(Electronic Development Software Development Kit) is Canon’s official SDK for developers to control Canon EOS cameras remotely via USB (e.g., for tethered shooting, intervalometers, custom live view apps).
, it is not "freeware" in the traditional sense; it requires an application and approval process through Canon’s developer relations Quick Verdict canon edsdk free download
Adjust ISO, aperture, shutter speed, and focus remotely. for tethered shooting