40 lines
1.4 KiB
Markdown
40 lines
1.4 KiB
Markdown
This is a library for the MCP23017 I2c Port Expander
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These chips use I2C to communicate, 2 pins required to interface
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Adafruit invests time and resources providing this open source code,
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please support Adafruit and open-source hardware by purchasing
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products from Adafruit!
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Written by Limor Fried/Ladyada for Adafruit Industries.
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BSD license, check license.txt for more information
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All text above must be included in any redistribution
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To download. click the DOWNLOADS button in the top right corner, rename the uncompressed folder Adafruit_MCP23017. Check that the Adafruit_MCP23017 folder contains Adafruit_MCP23017.cpp and Adafruit_MCP23017.h
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Place the Adafruit_MCP23017 library folder your <arduinosketchfolder>/libraries/ folder. You may need to create the libraries subfolder if its your first library. Restart the IDE.
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Pin Addressing
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==============
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When using single pin operations such as _pinMode(pinId, dir)_ or _digitalRead(pinId)_ or _digitalWrite(pinId, val)_ then the pins are addressed using the ID's below. For example, for set the mode of _GPB0_ then use _pinMode(8, ...)_.
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Physial Pin #| Pin Name | Pin ID
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----|------|------------------------------
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21 | GPA0 | 0
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22 | GPA1 | 1
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23 | GPA2 | 2
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24 | GPA3 | 3
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25 | GPA4 | 4
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26 | GPA5 | 5
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27 | GPA6 | 6
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28 | GPA7 | 7
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1 | GPB0 | 8
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2 | GPB1 | 9
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3 | GPB2 | 10
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4 | GPB3 | 11
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5 | GPB4 | 12
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6 | GPB5 | 13
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7 | GPB6 | 14
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8 | GPB7 | 15
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