■ FIGURE 3. The Cam Tim
trigger circuit along with
the C5000-Zoom remote
and battery pack
sends out a trigger signal
every few seconds. Of
course, this is a very
basic circuit and code.
You could also program the PIC to perform other
complicated functions including using an external trigger
to start the time-lapse using the unused pins from PORTA.
Yet another possibility would be to use the interrupt signal
when the status of PORTB changes to modify the inter-frame interval. This would prevent the necessity of
restarting the circuit after every interval selection.
I built the entire circuit on a RadioShack PCB using the
parts given in Table 1, and placed it securely inside a metal
container. It is also best to mount the PIC on female
headers to simplify the task of reprogramming. You can see
some of the time-lapse movies I have taken using Cam Tim
at: http://ziggrid.com/Cam Tim/tlapse. The PCB layout is
available from: http://ziggrid.com/Cam Tim/pcb. NV
The source code is available at
and on our website www.nutsvolts.com.
5 reflectance sensors on underside
robot diameter is 3π cm (~ 3. 7 inches)
February 2009 43