Create README.md

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Trinket_React_Counter/README.md

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+## TrinketReactCounter
+Trinket sketch to build a react or 'like' button that counts button presses and
+displays them on a 7-segment or 14-segment LED backpack.
+
+The files in this repository accompany an [Adafruit Learning System](https://learn.adafruit.com) tutorial 
+https://learn.adafruit.com/trinket-react-counter
+
+This code was formerly at https://github.com/adafruit/TrinketReactCounter - this has now been archived.
+
+All code MIT License, please keep attribution to Adafruit Industries
+
+If you are looking to make changes/additions, please use the GitHub Issues and Pull Request mechanisms.
+
+Please consider buying your parts at [Adafruit.com](https://www.adafruit.com) to support open source code.
+
+## Hardware
+
+You need the following hardware to build this device:
+
+*   [Adafruit Trinket](https://www.adafruit.com/trinket) (either the [5V Trinket](https://www.adafruit.com/products/1501) or [3.3V Trinket](https://www.adafruit.com/products/1500) will work)
+*   [Adafruit 7-segment LED Backpack Display](https://www.adafruit.com/product/879) or [Adafruit 14-segment quad alphanumeric LED Backpack Display](https://www.adafruit.com/product/1911)
+*   [Momentary push button](https://www.adafruit.com/products/1009)
+
+Connect the hardware as follows:
+
+*   Trinket 3V/5V power to 7-segment power (+) and one side of the button.  If
+    using the 14-segment display connect 3V/5V power to the additional power (+) pin.
+*   Trinket #0 to 7-segment SDA (D).
+*   Trinket #1 to opposite side of button.
+*   Trinket #2 to 7-segment SCL (C).
+*   Trinket GND/ground to 7-segment ground (-).
+
+## Usage
+
+Load the right sketch in Arduino depending on your hardware.  The 7-segment display
+should use the TrinketReactCounter_7segment sketch, and the 14-segment quad alphanumeric
+display should use the TrinketReactCounter_14segment sketch.  Make sure the following
+libraries are installed too (using the library manager or a manual install):
+
+*   [Adafruit GFX Library](https://github.com/adafruit/Adafruit-GFX-Library)
+*   [Adafruit LED Backpack](https://github.com/adafruit/Adafruit_LED_Backpack)
+
+For your first use uncomment this line near the top of the sketch:
+
+    // Uncomment the line below to reset the counter value in EEPROM to zero.
+    // After uncommenting reload the sketch and during the setup the counter
+    // will be reset.  Then comment the line again and reload to start again
+    // (if you don't comment it out then every time the board powers on it
+    // will reset back to zero!).
+    //#define RESET_COUNT
+
+So that it looks like the following:
+
+    // Uncomment the line below to reset the counter value in EEPROM to zero.
+    // After uncommenting reload the sketch and during the setup the counter
+    // will be reset.  Then comment the line again and reload to start again
+    // (if you don't comment it out then every time the board powers on it
+    // will reset back to zero!).
+    #define RESET_COUNT  
+
+This will cause the count stored in EEPROM to be reset to zero during the setup.
+
+Save and upload the modified sketch to the Trinket.  You should see the display print 0.
+If you press and release the button the count should increment by one.
+
+Now back in the sketch code comment out the RESET_COUNT line again so it looks
+like its original value:
+
+    // Uncomment the line below to reset the counter value in EEPROM to zero.
+    // After uncommenting reload the sketch and during the setup the counter
+    // will be reset.  Then comment the line again and reload to start again
+    // (if you don't comment it out then every time the board powers on it
+    // will reset back to zero!).
+    //#define RESET_COUNT
+
+Upload the sketch to the Trinket again.  You should see the display print the
+previous count value, and again pressing the button will increment the count.
+Now if you power down and then power back up the Trinket it should load the
+last count value after the bootloader runs (the red light stops pulsing).
+
+You can follow the above steps to uncomment the RESET_COUNT value any time you
+want to reset the count value back to zero.