7-segment display
Seven-segment display: inputs a–g each light one stroke, together forming digits.
Pins
Seven inputs on the left: a, b, c, d, e, f, g.
How to use it
Usually paired with the Hex to 7-segment decoder: feed it a 4-bit number, then wire a–g across one to one.
Usage example
The a–g pins each light one segment. It's usually paired with the hex-to-7-segment decoder: feed in 4 bits (0101 here) and it shows 5.
Common mistakes
Lighting segments one switch at a time is tedious — use the decoder instead.