epd

package
v3.6.9 Latest Latest
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 Go to latest Published: Mar 28, 2021 License: Apache-2.0 Imports: 13 Imported by: 0

Documentation

Overview

Package epd controls Waveshare e-paper series displays.

More details

Datasheets

https://www.waveshare.com/w/upload/e/e6/2.13inch_e-Paper_Datasheet.pdf

Product page:

2.13 Inch version: https://www.waveshare.com/wiki/2.13inch_e-Paper_HAT

1.54 inch version: https://www.waveshare.com/wiki/1.54inch_e-Paper_Module

Example 
// Make sure periph is initialized.
if _, err := host.Init(); err != nil {
	log.Fatal(err)
}

// Use spireg SPI bus registry to find the first available SPI bus.
b, err := spireg.Open("")
if err != nil {
	log.Fatal(err)
}
defer b.Close()

dev, err := epd.NewSPIHat(b, &epd.EPD2in13) // Display config and size
if err != nil {
	log.Fatalf("failed to initialize epd: %v", err)
}

// Draw on it.
img := image1bit.NewVerticalLSB(dev.Bounds())
// Note: this code is commented out so periph does not depend on:
//    "golang.org/x/image/font"
//    "golang.org/x/image/font/basicfont"
//    "golang.org/x/image/math/fixed"
//
// f := basicfont.Face7x13
// drawer := font.Drawer{
// 	Dst:  img,
// 	Src:  &image.Uniform{image1bit.On},
// 	Face: f,
// 	Dot:  fixed.P(0, img.Bounds().Dy()-1-f.Descent),
// }
// drawer.DrawString("Hello from periph!")

if err := dev.Draw(dev.Bounds(), img, image.Point{}); err != nil {
	log.Fatal(err)
}
dev.DisplayFrame() // After drawing on the display, you have to show the frame

Output:
Example (Other) 
// Make sure periph is initialized.
if _, err := host.Init(); err != nil {
	log.Fatal(err)
}

// Use spireg SPI bus registry to find the first available SPI bus.
b, err := spireg.Open("")
if err != nil {
	log.Fatal(err)
}
defer b.Close()

dev, err := epd.NewSPIHat(b, &epd.EPD2in13) // Display config and size
if err != nil {
	log.Fatalf("failed to initialize epd: %v", err)
}

var img image.Image
// Note: this code is commented out so periph does not depend on:
//    "github.com/fogleman/gg"
//    "github.com/golang/freetype/truetype"
//    "golang.org/x/image/font/gofont/goregular"
//
// bounds := dev.Bounds()
// w := bounds.Dx()
// h := bounds.Dy()
// dc := gg.NewContext(w, h)
// im, err := gg.LoadPNG("gopher.png")
// if err != nil {
// 	panic(err)
// }
// dc.SetRGB(1, 1, 1)
// dc.Clear()
// dc.SetRGB(0, 0, 0)
// dc.Rotate(gg.Radians(90))
// dc.Translate(0.0, -float64(h/2))
// font, err := truetype.Parse(goregular.TTF)
// if err != nil {
// 	panic(err)
// }
// face := truetype.NewFace(font, &truetype.Options{
// 	Size: 16,
// })
// dc.SetFontFace(face)
// text := "Hello from periph!"
// tw, th := dc.MeasureString(text)
// dc.DrawImage(im, 120, 30)
// padding := 8.0
// dc.DrawRoundedRectangle(padding*2, padding*2, tw+padding*2, th+padding, 10)
// dc.Stroke()
// dc.DrawString(text, padding*3, padding*2+th)
// for i := 0; i < 10; i++ {
// 	dc.DrawCircle(float64(30+(10*i)), 100, 5)
// }
// for i := 0; i < 10; i++ {
// 	dc.DrawRectangle(float64(30+(10*i)), 80, 5, 5)
// }
// dc.Fill()
// img = dc.Image()
if err := dev.Draw(dev.Bounds(), img, image.Point{}); err != nil {
	log.Fatal(err)
}
dev.DisplayFrame() // After drawing on the display, you have to show the frame

Output:

Index

Examples

Constants

This section is empty.

Variables

View Source 
var EPD1in54 = Opts{
	W: 200,
	H: 200,
	FullUpdate: LUT{
		0x02, 0x02, 0x01, 0x11, 0x12, 0x12, 0x22, 0x22,
		0x66, 0x69, 0x69, 0x59, 0x58, 0x99, 0x99, 0x88,
		0x00, 0x00, 0x00, 0x00, 0xF8, 0xB4, 0x13, 0x51,
		0x35, 0x51, 0x51, 0x19, 0x01, 0x00,
	},
	PartialUpdate: LUT{
		0x10, 0x18, 0x18, 0x08, 0x18, 0x18, 0x08, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x13, 0x14, 0x44, 0x12,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	},
}

EPD1in54 is the config for the 1.54 inch display.

View Source 
var EPD2in13 = Opts{
	W: 128,
	H: 250,
	FullUpdate: LUT{
		0x22, 0x55, 0xAA, 0x55, 0xAA, 0x55, 0xAA, 0x11,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x1E, 0x1E, 0x1E, 0x1E, 0x1E, 0x1E, 0x1E, 0x1E,
		0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
	},
	PartialUpdate: LUT{
		0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x0F, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
	},
}

EPD2in13 is the config for the 2.13 inch display.

View Source 
var EPD2in13v2 = Opts{
	W: 128,
	H: 250,
	FullUpdate: LUT{
		0x80, 0x60, 0x40, 0x00, 0x00, 0x00, 0x00,
		0x10, 0x60, 0x20, 0x00, 0x00, 0x00, 0x00,
		0x80, 0x60, 0x40, 0x00, 0x00, 0x00, 0x00,
		0x10, 0x60, 0x20, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

		0x03, 0x03, 0x00, 0x00, 0x02,
		0x09, 0x09, 0x00, 0x00, 0x02,
		0x03, 0x03, 0x00, 0x00, 0x02,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,

		0x15, 0x41, 0xA8, 0x32, 0x30, 0x0A,
	},
	PartialUpdate: LUT{
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,

		0x0A, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,
		0x00, 0x00, 0x00, 0x00, 0x00,

		0x15, 0x41, 0xA8, 0x32, 0x30, 0x0A,
	},
}

EPD2in13v2 is the config for the 2.13 inch v2 display.

Functions

This section is empty.

Types

type Dev 

type Dev struct {
	// contains filtered or unexported fields
}

Dev is an open handle to the display controller.

func NewSPI 

func NewSPI(p spi.Port, dc, cs, rst gpio.PinOut, busy gpio.PinIO, opts *Opts) (*Dev, error)

NewSPI returns a Dev object that communicates over SPI to a E-Paper display controller.

func NewSPIHat 

func NewSPIHat(p spi.Port, opts *Opts) (*Dev, error)

NewSPIHat returns a Dev object that communicates over SPI and have the default config for the e-paper hat for raspberry pi

func (*Dev) Bounds 

func (d *Dev) Bounds() image.Rectangle

Bounds implements display.Drawer. Min is guaranteed to be {0, 0}.

func (*Dev) ClearFrameMemory 

func (d *Dev) ClearFrameMemory(color byte) error

ClearFrameMemory clear the frame memory with the specified color. this won't update the display.

func (*Dev) ColorModel 

func (d *Dev) ColorModel() color.Model

ColorModel implements display.Drawer. It is a one bit color model, as implemented by image1bit.Bit.

func (*Dev) DisplayFrame 

func (d *Dev) DisplayFrame() error

DisplayFrame update the display.

There are 2 memory areas embedded in the e-paper display but once this function is called, the next action of SetFrameMemory or ClearFrame will set the other memory area.

func (*Dev) Draw 

func (d *Dev) Draw(r image.Rectangle, src image.Image, sp image.Point) error

Draw implements display.Drawer.

func (*Dev) Halt 

func (d *Dev) Halt() error

Halt turns off the display.

func (*Dev) Init 

func (d *Dev) Init() error

Init initialize the display config. This method is already called when creating a device using NewSPI and NewSPIHat methods.

It should be only used when you put the device to sleep and need to re-init the device.

func (*Dev) Reset 

func (d *Dev) Reset()

Reset can be also used to awaken the device

func (*Dev) Sleep 

func (d *Dev) Sleep() error

Sleep after this command is transmitted, the chip would enter the deep-sleep mode to save power.

The deep sleep mode would return to standby by hardware reset. You can use Reset() to awaken and Init to re-initialize the device.

func (*Dev) String 

func (d *Dev) String() string

type LUT 

type LUT []byte

LUT contains the display specific waveform for the pixel programming of the display.

type Opts 

type Opts struct {
	W             int
	H             int
	FullUpdate    LUT
	PartialUpdate LUT
}

Opts defines the options for the ePaper Device.

type PartialUpdate 

type PartialUpdate bool

PartialUpdate represents if updates to the display should be full or partial. 

const (
	// Full LUT config to update all the display
	Full PartialUpdate = false
	// Partial LUT config only a part of the display
	Partial PartialUpdate = true
)

Source Files

View all Source files

Directories

Path Synopsis
Package image2bit implements two bit gray scale (white, light gray, dark gray, black) 2D graphics.
 Package image2bit implements two bit gray scale (white, light gray, dark gray, black) 2D graphics.

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