Si Ballenger said:
I checked the page and it sounds like an interesting project.
I've got a pan/tilt cam at the below page with links to how I do
it. Simple stuff that should be equally transportable to linux.
My problem is finding a dead simple and inexpensive way to
program a PIC or AVR to control the servos (I use a mini-ssc II
controller currently). Just can't seen to get things to line up
for a success.
http://www.geocities.com/zoomkat/ppswitcher-demo.htm
What, does everyone have a pan/tilt cam project? Probably.
Mine currently uses a 16F84, but I've been looking with interest Motorola's
68HC908QT1:
http://e-www.motorola.com/webapp/sps/site/prod_summary.jsp?code=68HC908QT1&nodeId=03t3ZGpnLn84498634
You'll have to cut and paste that link, I believe. Anyway, it's an 8-pin DIP
or SOIC, with 5 I/O pins and 1 input-only pin. It's also programmable
in-circuit; you can set it to enter low-voltage programming mode when pins
are pulled into certain states during startup. I think an ideal solution
would be to some of the control pins, say DTR and RTS on the serial port, to
reset the microcontroller and enter programming mode. You'd be able to
reprogram the device by merely running the right program, no jumpers
necesary and you don't have to pull the chip and stick it in a programmer.
It's also extremely cheap, 70 cents from Motorola in quantity and $2.02 from
Digikey. It has an internal oscillator you can use, but the error is +-5%
and might not be acceptable for serial comms. Seems like a neat little
low-cost chip that doesn't have any more pins than you need to control a few
servos, and can be programmed in-circuit.