The 74HC595 is a 8 input channel multiplexer. It is exceptionally useful when you need to expand your inputs. This allows you to convert 1 serial byte into 8 outputs. The 74HC595 also allows you to cascade these devices for more bits.
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The 74HC595 is a 8 input channel multiplexer. It is exceptionally useful when you need to expand your inputs. This allows you to convert 1 serial byte into 8 outputs. The 74HC595 also allows you to cascade these devices for more bits. You will need three pins, serial, serial clock, and a latch.