Canon 500D pinouts
The connector/pinout information may be applied to the Canon model 500D
Canon DSLR 300D, 350D, 400D, 450D, 500D computer manual shooter control serial cable pinout used for computerized long exposure control
Canon 350D, 400D, 450D, 500D, 550D, 60D, Pentax manual shutter/focus control pinout The external trigger can be accessed with a standard 3-pole 2.5 mm jack plug. Appropriate 'official' remote controller with this plug is called RS-60 E3 or COS-60E3. The same pinout is used by all Pentax cameras
Mini-HDMI (type C) connector pinout This miniature connector available at some camcorders and other compact multimedia devices.