October 27, 2009

The new 8gb SD card came in today, and I spent the last hour or so poking around, trying to get CHDK to work on it. I knew that it was possible, and I eventually found a way that worked for me buried in this topic on the CHDK forums.

Basically, it seems that CHDK needs to be booted off of a FAT16 partition, but FAT16 only supports partitions up to 4gb. In order to use a larger memory card, you need to set up two partitions; a small FAT16 one to boot CHDK, and a larger one (the rest of the available space) which is FAT32 to store images. The problem is, if you use Windows, you aren’t able to partition an SD card like you could a hard drive, and so you need to turn to third party utilities.

A common tactic seems to be to use custom drivers for your card reader, which makes windows treat your SD card as a local drive, allowing all normal actions like partitioning. This approach didn’t work for me, possibly because I am using the 64 bit version of Windows, or possibly because I am using Windows 7, but whatever the case, no luck there.

Another approach is to use a Lexar tool to make windows think your removable drive is a local drive; this didn’t work for me either, possibly because I’m not using a Lexar card reader.

What did work for me, and seems to be the simplest approach, is a tool included in StereoData Maker, a CHDK based setup for taking stereo images. On that page is a “common_files.zip” that contains a file called “sdminste.exe”. This program set up my SD card with 2 partitions that I am able to switch between; a 2mb one for CHDK, and a ~7.5gb one for storing images. I installed the “Small” version of CHDK to the 2mb partition, and installed the “CHDK” folder from “Complete” on the larger partition. A slight issue with this setup is that you need to swap the partitions back and forth with the SDM program to get at the images on Windows, however accessing them over USB cable directly from the camera works fine.

There’s a lot of information here that’s not really presented in the most useful way. Once I finish with Flight 1.0, I’ll put together a comprehensive step-by-step guide with everything I learned and put that up on the site. If anyone wants any information before then, just use the Contact Me page and I’ll respond as soon as I can. That’s all for now, still planning to get some pictures up sometime soon!