SSD1331 TFT color display (#77)

Makefile

@@ -37,6 +37,7 @@ smoke-test:
 	tinygo build -size short -o ./build/test.elf -target=microbit ./examples/sht3x/main.go
 	tinygo build -size short -o ./build/test.elf -target=microbit ./examples/ssd1306/i2c_128x32/main.go
 	tinygo build -size short -o ./build/test.elf -target=microbit ./examples/ssd1306/spi_128x64/main.go
+	tinygo build -size short -o ./build/test.elf -target=microbit ./examples/ssd1331/main.go
 	tinygo build -size short -o ./build/test.elf -target=microbit ./examples/st7735/main.go
 	tinygo build -size short -o ./build/test.elf -target=microbit ./examples/st7789/main.go
 	tinygo build -size short -o ./build/test.elf -target=circuitplay-express ./examples/thermistor/main.go

README.md

@@ -77,6 +77,7 @@ func main() {
 | [PCD8544 display](http://eia.udg.edu/~forest/PCD8544_1.pdf) | SPI |
 | [SHT3x Digital Humidity Sensor](https://www.sensirion.com/fileadmin/user_upload/customers/sensirion/Dokumente/0_Datasheets/Humidity/Sensirion_Humidity_Sensors_SHT3x_Datasheet_digital.pdf) | I2C |
 | [SSD1306 OLED display](https://cdn-shop.adafruit.com/datasheets/SSD1306.pdf) | I2C / SPI |
+| [SSD1331 TFT color display](https://www.crystalfontz.com/controllers/SolomonSystech/SSD1331/381/) | SPI |
 | [ST7735 TFT color display](https://www.crystalfontz.com/controllers/Sitronix/ST7735R/319/) | SPI |
 | [ST7789 TFT color display](https://cdn-shop.adafruit.com/product-files/3787/3787_tft_QT154H2201__________20190228182902.pdf) | SPI |
 | [Thermistor](https://www.farnell.com/datasheets/33552.pdf) | ADC |

examples/ssd1331/main.go

@@ -0,0 +1,33 @@
+package ssd1331
+
+import (
+	"machine"
+
+	"image/color"
+
+	"tinygo.org/x/drivers/ssd1331"
+)
+
+func main() {
+	machine.SPI0.Configure(machine.SPIConfig{
+		Frequency: 8000000,
+	})
+	display := ssd1331.New(machine.SPI0, machine.P6, machine.P7, machine.P8)
+	display.Configure(ssd1331.Config{})
+	display.SetContrast(0x30, 0x20, 0x30)
+	width, height := display.Size()
+
+	white := color.RGBA{255, 255, 255, 255}
+	red := color.RGBA{255, 0, 0, 255}
+	blue := color.RGBA{0, 0, 255, 255}
+	green := color.RGBA{0, 255, 0, 255}
+	black := color.RGBA{0, 0, 0, 255}
+
+	display.FillScreen(black)
+
+	display.FillRectangle(0, 0, width/2, height/2, white)
+	display.FillRectangle(width/2, 0, width/2, height/2, red)
+	display.FillRectangle(0, height/2, width/2, height/2, green)
+	display.FillRectangle(width/2, height/2, width/2, height/2, blue)
+	display.FillRectangle(width/4, height/4, width/2, height/2, black)
+}

ssd1331/registers.go

@@ -0,0 +1,33 @@
+package ssd1331
+
+// Registers
+const (
+	DRAWLINE       = 0x21
+	DRAWRECT       = 0x22
+	FILL           = 0x26
+	SETCOLUMN      = 0x15
+	SETROW         = 0x75
+	CONTRASTA      = 0x81
+	CONTRASTB      = 0x82
+	CONTRASTC      = 0x83
+	MASTERCURRENT  = 0x87
+	SETREMAP       = 0xA0
+	STARTLINE      = 0xA1
+	DISPLAYOFFSET  = 0xA2
+	NORMALDISPLAY  = 0xA4
+	DISPLAYALLON   = 0xA5
+	DISPLAYALLOFF  = 0xA6
+	INVERTDISPLAY  = 0xA7
+	SETMULTIPLEX   = 0xA8
+	SETMASTER      = 0xAD
+	DISPLAYOFF     = 0xAE
+	DISPLAYON      = 0xAF
+	POWERMODE      = 0xB0
+	PRECHARGE      = 0xB1
+	CLOCKDIV       = 0xB3
+	PRECHARGEA     = 0x8A
+	PRECHARGEB     = 0x8B
+	PRECHARGEC     = 0x8C
+	PRECHARGELEVEL = 0xBB
+	VCOMH          = 0xBE
+)

ssd1331/ssd1331.go

@@ -0,0 +1,286 @@
+// Package ssd1331 implements a driver for the SSD1331 TFT color displays.
+//
+// Datasheet: https://www.crystalfontz.com/controllers/SolomonSystech/SSD1331/381/
+//
+package ssd1331 // import "tinygo.org/x/drivers/ssd1331"
+
+import (
+	"image/color"
+	"machine"
+
+	"errors"
+	"time"
+)
+
+type Model uint8
+type Rotation uint8
+
+// Device wraps an SPI connection.
+type Device struct {
+	bus         machine.SPI
+	dcPin       machine.Pin
+	resetPin    machine.Pin
+	csPin       machine.Pin
+	width       int16
+	height      int16
+	batchLength int16
+	isBGR       bool
+	batchData   []uint8
+}
+
+// Config is the configuration for the display
+type Config struct {
+	Width  int16
+	Height int16
+}
+
+// New creates a new ST7735 connection. The SPI wire must already be configured.
+func New(bus machine.SPI, resetPin, dcPin, csPin machine.Pin) Device {
+	dcPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
+	resetPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
+	csPin.Configure(machine.PinConfig{Mode: machine.PinOutput})
+	return Device{
+		bus:      bus,
+		dcPin:    dcPin,
+		resetPin: resetPin,
+		csPin:    csPin,
+	}
+}
+
+// Configure initializes the display with default configuration
+func (d *Device) Configure(cfg Config) {
+	if cfg.Width != 0 {
+		d.width = cfg.Width
+	} else {
+		d.width = 96
+	}
+	if cfg.Height != 0 {
+		d.height = cfg.Height
+	} else {
+		d.height = 64
+	}
+
+	d.batchLength = d.width
+	if d.height > d.width {
+		d.batchLength = d.height
+	}
+	d.batchLength += d.batchLength & 1
+	d.batchData = make([]uint8, d.batchLength*2)
+
+	// reset the device
+	d.resetPin.High()
+	time.Sleep(100 * time.Millisecond)
+	d.resetPin.Low()
+	time.Sleep(100 * time.Millisecond)
+	d.resetPin.High()
+	time.Sleep(200 * time.Millisecond)
+
+	// Initialization
+	d.Command(DISPLAYOFF)
+	d.Command(SETREMAP)
+	d.Command(0x72) // RGB
+	//d.Command(0x76) // BGR
+	d.Command(STARTLINE)
+	d.Command(0x0)
+	d.Command(DISPLAYOFFSET)
+	d.Command(0x0)
+	d.Command(NORMALDISPLAY)
+	d.Command(SETMULTIPLEX)
+	d.Command(0x3F)
+	d.Command(SETMASTER)
+	d.Command(0x8E)
+	d.Command(POWERMODE)
+	d.Command(0x0B)
+	d.Command(PRECHARGE)
+	d.Command(0x31)
+	d.Command(CLOCKDIV)
+	d.Command(0xF0)
+	d.Command(PRECHARGEA)
+	d.Command(0x64)
+	d.Command(PRECHARGEB)
+	d.Command(0x78)
+	d.Command(PRECHARGEC)
+	d.Command(0x64)
+	d.Command(PRECHARGELEVEL)
+	d.Command(0x3A)
+	d.Command(VCOMH)
+	d.Command(0x3E)
+	d.Command(MASTERCURRENT)
+	d.Command(0x06)
+	d.Command(CONTRASTA)
+	d.Command(0x91)
+	d.Command(CONTRASTB)
+	d.Command(0x50)
+	d.Command(CONTRASTC)
+	d.Command(0x7D)
+	d.Command(DISPLAYON)
+}
+
+// Display does nothing, there's no buffer as it might be too big for some boards
+func (d *Device) Display() error {
+	return nil
+}
+
+// SetPixel sets a pixel in the screen
+func (d *Device) SetPixel(x int16, y int16, c color.RGBA) {
+	if x < 0 || y < 0 || x >= d.width || y >= d.height {
+		return
+	}
+	d.FillRectangle(x, y, 1, 1, c)
+}
+
+// setWindow prepares the screen to be modified at a given rectangle
+func (d *Device) setWindow(x, y, w, h int16) {
+	/*d.Tx([]uint8{SETCOLUMN}, true)
+	d.Tx([]uint8{uint8(x), uint8(x + w - 1)}, false)
+	d.Tx([]uint8{SETROW}, true)
+	d.Tx([]uint8{uint8(y), uint8(y + h - 1)}, false)*/
+	d.Command(SETCOLUMN)
+	d.Command(uint8(x))
+	d.Command(uint8(x + w - 1))
+	d.Command(SETROW)
+	d.Command(uint8(y))
+	d.Command(uint8(y + h - 1))
+}
+
+// FillRectangle fills a rectangle at a given coordinates with a color
+func (d *Device) FillRectangle(x, y, width, height int16, c color.RGBA) error {
+	if x < 0 || y < 0 || width <= 0 || height <= 0 ||
+		x >= d.width || (x+width) > d.width || y >= d.height || (y+height) > d.height {
+		return errors.New("rectangle coordinates outside display area")
+	}
+	d.setWindow(x, y, width, height)
+	c565 := RGBATo565(c)
+	c1 := uint8(c565 >> 8)
+	c2 := uint8(c565)
+
+	var i int16
+	for i = 0; i < d.batchLength; i++ {
+		d.batchData[i*2] = c1
+		d.batchData[i*2+1] = c2
+	}
+	i = width * height
+	for i > 0 {
+		if i >= d.batchLength {
+			d.Tx(d.batchData, false)
+		} else {
+			d.Tx(d.batchData[:i*2], false)
+		}
+		i -= d.batchLength
+	}
+	return nil
+}
+
+// FillRectangle fills a rectangle at a given coordinates with a buffer
+func (d *Device) FillRectangleWithBuffer(x, y, width, height int16, buffer []color.RGBA) error {
+	if x < 0 || y < 0 || width <= 0 || height <= 0 ||
+		x >= d.width || (x+width) > d.width || y >= d.height || (y+height) > d.height {
+		return errors.New("rectangle coordinates outside display area")
+	}
+	k := width * height
+	l := int16(len(buffer))
+	if k != l {
+		return errors.New("buffer length does not match with rectangle size")
+	}
+
+	d.setWindow(x, y, width, height)
+
+	offset := int16(0)
+	for k > 0 {
+		for i := int16(0); i < d.batchLength; i++ {
+			if offset+i < l {
+				c565 := RGBATo565(buffer[offset+i])
+				c1 := uint8(c565 >> 8)
+				c2 := uint8(c565)
+				d.batchData[i*2] = c1
+				d.batchData[i*2+1] = c2
+			}
+		}
+		if k >= d.batchLength {
+			d.Tx(d.batchData, false)
+		} else {
+			d.Tx(d.batchData[:k*2], false)
+		}
+		k -= d.batchLength
+		offset += d.batchLength
+	}
+	return nil
+}
+
+// DrawFastVLine draws a vertical line faster than using SetPixel
+func (d *Device) DrawFastVLine(x, y0, y1 int16, c color.RGBA) {
+	if y0 > y1 {
+		y0, y1 = y1, y0
+	}
+	d.FillRectangle(x, y0, 1, y1-y0+1, c)
+}
+
+// DrawFastHLine draws a horizontal line faster than using SetPixel
+func (d *Device) DrawFastHLine(x0, x1, y int16, c color.RGBA) {
+	if x0 > x1 {
+		x0, x1 = x1, x0
+	}
+	d.FillRectangle(x0, y, x1-x0+1, y, c)
+}
+
+// FillScreen fills the screen with a given color
+func (d *Device) FillScreen(c color.RGBA) {
+	d.FillRectangle(0, 0, d.width, d.height, c)
+}
+
+// SetContrast sets the three contrast values (A, B & C)
+func (d *Device) SetContrast(contrastA, contrastB, contrastC uint8) {
+	d.Command(CONTRASTA)
+	d.Command(contrastA)
+	d.Command(CONTRASTB)
+	d.Command(contrastB)
+	d.Command(CONTRASTC)
+	d.Command(contrastC)
+}
+
+// Command sends a command to the display
+func (d *Device) Command(command uint8) {
+	d.Tx([]byte{command}, true)
+}
+
+// Command sends a data to the display
+func (d *Device) Data(data uint8) {
+	d.Tx([]byte{data}, false)
+}
+
+// Tx sends data to the display
+func (d *Device) Tx(data []byte, isCommand bool) {
+	if isCommand {
+		d.csPin.High()
+		d.dcPin.Low()
+		d.csPin.Low()
+
+		d.bus.Tx(data, nil)
+		d.csPin.High()
+	} else {
+		d.csPin.High()
+		d.dcPin.High()
+		d.csPin.Low()
+
+		d.bus.Tx(data, nil)
+		d.csPin.High()
+	}
+}
+
+// Size returns the current size of the display.
+func (d *Device) Size() (w, h int16) {
+	return d.width, d.height
+}
+
+// IsBGR changes the color mode (RGB/BGR)
+func (d *Device) IsBGR(bgr bool) {
+	d.isBGR = bgr
+}
+
+// RGBATo565 converts a color.RGBA to uint16 used in the display
+func RGBATo565(c color.RGBA) uint16 {
+	r, g, b, _ := c.RGBA()
+	return uint16((r & 0xF800) +
+		((g & 0xFC00) >> 5) +
+		((b & 0xF800) >> 11))
+}