Adafruit 7 Segment Clock Type Display

The Adafruit 7 segment clock display provides a four digit display with colons with an i2c interface. It is used by including the Wire.h, Adafruit_LEDBackpack.h and Adafruit_GFX.h libraries.

Library Functions

digit

Digits 0 and 1 are the left had pair if the display, digit 2 is the colon collection and digits 3 qnd 4 are the right hand pair.

.clear()

This clears the display buffer. Don't forget to call .writeDisplay() subsequently to update the display from the display buffer.

.writeDigitNum(digit, value)

This writes the value to the digit position specified on the display. The value can be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, b, C, d, E and F. Values outside this range are displayed as spurious symbols. CHECK THIS

.writeDigitRaw(digit, bitmask)

The bitmask for normal digits is assembled by adding the values of the segments you want to effect thus…

         __1__
        |     |
        32    2
        |     |
         __64_ 
        |     |
        16    4
        |     |
         __8__   . 128

E.g. to display the letter S the bitmask should be 1 + 4 + 8 + 32 + 64 = 109 so the call to the function should be .writeDigitRaw(digit, 109);

.writeDisplay()

This updates the physical display from the display buffer. It must be called after chaging the contents of the display buffer before any changes can be seen.