Computing - Input & Output Devices
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Flashcards
2020-11-30
What’s an example usage of barcodes?
- Airline baggage tracking
- Product labelling
- Parcel delivery and shipment
- Ticketing and identification
What concept allows barcode readers to work?
Reflected light
What does a black bar represent in a barcode?
Why does black represent $0$ in barcodes?
Black reflects less light.
What does a white bar represent in a barcode?
Why does white represent $1$ in barcodes?
White reflects more light.
What does UPC-A stand for?
Universal Product Code Version A
What is UPC-A?
A barcode standard.
What does EAN stand for?
European Article Number
What are the two common standards for product barcodes?
- UPC-A
- EAN
What are “Code 128” barcodes used for?
Transport and shipment tracking.
What does the large left number represent?
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The manufacturer number.
What does the large right number represent?
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The product number.
What is the far right number?
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This image contains identical bars at the beginning, middle and end. What are these called?
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Guard bars.
Why is the left hand side and the right hand side the exact opposites?
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So that the orientation doesn’t matter.
If you have $0010$ on one side of a barcode, what do you have on the other?
What does $QR$ stand for?
Quick Response
What does $CCD$ stand for?
Charge-Coupled Device
What does $CMOS$ stand for?
Complementary Metal Oxide Semiconductor
What is better: A $CCD$ or $CMOS$?
A $CCD$.
What is a $CCD$ or a $CMOS$?
The sensor in a camera.
What are the two types of camera sensors?
- CCD
- CMOS
What happens when a camera’s shutter opens?
The light hits the sensor and the light values are represented as binary values.