Shared by adachsoft on Instructables:

This guide shows you how to use PCF8574 with Raspberry PI. The PCF8574 is a 8 bits I/O port expander that uses the I2C bus. To the PCF8574 I will connect the relay module, this will allow control of the electrical device from the Raspberry PI. I will also show an example how to write a program to handle PCF8574 in C++ on Linux.

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Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!

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Raspberry Pi 3 – Model B – ARMv8 with 1G RAM – Did you really think the Raspberry Pi would stop getting better? At this point, we sound like a broken record, extolling on the new Pi’s myriad improvements like we’re surprised that the folks at the Raspberry Pi foundation are continuously making their flagship board better. Still, we’ll say it again – the Raspberry Pi team have outdone themselves. The Raspberry Pi 3 Model B is out and it is AMAZING.
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