Shift Seven

Johnny-Five module for controlling a seven segment display with a shift register.

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Getting Started

Shift Seven components must have the shift register pins connected to the seven segment pins in a specific order. Naming the shift register bits A - H, the pins should map to their same-named pins on the seven segment display, with H mapping to DP on the display.

Note: The DP pin is not used for drawing any numbers. However, you may use this when drawing with a custom binary string via ShiftSeven#write().

Image source: Wikipedia, licensed CC BY-SA 3.0

Frizting digram: shift-seven.fzz

API

new ShiftSeven(options)

Creates a new ShiftSeven instance.

• options (Object): The options for initializing the display.
  • pins (Object): The pins for the shift register.
    • data (Number): The data pin.
    • clock (Number): The clock pin.
    • latch (Number): The latch pin.
  • board (Object; optional): Which board the shift register is connected to.

var display = new ShiftSeven({
	pins: {
		data: 2,
		clock: 3,
		latch: 4
	}
});

ShiftSeven#draw(number)

Draws a number on the seven segment display.

• number (Number): The number to draw, from 0 to 9.

display.draw(5);

ShiftSeven#write(value)

Draws the specified segments on the display.

• value (String|Number): A bitmask or eight character binary string representing the segments to draw.
  • The string form must contain only 0s (for off) and 1s (for on). The string is ordered the same as the shift register, from pins A - H (A - G, DP on the display).

display.write("11101110");
// or
display.write(238);

ShiftSeven#off()

Turns off the display.

display.off();

new ShiftSeven.Multi(options)

Creates a new ShiftSeven.Multi instance to create a multi-digit display from multiple shift register/seven segment display pairs.

• options (Object): The options for initializing the display.
  • leadingZeros (Boolean; optional; default: false): Whether leading zeros should be written when the currently drawn number doesn't require all segments.
  • displays (Array): Array of ShiftSeven options for each individual shift register/seven segment display pair.

var display = new ShiftSeven.Multi({
	leadingZeros: true,
	displays: [
		{
			pins: {
				data: 2,
				clock: 3,
				latch: 4
			}
		},
		{
			pins: {
				data: 8,
				clock: 9,
				latch: 10
			}
		}
	]
});

ShiftSeven.Multi#draw(number)

Draws a number on the seven segment displays.

• number (Number): The number to draw, from 0 to 10^(display count) - 1.

display.draw(25);

ShiftSeven.Multi#off()

Turns off the display.

display.off();

License

Copyright Scott González. Released under the terms of the MIT license.

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