commit ae312a04575c5c33a73ef951fca686e91c1ba2c0
Author: Andrey Egorov <and7643@gmail.com>
Date:   Tue Aug 20 15:14:10 2024 +0300

    Initial.

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..b9161d0
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+out/
+go.sum
+.git/
+*.swp
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..ce98226
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,7 @@
+export GOOS=linux
+export GOARCH=arm
+export GOARM=6
+export CGO_ENABLED=0
+
+build:
+	@go build -o out/out main.go
diff --git a/display/display.go b/display/display.go
new file mode 100644
index 0000000..a4208c6
--- /dev/null
+++ b/display/display.go
@@ -0,0 +1,33 @@
+package display
+
+import (
+	"fmt"
+	"image"
+	"io"
+	"log"
+
+	"golang.org/x/image/font"
+)
+
+type Display interface {
+	GetImg() *image.Gray
+	GetFont() font.Face
+	Clear() error
+	PutText(x, y int, text string) error
+
+	io.Closer
+}
+
+type DisplayModel int
+
+const (
+	SSD1306 DisplayModel = iota
+)
+
+func New(logger *log.Logger, model DisplayModel) (Display, error) {
+	switch model {
+	case SSD1306:
+		return newSsd1306(logger)
+	}
+	return nil, fmt.Errorf("invalid display model")
+}
diff --git a/display/ssd1336.go b/display/ssd1336.go
new file mode 100644
index 0000000..fa634b1
--- /dev/null
+++ b/display/ssd1336.go
@@ -0,0 +1,112 @@
+package display
+
+import (
+	"fmt"
+	"image"
+	"image/color"
+	"log"
+	"sync"
+
+	"golang.org/x/image/font"
+	"golang.org/x/image/font/inconsolata"
+	"golang.org/x/image/math/fixed"
+	"periph.io/x/conn/v3/i2c"
+	"periph.io/x/conn/v3/i2c/i2creg"
+	"periph.io/x/devices/v3/ssd1306"
+	"periph.io/x/host/v3"
+)
+
+type displaySsd1306 struct {
+	mutex  sync.Mutex
+	logger *log.Logger
+
+	font font.Face
+	bus  i2c.BusCloser
+	dev  *ssd1306.Dev
+	img  *image.Gray
+}
+
+func newSsd1306(logger *log.Logger) (Display, error) {
+	if _, err := host.Init(); err != nil {
+		return nil, fmt.Errorf("drivers init: %w(may be i2c is disabled)", err)
+	}
+
+	// Setup device
+	bus, err := i2creg.Open("")
+	if err != nil {
+		return nil, fmt.Errorf("open i2c bus: %w", err)
+	}
+	opts := ssd1306.Opts{
+		W:             128,
+		H:             32,
+		Rotated:       false,
+		Sequential:    true,
+		SwapTopBottom: false,
+	}
+	dev, err := ssd1306.NewI2C(bus, &opts)
+	if err != nil {
+		return nil, fmt.Errorf("create i2c: %w", err)
+	}
+
+	// Create image
+	img := image.NewGray(image.Rect(0, 0, dev.Bounds().Dx(), dev.Bounds().Dy()))
+
+	return &displaySsd1306{
+		logger: logger,
+		font:   inconsolata.Regular8x16,
+		bus:    bus,
+		dev:    dev,
+		img:    img,
+	}, nil
+}
+
+func (d *displaySsd1306) GetImg() *image.Gray {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+
+	return d.img
+}
+
+func (d *displaySsd1306) GetFont() font.Face {
+	return d.font
+}
+
+func (d *displaySsd1306) Clear() error {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+
+	for i := range d.img.Pix {
+		d.img.Pix[i] = 0
+	}
+	return nil
+}
+
+func (d *displaySsd1306) PutText(x, y int, text string) error {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+
+	// Create font drawer
+	col := color.Gray{255}
+	point := fixed.Point26_6{X: fixed.I(x), Y: fixed.I(y)}
+
+	drawer := &font.Drawer{
+		Dst:  d.img,
+		Src:  image.NewUniform(col),
+		Face: d.font,
+		Dot:  point,
+	}
+	drawer.DrawString(text)
+
+	d.dev.Draw(d.img.Bounds(), d.img, image.Point{})
+	return nil
+}
+
+func (d *displaySsd1306) Close() error {
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+
+	if err := d.bus.Close(); err != nil {
+		d.logger.Println("Close i2c bus:", err.Error())
+	}
+	return nil
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..72fbdbe
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,10 @@
+module display-test
+
+go 1.22.5
+
+require (
+	golang.org/x/image v0.1.0
+	periph.io/x/conn/v3 v3.7.1
+	periph.io/x/devices/v3 v3.7.1
+	periph.io/x/host/v3 v3.8.2
+)
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..8e22679
--- /dev/null
+++ b/main.go
@@ -0,0 +1,30 @@
+package main
+
+import (
+	"display-test/display"
+	"fmt"
+	"log"
+)
+
+func main() {
+	log.Println("CGSG forever!!!")
+
+	if err := mainE(); err != nil {
+		log.Println("MAIN finished with error:", err.Error())
+	}
+	log.Println("END")
+}
+
+func mainE() error {
+	d, err := display.New(log.New(log.Writer(), "display", log.LstdFlags), display.SSD1306)
+	if err != nil {
+		return fmt.Errorf("new display: %w", err)
+	}
+	defer d.Close()
+
+	for {
+		d.Clear()
+		d.PutText(0, d.GetFont().Metrics().Height.Ceil(), "Satelites: 0")
+		d.PutText(0, d.GetFont().Metrics().Height.Ceil()*2, "Coords: 0N 0E")
+	}
+}