Category: Technical Articles

August 1, 2010 / / Electronics
Meet the LaunchPad

I’ve been playing with the TIĀ LaunchPad the last day or two since I’ve been home in the US. I ordered two when they launched, but I was abroad and only just started playing with them, and I have some first impressions to share.

January 11, 2010 / / iPhone
Debugging on device. Freaking finally.
Debugging on device. Freaking finally.

UPDATE: There’s a new method for iOS4 but they’re pretty similar anyway.

So it’s been a while, but now that I’m on break again and have some time, I’m doing a bit of iPhone development again. That means I’m going to need to debug on-device (or at least load my app to it to have fun in the real world with my handiwork). This time, the procedure’s a little different though.

Vital stats:
iPhone OS 3.1.2
Xcode version 3.2.1, 64 bit
Mac OSX 10.6.2 Snow Leopard

Let’s do it.

UPDATE: Corrected a problem with the run script build phase: corrected the directory names for the new version and copied the new phase that doesn’t include “resource_rules.plist.”

UPDATE 2: Somehow I forgot the add an identity step. It’s now #1 below. Sorry guys. Also, while this whole thing should apply to iPhoneOS 4, I’m going to officially text it/repost with 4.01 soon.

ARG! It's stuck!
ARG! It’s stuck!

So maybe this is the dumbest, easiest thing in the world and I’m the only one who didn’t know, but when I upgraded to the iPhone OS 3.0 SDK, I couldn’t for the life of me get the simulator to launch in ACTUAL OS 3.0 mode. You can change the version on the fly with the Hardware>Version menu, but every time I reran my app from Xcode, it’d revert back to 2.2.1. This finally became a problem when I needed to test an app with features unique to 3.0. Luckily, the fix isn’t all that hard.

July 18, 2009 / / Electronics
Yay bench power!
Yay bench power!

WARNING WARNING WARNING! Switching power supplies have many BACs (beefy-ass capacitors) that can hold lots of juice long after you’ve unplugged the unit. Do not crack one open like I did without knowing what you’re doing, it could seriously injure you or at least be really uncomfortable when you shock the crud out of yourself. I’m not responsible if you do just that, don’t say I didn’t warn you. I have a cable I made with a brush at the end that grounds everything it touches, I use it to brush the back of all power electronics before I work on them. You should too.

This is a pretty common one, but I like to add flair. I needed a bench power supply. Sadly, bench power supplies are very expensive, and I’m a poor college student. What I do have are computers. Lots of computers. In fact, I just brought to the recyclers about 100lbs of computer waste from machines that are too slow for even my standards. Luckily, one thing computers have going for them is very refined, VERY powerful power supplies.

July 18, 2009 / / Electronics
USB metering goodness.
USB metering goodness.

A while back I wanted to monitor how much current my iPhone could draw under different conditions. I had seen a cable before where somebody brought it into a project box with a couple of screws on top exposing the two unshorted positive leads and the straight-through ground (such that you could measure both current through the cable or voltage across it), but I felt I could make things both smaller and more fully-featured.

July 18, 2009 / / Electronics