Initiates an async download of a specific file from the SD card to the host PC.
Returns immediately; completion is signaled via the downloadComplete SSE event
(remote/remote-transfer modes) or via filesystem polling (contents-transfer mode).
Documentation Index
Fetch the complete documentation index at: https://crsdk.app/llms.txt
Use this file to discover all available pages before exploring further.
Camera identifier (e.g. D10F60149B0C)
SD card slot number (1 or 2)
1, 2 SDK content identifier from listSDCardFiles response
SDK file identifier from listSDCardFiles response (always 0 in contents-transfer mode)
Optional save path override. If omitted, uses the connection-time SetSaveInfo path.
Directory path on host PC to save the file
"/Users/me/Pictures/captures"