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Pin 9 and 14 linked should be be connected to ground. VREF (15) and VDD should be connected to your VCC(3.3v)
Libraries
| Library | URL |
|---|---|
| MCP3008 by Uros Petrevski | https://github.com/nodesign/MCP3008 |
| MCP3008 by Adafruit | https://github.com/adafruit/Adafruit_MCP3008 |
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