inky

Documentation

Overview

Package inky drives an Inky pHAT, pHAT v2 or wHAT E ink display.

Datasheet

Inky lacks a true datasheet, so the code here is derived from the reference implementation by Pimoroni: https://github.com/pimoroni/inky

The display seems to use a SSD1675 controller: https://www.china-epaper.com/uploads/soft/DEPG0420R01V3.0.pdf

Example

path := flag.String("image", "", "Path to image file (212x104) to display")
flag.Parse()

f, err := os.Open(*path)
if err != nil {
	log.Fatal(err)
}
defer f.Close()

img, err := png.Decode(f)
if err != nil {
	log.Fatal(err)
}

if _, err = host.Init(); err != nil {
	log.Fatal(err)
}

b, err := spireg.Open("SPI0.0")
if err != nil {
	log.Fatal(err)
}

dc := gpioreg.ByName("22")
reset := gpioreg.ByName("27")
busy := gpioreg.ByName("17")

dev, err := inky.New(b, dc, reset, busy, &inky.Opts{
	Model:       inky.PHAT,
	ModelColor:  inky.Red,
	BorderColor: inky.Black,
})
if err != nil {
	log.Fatal(err)
}

if err := dev.Draw(img.Bounds(), img, image.Point{}); err != nil {
	log.Fatal(err)
}

Index

• type Color
  • func (c *Color) Set(s string) error
  • func (c *Color) String() string
• type Dev
  • func New(p spi.Port, dc gpio.PinOut, reset gpio.PinOut, busy gpio.PinIn, o *Opts) (*Dev, error)
  • func (d *Dev) Bounds() image.Rectangle
  • func (d *Dev) ColorModel() color.Model
  • func (d *Dev) Draw(dstRect image.Rectangle, src image.Image, srcPtrs image.Point) error
  • func (d *Dev) DrawAll(src image.Image) error
  • func (d *Dev) Halt() error
  • func (d *Dev) SetBorder(c Color)
  • func (d *Dev) SetModelColor(c Color) error
  • func (d *Dev) String() string
• type Model
  • func (m *Model) Set(s string) error
  • func (m *Model) String() string
• type Opts
  • func DetectOpts(bus i2c.Bus) (*Opts, error)

Examples

• Package

Types

type Color

type Color int

Color is used to define which model of inky is being used, and also for setting the border color.

const (
	Black Color = iota
	Red
	Yellow
	White
)

Valid Color.

func (*Color) Set

func (c *Color) Set(s string) error

Set sets the Color to a value represented by the string s. Set implements the flag.Value interface.

func (*Color) String

func (c *Color) String() string

type Dev

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

Dev is a handle to an Inky.

func New

func New(p spi.Port, dc gpio.PinOut, reset gpio.PinOut, busy gpio.PinIn, o *Opts) (*Dev, error)

New opens a handle to an Inky pHAT or wHAT.

func (*Dev) Bounds

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

Bounds implements display.Drawer

func (*Dev) ColorModel

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

ColorModel implements display.Drawer Maps white to white, black to black and anything else as red. Red is used as a placeholder for the display's third color, i.e., red or yellow.

func (*Dev) Draw

func (d *Dev) Draw(dstRect image.Rectangle, src image.Image, srcPtrs image.Point) error

Draw implements display.Drawer

func (*Dev) DrawAll

func (d *Dev) DrawAll(src image.Image) error

DrawAll redraws the whole display.

func (*Dev) Halt

func (d *Dev) Halt() error

Halt implements conn.Resource

func (*Dev) SetBorder

func (d *Dev) SetBorder(c Color)

SetBorder changes the border color. This will not take effect until the next Draw().

func (*Dev) SetModelColor

func (d *Dev) SetModelColor(c Color) error

SetModelColor changes the model color. This will not take effect until the next Draw(). Useful if you want to switch between two-color and three-color drawing.

func (*Dev) String

func (d *Dev) String() string

String implements conn.Resource.

type Model

type Model int

Model lists the supported e-ink display models.

const (
	PHAT Model = iota
	WHAT
	PHAT2
)

Supported Model.

func (*Model) Set

func (m *Model) Set(s string) error

Set sets the Model to a value represented by the string s. Set implements the flag.Value interface.

func (*Model) String

func (m *Model) String() string

type Opts

type Opts struct {
	// Model being used.
	Model Model
	// Model color.
	ModelColor Color
	// Initial border color. Will be set on the first Draw().
	BorderColor Color
}

Opts is the options to specify which device is being controlled and its default settings.

func DetectOpts

func DetectOpts(bus i2c.Bus) (*Opts, error)

DetectOpts tries to read the device opts from EEPROM.