need help connecting Huzzah Feather to MCP3008

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jfhallst
 
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need help connecting Huzzah Feather to MCP3008

Post by jfhallst »

can anyone tell me the specific pin to pin setup for connecting an MCP3008 to a huzzah feather? I've been able to find youtube videos on how to do it with a generic NodeMCU ESP8266 but the pins aren't labelled the same and I'm too much of a novice to understand how to translate to the Feather pins.

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adafruit_support_carter
 
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Re: need help connecting Huzzah Feather to MCP3008

Post by adafruit_support_carter »

You can use this library if programming with Arduino:
https://github.com/adafruit/Adafruit_MCP3008
and there's a table with wiring connection info in the readme.

Here's an example wiring:
wiring.jpg
wiring.jpg (1.16 MiB) Viewed 452 times
and output from the example sketch in library (note: pot connected to first channel only):
sample_out.jpg
sample_out.jpg (41.8 KiB) Viewed 452 times

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jfhallst
 
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Re: need help connecting Huzzah Feather to MCP3008

Post by jfhallst »

I connected the MCP3008 to the Feather Huzzah as specified at https://github.com/adafruit/Adafruit_MCP3008. I've got a pot connected to Channel 1 and am getting readings, but they're random values between 0 and 1023 and don't appear to be affected when I turn the pot. All connections are to a rail connected to a breadboard power supply that's producing a rock steady 3.19 volts. I've tried multiple pots and all respond the same way. I'm very much a novice at this so am clueless about how to trouble shoot.

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jfhallst
 
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Re: need help connecting Huzzah Feather to MCP3008

Post by jfhallst »

Update: I disconnected the breadboard power supply so I'd be running solely from USB. the values stopped jumping around, but now the input from the pot cycles up and down irregularly regardless of where I set it. If I disconnect the pot entirely, the output will cycle between 0 and about 20. the cycles are also irregular. tried pot on different inputs to MCP3008. Also tried the pot with a teensy and it worked fine. Image attached
MCPhookup.jpg
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adafruit_support_carter
 
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Re: need help connecting Huzzah Feather to MCP3008

Post by adafruit_support_carter »

Split power rails strike again. The pots not hooked up. Either jumper the power rails or reconnect the pot.
power_rails.png
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