sevensegment

README

sevensegment

Golang module for controlling the Adafruit seven segment LED display with backpack (HT16K33 i2c), using golang's periphio.

Note this was developed for use on a raspberry pi.

Examples of how to use are in example.go which does some simple tasks such as displaying numbers digits at specific positions, displaying a number up to 9999, letters, particular segments and setting the brightness.

eg. (assuming device addr on i2c bus is 0x70)

go mod init main
go run example.go

References and links

periphio (i2c)
https://periph.io/
https://godoc.org/periph.io/x/periph/conn/i2c

Adafruit LED backpack HT16k33 datasheet (info about commands/settings for the HT16K33)
https://cdn-shop.adafruit.com/datasheets/ht16K33v110.pdf

Adafruit LED backpack C/C++ library
https://github.com/adafruit/Adafruit_LED_Backpack

Documentation

Index

• Constants
• func NumToArray(number int) []int
• type SevenSegment
  • func NewSevenSegment(addr byte) (ss *SevenSegment)
  • func (ss *SevenSegment) AlphaToSegments(letter byte) uint16
  • func (ss *SevenSegment) ArrayToSegments(segments_on [7]bool) uint16
  • func (ss *SevenSegment) Clear()
  • func (ss *SevenSegment) DisplayOn()
  • func (ss *SevenSegment) HwPos(human_pos int) int
  • func (ss *SevenSegment) IntToSs(digit int) uint16
  • func (ss *SevenSegment) OscillatorOn()
  • func (ss *SevenSegment) SetAlpha(pos int, letter byte)
  • func (ss *SevenSegment) SetBrightness(brightness int)
  • func (ss *SevenSegment) SetDigit(pos int, digit int)
  • func (ss *SevenSegment) SetNum(number int) (err error)
  • func (ss *SevenSegment) SetSegments(human_pos int, on [7]bool)
  • func (ss *SevenSegment) WriteData()
  • func (ss *SevenSegment) WriteRaw(data []byte)

Constants

const (
	IndMidTop   = iota
	IndMidBtt   = iota
	IndLeftTop  = iota
	IndLeftBtt  = iota
	IndRightTop = iota
)

Dot LED indicators on Segment 4

Functions

func NumToArray

func NumToArray(number int) []int

Return array (reverse order) of digits for a given 1-4 digit number

Types

type SevenSegment

type SevenSegment struct {
	Buffer [10]uint16
	// contains filtered or unexported fields
}

Sevensegment with a buffer to hold desired segment state

func NewSevenSegment

func NewSevenSegment(addr byte) (ss *SevenSegment)

func (*SevenSegment) AlphaToSegments

func (ss *SevenSegment) AlphaToSegments(letter byte) uint16

Return 2 byte value which segments should be on for a supplied letter

func (*SevenSegment) ArrayToSegments

func (ss *SevenSegment) ArrayToSegments(segments_on [7]bool) uint16

Return 2 byte value representing which segments are on for supplied array of 'on' segments

func (*SevenSegment) Clear

func (ss *SevenSegment) Clear()

Clear all segments

func (*SevenSegment) DisplayOn

func (ss *SevenSegment) DisplayOn()

Command to turn on display is 0x81

func (*SevenSegment) HwPos

func (ss *SevenSegment) HwPos(human_pos int) int

Translate human pos on display (0 - 4) to corresponding rows in HT16K33 mem that reference a digit or colons, pos 5 is colons.

func (*SevenSegment) IntToSs

func (ss *SevenSegment) IntToSs(digit int) uint16

Returns 2 byt val representing the data required to turn segments on for supplied 'digit' similar to numbertable at: https://github.com/adafruit/Adafruit_LED_Backpack/blob/master/Adafruit_LEDBackpack.cpp

func (*SevenSegment) OscillatorOn

func (ss *SevenSegment) OscillatorOn()

Command to turn on oscillator

func (*SevenSegment) SetAlpha

func (ss *SevenSegment) SetAlpha(pos int, letter byte)

Set letter at position from 0 to 3 from right to left

func (*SevenSegment) SetBrightness

func (ss *SevenSegment) SetBrightness(brightness int)

Set brightness from 0-15

func (*SevenSegment) SetDigit

func (ss *SevenSegment) SetDigit(pos int, digit int)

Set digit at position from 0 to 3 from right to left

func (*SevenSegment) SetNum

func (ss *SevenSegment) SetNum(number int) (err error)

Set a number on the display up to 9999. A negative number will result in --- being displayed.

func (*SevenSegment) SetSegments

func (ss *SevenSegment) SetSegments(human_pos int, on [7]bool)

Set specific segments on for digit at pos 0 to 3 from right to left To determine which segments, we label the segments 0-6 starting from topmost horizontal, incrementing clockwise to 5, and 6 is the middle horizontal and specify which are on in an array

func (*SevenSegment) WriteData

func (ss *SevenSegment) WriteData()

Write out my buffer, this will actually display segments

func (*SevenSegment) WriteRaw

func (ss *SevenSegment) WriteRaw(data []byte)

Write raw data to bus, useful for setting up the seven segment