H bridges, minor failure and troubleshooting

When I left off last time, I was raring to go with some sample PID code that allowed me to test out a basic movement between two points. I realised I hadn't included any wiring, and that's important for this post. Suffice to say, the code didn't work quite as I had intended, but not for obvious reasons. By that, I mean I spent hours trying to debug what was going on without success. Instead, I had to break out the oscilloscope and measure to find out what was really happening.

Motion control - H bridges and movement

In my last post I was talking about getting the feedback mechanism from a printhead carriage up and working. This enabled me to track how much relative movement of the carriage had occurred, but didn't enable me to make the thing move! That comes in this part. In order to get motion happening, I need something that can handle the voltages/currents the motor needs - a job for an H bridge!