I2C more than one device MCP23017

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pitchout
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I2C more than one device MCP23017

#1 Post by pitchout » 06 Nov 2021, 11:08

hello, i have problems with my version of espeasy on wroom32. I can only operate one device in I2C (mcp23017). Do you have an idea ? If I connect two mcp23017, the esp becomes very slow and or hangs. Thank you

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Ath
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Re: I2C more than one device MCP23017

#2 Post by Ath » 06 Nov 2021, 12:09

What does the I2C scanner show?
How have you configured the I2C address of both MCP23017 modules (probably you changed jumpers), as they need to have different I2C addresses.
/Ton (PayPal.me)

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Re: I2C more than one device MCP23017

#3 Post by TD-er » 06 Nov 2021, 12:15

Most boards with I2C chips also have pull-up resistors on them.
If you add multiple boards to the I2C bus, it is possible the netto pull-up resistance becomes too low.
Do you have more I2C devices connected to the ESP?
If so, please check with only the MCP modules connected.

And of course look at the addresses as already suggested.

pitchout
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Re: I2C more than one device MCP23017

#4 Post by pitchout » 06 Nov 2021, 13:15

solved, I'm ashamed :-( an area of ​​my breabord was not powered ... pffff amateur Thanks to yu and have a nice weekend.

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Ath
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Re: I2C more than one device MCP23017

#5 Post by Ath » 06 Nov 2021, 13:19

Glad it is solved :)
/Ton (PayPal.me)

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