PCF8574 Inputs

Discuss development of drivers for external hardware and components, such as LCD screens, sensors, motor drivers, etc.
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mattnelson
Posts: 1
Joined: Mon Apr 17, 2017 7:42 am

PCF8574 Inputs

Post by mattnelson » Mon Apr 17, 2017 7:50 am

Has anyone used the PCF8574 as an input expander?
I've tried this library, https://github.com/BetaRavener/micropyt ... er/PCF8574 and have been successful using it to turn on LEDs etc, but can't seem to get inputs working. pcf.read8() returns a [0] regardless of input status.
Thanks.

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mcauser
Posts: 507
Joined: Mon Jun 15, 2015 8:03 am

Re: PCF8574 Inputs

Post by mcauser » Wed Apr 19, 2017 2:24 am

Using it to drive 16x2 LCDs, using a LCD backpack, as an output expander:
https://github.com/dhylands/python_lcd/ ... i2c_lcd.py

I have a generic one which is not attached to a LCD.
https://www.aliexpress.com/item/PCF8574 ... 58823.html

Never used it for input though, only output.
I'll try to get it working with the library and share my results.

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