A digital camera contains an embedded system.
Give two functions that the embedded system performs in the digital camera.
Mark scheme
Award one mark for any of the following up to a maximum of two marks:
- Focus the lens/autofocus (1)
- Control the shutter (speed) (1)
- Control the flash/decide when the flash is needed (1)
- Measure the light level to set the exposure/the aperture (1)
- Stabilise the lens/image stabilisation (1)
- Zoom the lens in and out (1)
- Detect a face/smile (1)
Do not accept 'take a photograph'/'take a picture'/'capture an image', as taking photographs is the function of the camera, which is given in the question.
Do not accept 'press the button' as this is an action of the user, not a function performed by the embedded system.
Do not accept vague answers such as 'use the camera', 'turn the camera on and off' or 'make the camera work', which do not name a function that the embedded system performs.
Example answers and how they were marked
It focuses the lens and decides when the flash should fire.
Why: Focus the lens (1) and control the flash (1).
It controls the zoom and takes a picture when the button is pressed.
Why: Zoom the lens credited (1); 'takes a picture' is not accepted because taking photographs is the function of the camera, which is given in the question, and 'press the button' is the user's action, not a function of the embedded system.
It takes a picture when the button is pressed and it makes the camera work.
Why: No mark: 'takes a picture' repeats the camera's function given in the question, 'press the button' is an action of the user, and 'makes the camera work' is too vague to name a function.