■ While “Load script from file…” is highlighted in the
CHDK menu, press the FUNCT. SET button a second time
to display a list of scripts saved on the SD card.
At this point, the SD card is ready to be put back into
the camera. When the camera is started with a locked SD
card installed with CHDK, a splash screen briefly displays.
You can ignore CHDK if you wish and operate the camera
manually; you are not required to use the CHDK scripts if you
don’t want to. However, I was ready to edit and test my first
scripts. There are dozens of scripts available online, so you
don’t have to create your first script from scratch. I recommend
using an existing script and editing it for your purposes.
Recall that uBASIC commands are written into the
scripts that set camera features and automate functions.
Remember, scripts make it possible to trigger a sequence
of photographs with varying parameters.
You write scripts in Notepad or any other editor that
■ Scroll up and down the list until the desired script is
highlighted. Then, press the start button. The camera lens
will open and extend, and the script waits for the shutter
button to be pressed. Pressing the shutter button then
activates the script. Once a script is started, the LCD screen
displays STARTED at the bottom. To stop the script,
press the shutter button a second time. You can shut a
camera off at any time by pressing the power button.
does not add special characters to the file or document.
You save completed scripts as .BAS files by clicking Save
As, selecting All files in the Save As Type window, and
typing the full name of the script in the File Name
window. Be sure to save the file on the SD card under SD
That’s a beginning for using CHDK. Next time, I’ll
discuss some of the uBASIC commands and the USB
remote I created for my A550. I’ll also show you how I
modified a BalloonSat Mini flight computer to use a USB
to trigger my camera on near space missions.
Onwards and Upwards,
Your near space guide NV
Order online at:
Development Tools for PIC® MCUs
microEngineering Labs, Inc.
Phone: (719) 520-5323
Fax: (719) 520-1867
Colorado Springs, CO 80960
With Accessories for $119.95:
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