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Connecting LCD to Adabox004 project
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Connecting LCD to Adabox004 project

by cfshufeldt on Sat Jul 08, 2017 9:40 am

I was hoping to connect my 16x2 LCD from Adabox001 as part of an Adabox004 project. This would allow the project to display what you are listening to. With the IR sensor hooked up, I only see 4 unused logic pins on the Huzzah ESP8266 Feather: 1, 3, 5 and 17. The LCD needs 6 logic pins so I think I'm out of luck. Is this right or am I missing something?

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Re: Connecting LCD to Adabox004 project

by adafruit_support_mike on Sat Jul 08, 2017 11:40 pm

Yeah, I think you're hitting the limits of pin count. You can connect an I2C GPIO extender like the MCP23008 or MCP23017:

https://www.adafruit.com/product/593
https://www.adafruit.com/product/732

and control the LCD with that. It will only cost two pins, and those can be shared since they're the I2C bus. That's pretty much what we do with the LCD Shield.

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Re: Connecting LCD to Adabox004 project

by oscarinho on Mon Oct 09, 2017 11:59 am

I'm trying to make a led blink from the pins mention here, only getting my results with pin 5. Is there something extra I should do to use 1, 3 and 17?

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Re: Connecting LCD to Adabox004 project

by adafruit_support_mike on Mon Oct 09, 2017 11:44 pm

Pins 1 and 3 are the Serial interface, and are connected to the CP2104 USB-to-Serial converter. You can probably use them while the Feather is disconnected from a computer, but if you plug in a USB cable those pins belong to Serial.

Pin 17 is the ADC, and I think that's limited to 1v signals.

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Re: Connecting LCD to Adabox004 project

by oscarinho on Thu Oct 12, 2017 10:44 pm

Thanks Mike. I manage to use a shift register and power 8 leds. Enough for my little project.

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Please be positive and constructive with your questions and comments.