Still alive, power problems
July 8, 2011
I'm not dead, I just had a little foul up with my Baby Orangutan and never got around to ordering a new one.
The Baby Orangutan is a very tiny robotics controller, complete with an AVR chip, motor controller and the Pololu library for robotics. It's also really tiny, so if you don't need all the stuff on the larger Orangutan controllers, it's really ideal. Just solder on the headers, get some female jumper wires and plug stuff in. The problem I had was with the labels. The board's labels are on the bottom of the board. I thought "OK, I'll just solder the headers onto the board upside down!" And that worked just fine, except the 2x3 header for the ICSP programmer. I didn't consider the fact that that would be mirrored, and my programmer wouldn't work. And I don't have the equipment to desolder those headers, at least without damaging the tiny board, so that one is just wasted (but I'm sure I can recycle it later).
So I ordered a new one and soldered the pins on right this time. Or, by "right" I mean "not how the picture shows, but how I needed." It's intended to plug into a breadboard, but I solder the long parts of the headers facing up, so I can plug female jumper wires into it. It works just fine that way. But now I run into a problem. The first thing I try to control is the servo motor. However, as soon as this servo motor moves, the microcontroller resets. I'm assuming this is a power problem, and I'll have to make a small "power supply" board. The MCU board already has its own regulator, but I'm assuming the power drop is too much for it to handle. I'll need an array of smoothing caps. But this helps me solve another problem I've been having: how to provide a way to plug all the power connectors in. I rigged up some horrible looking thing with wires, but having a board with headers to plug into will just be better.
The alternative is to have a second power supply, but from what I can see, that's not possible with the Baby Orangutan. It takes a single power supply and doesn't expose the pins for an alternate motor supply from the H-bridge. So even if I did power the servo motor from another supply, I'd have the same problem as soon as I tried to power my motors from my H-bridge.
But, at any rate, I'm back to working on this.