seeing the device through USB. What was going on? Did some update happen? Was this caused by the fact that I have a jail broken iPhone? I googled the problem, looking for what software glitch caused this.

MyWI has other modes including bluetooth and wifi linking. The problem with bluetooth is that it is tricky to configure, and I couldn’t make it work. The problem with wifi is that it drains the battery very fast. I had to switch to wifi in order to keep working, but even with the phone plugged into the wall, it couldn’t charge fast enough to keep from eventually dying.

The reason for it dying like this I believe is due to low signal in the area I am in. It probably needs to resend more packets, thus consuming more power to get the same amount of information transmitted. This was becoming a big issue, because it meant I could only work for chunks of time and then had to sign off.

I kept googling, trying to see if there was some faulty setting on either the phone or the laptop that had to be repaired. I went to sleep last night really frustrated. Between sleeping and waking, my brain must have been doing some serious debugging, because when I awoke, the answer dawned on me: the USB cable may be the culprit.

I had bought a new car adapter to charge my iPhone, and the cable was definitely not an Apple product. I remember how sometimes it even seemed fickle when I connected that cable to the AC adapter to charge it. It also was flaky in whether or not it would charge when connected to the laptop. When I woke up this morning, it was as if all this was laid before my eyes, and it became obvious.

I drove to the nearest Apple retailer, bought a new power supply, got home, and plugged it in. Voila! It worked perfectly. Flipped MyWI over to USB mode and it worked effortlessly to link me to the internet. iTunes popped up, synched, and then stayed connected. It was really embarrassing to think how much time I spent searching for the software solution, when it turned out that the cable truly was the weakest link in the chain.


Submit a Comment

Your email address will not be published. Required fields are marked *