Remarks

St7735
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

The ST7735 is a display controller used to drive color displays over SPI using 12, 16 or 18 bbp. These displays require a backlight. These displays are commonly found with a resolution of 128x160.

The Meadow.Foundation ST7735 driver currently only supports 16bpp RGB565.

Code Example

MicroGraphics graphics;

public override Task Initialize()
{
    Resolver.Log.Info("Initializing ...");

    var spiBus = Device.CreateSpiBus(St7735.DefaultSpiBusSpeed);

    //note - you may need to adjust the DisplayType for your specific St7735
    var display = new St7735(
        spiBus: spiBus,
        chipSelectPin: Device.Pins.D02,
        dcPin: Device.Pins.D01,
        resetPin: Device.Pins.D00,
        width: 128,
        height: 160,
        St7735.DisplayType.ST7735R);

    graphics = new MicroGraphics(display);

    return base.Initialize();
}

public override Task Run()
{
    graphics.Clear();

    graphics.DrawCircle(60, 60, 20, Color.Purple);
    graphics.DrawRectangle(10, 10, 30, 60, Color.Red);
    graphics.DrawTriangle(20, 20, 10, 70, 60, 60, Color.Green);

    graphics.DrawCircle(90, 60, 20, Color.Cyan, true);
    graphics.DrawRectangle(100, 100, 30, 10, Color.Yellow, true);
    graphics.DrawTriangle(120, 20, 110, 70, 160, 60, Color.Pink, true);

    graphics.DrawLine(10, 120, 110, 130, Color.SlateGray);

    graphics.Show();

    return base.Run();
}

Sample project(s) available on GitHub

Wiring Example

To wire a ST7735 to your Meadow board, connect the following:

ST7735	Meadow Pin
LED-	3V3
LED+	GND
MOSI	MOSI
SCK	SCK
RESET	D15
A0	D14
CS	D13
VCC	3V3
GND	GND

It should look like the following diagram:

Characteristic	Locus
Inheritance	System.Object TftSpiBase > St7735
Implements	IGraphicsDisplay
Inherited Members	TftSpiBase.ColorMode TftSpiBase.Rotation TftSpiBase.Width TftSpiBase.Height TftSpiBase.PixelBuffer TftSpiBase.dataCommandPort TftSpiBase.resetPort TftSpiBase.chipSelectPort TftSpiBase.spiDisplay TftSpiBase.imageBuffer TftSpiBase.readBuffer TftSpiBase.Data TftSpiBase.Command TftSpiBase.IsColorTypeSupported(ColorMode) TftSpiBase.CreateBuffer(ColorMode, Int32, Int32) TftSpiBase.Clear(Boolean) TftSpiBase.Fill(Color, Boolean) TftSpiBase.WriteBuffer(Int32, Int32, IPixelBuffer) TftSpiBase.DrawPixel(Int32, Int32, Boolean) TftSpiBase.DrawPixel(Int32, Int32, Color) TftSpiBase.DrawPixel(Int32, Int32, Byte, Byte, Byte) TftSpiBase.InvertPixel(Int32, Int32) TftSpiBase.Fill(Int32, Int32, Int32, Int32, Color) TftSpiBase.Show() TftSpiBase.Show(Int32, Int32, Int32, Int32) TftSpiBase.Write(Byte) TftSpiBase.Write(Byte[]) TftSpiBase.DelayMs(Int32) TftSpiBase.SendCommand(TftSpiBase.Register) TftSpiBase.SendCommand(TftSpiBase.LcdCommand) TftSpiBase.SendCommand(Byte) TftSpiBase.SendData(Int32) TftSpiBase.SendData(Byte) TftSpiBase.SendData(Byte[]) TftSpiBase.Clear(Color)
Namespace	Meadow.Foundation.Displays
Assembly	TftSpi.dll

Syntax

public class St7735 : TftSpiBase, IGraphicsDisplay

Constructors

St7735(ISpiBus, IDigitalOutputPort, IDigitalOutputPort, IDigitalOutputPort, Int32, Int32, St7735.DisplayType, ColorMode)

Create a new St7735 color display object

Declaration

public St7735(ISpiBus spiBus, IDigitalOutputPort chipSelectPort, IDigitalOutputPort dataCommandPort, IDigitalOutputPort resetPort, int width, int height, St7735.DisplayType displayType = St7735.DisplayType.ST7735R, ColorMode colorMode = default(ColorMode))

Parameters

Type	Name	Description
ISpiBus	spiBus	SPI bus connected to display
IDigitalOutputPort	chipSelectPort	Chip select output port
IDigitalOutputPort	dataCommandPort	Data command output port
IDigitalOutputPort	resetPort	Reset output port
System.Int32	width	Width of display in pixels
System.Int32	height	Height of display in pixels
St7735.DisplayType	displayType	The St7735 display types (displays vary from manufacturer and screen size)
ColorMode	colorMode	The color mode to use for the display buffer

St7735(ISpiBus, IPin, IPin, IPin, Int32, Int32, St7735.DisplayType, ColorMode)

Create a new St7735 color display object

Declaration

public St7735(ISpiBus spiBus, IPin chipSelectPin, IPin dcPin, IPin resetPin, int width, int height, St7735.DisplayType displayType = St7735.DisplayType.ST7735R, ColorMode colorMode = default(ColorMode))

Parameters

Type	Name	Description
ISpiBus	spiBus	SPI bus connected to display
IPin	chipSelectPin	Chip select pin
IPin	dcPin	Data command pin
IPin	resetPin	Reset pin
System.Int32	width	Width of display in pixels
System.Int32	height	Height of display in pixels
St7735.DisplayType	displayType	The St7735 display types (displays vary from manufacturer and screen size)
ColorMode	colorMode	The color mode to use for the display buffer

Fields

DefaultSpiBusSpeed

The default SPI bus frequency

Declaration

public static Frequency DefaultSpiBusSpeed

Field Value

Type	Description
Frequency

Properties

DefautColorMode

The default display color mode

Declaration

public override ColorMode DefautColorMode { get; }

Property Value

Type	Description
ColorMode

Overrides

TftSpiBase.DefautColorMode

SupportedColorModes

The color modes supported by the display

Declaration

public override ColorMode SupportedColorModes { get; }

Property Value

Type	Description
ColorMode

Overrides

TftSpiBase.SupportedColorModes

Methods

Initialize()

Initalize the display

Declaration

protected override void Initialize()

Overrides

TftSpiBase.Initialize()

SetAddressWindow(Int32, Int32, Int32, Int32)

Set addrees window for display updates

Declaration

protected override void SetAddressWindow(int x0, int y0, int x1, int y1)

Parameters

Type	Name	Description
System.Int32	x0	X start in pixels
System.Int32	y0	Y start in pixels
System.Int32	x1	X end in pixels
System.Int32	y1	Y end in pixels

Overrides

TftSpiBase.SetAddressWindow(Int32, Int32, Int32, Int32)