Component: 7Segment (Single) (Segment)

Author	Matrix Ltd
Version	1.4
Category	Segment

7Segment (Single) component

Seven segment display modelled after a standard 14mm high unit. LED colour can be changed in properties.

Component Pack

DISPLAYS

Detailed description

No detailed description exists yet for this component

Examples

Each segment will require a current limiting resistor.

This LED Calculator tool is a good resource for calculating the correct LED series protection resistor.

LED Resistor Calculator Tool

Simple Counter

This example counts up from 0 to 9 on the 7-segment display before wrapping back to 0 and starting again. When displaying odd numbers we light the decimal point segment. 7Segment Display Example

Multiplexed Counter

This next example counts up from 0 to 99 on two 7-segment displays before wrapping back to 0 and starting again. The two displays are driven using a technique called multiplexing. A timer interrupt is used to perform the multiplexing leaving our program free to perform other tasks. Each 7-segment display shares the same segment pin connections but has a unique common pin connection to allow each individual 7-segment display to display a unique value. 7Segment Multiplex

Stop Watch

This next example uses a timer interrupt to multiplex between the displays and a second timer interrupt to count the passing of time allowing for accurate timings. Using four single 7-seg components we create a timer capable of monitoring time from 0.0 to 999.9 seconds in multiples of 100ms. The second timer interrupt flags to the main when the count value has changed allowing the heavier calculations to extract the digits from the counter to be done outside of the high speed interrupt routine and therefore maintain accurate timing.

Switches connected to Port D allow for the timer to be started, stopped and reset. 7Segment Timer

Segment Control

This example shows a method to display custom characters on 7-segment displays and also allows for numeric values to be displayed.

7Segment Character Demo

Downloadable macro reference

	ClearDigit
This funtion clears all the individual segments including the decimal point segment. In simulation this sets the colours to the default BGColor component variable. It's default value is 0xCCCCCC
- VOID	Return

	ShowSegments
Allows the individual segments of the display to be controlled.
- BYTE	Segments
8-bit Binary value to set the segments, bit0 = segA, bit1 = segB...
- VOID	Return

	ShowDigit
Creates the supplied digit on the 7 segment display. Macro takes the digit to display and a boolean representing whether to display the decimal point segment or not.
- BYTE	Digit
Sets the 7seg display with the appropriate digit supplied
- BYTE	DecimalPoint
Determines whether decimal point LED is active (True/False)
- VOID	Return

Property reference

	Properties
	Display Type
Set this property to match your hardware device. Common Anode: Pin true -> LED off, Pin false -> LED on Common Cathods: Pin true -> LED on, Pin false -> LED off
	Show Seg Labels
Show the identifier lables of the segments overlayed over the component.
	Common Pin
When using a single 7-segment display you can keep the common pin active by connecting it to VCC or VSS so no output pin is required. When using multiple 7-seg displays you need the common pin to allow you to multiplex between the displays.
	Common Type
The state of the output common pin when the 7-segment display is active. Usually a common cathode display uses a low signal and a common anode uses a high signal. If the common pin is routed via a transistor for power amplification then the signal may need to be reversed.
	Connections
	pin0 (A)
Pin connected to the 'A' degment of the display.
	pin1 (B)
Pin connected to the 'B' degment of the display.
	pin2 (C)
Pin connected to the 'C' degment of the display.
	pin3 (D)
Pin connected to the 'D' degment of the display.
	pin4 (E)
Pin connected to the 'E' degment of the display.
	pin5 (F)
Pin connected to the 'F' degment of the display.
	pin6 (G)
Pin connected to the 'G' degment of the display.
	pin7 (DP)
Pin connected to the decimal pointt of the display.
	common
Pin connection to the 'common' pin of the display - to allow enable/disable of the whole display.
	Colors
	LED Color
Color when an LED is turned on. When turned off, will use a much darker shade of the same hue.
	Bezel Color
Color of the plastic package housing the LEDs
	Label Color
Color of the optional segment name labels.