feat: add Ground Station UART baseline

2026-09-29 11:25:59 +02:00
commit 515c3bae69
7 changed files with 279 additions and 0 deletions
@@ -0,0 +1,90 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"os/signal"
+	"syscall"
+
+	"git.piksar.eu/piotr/groundstation/internal/protocol"
+	"git.piksar.eu/piotr/groundstation/internal/serialport"
+)
+
+func main() {
+	serialPath := flag.String("serial", "", "GX12 AUX1 UART device, e.g. /dev/ttyS1")
+	stdin := flag.Bool("stdin", false, "read framed data from standard input")
+	startVideo := flag.Bool("start-video", false, "start fpv-video with Ground Station")
+	flag.Parse()
+
+	if *stdin == (*serialPath != "") {
+		log.Fatal("select exactly one of -stdin or -serial")
+	}
+
+	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
+	defer stop()
+
+	if *startVideo {
+		cmd := exec.CommandContext(ctx, "fpv-video")
+		cmd.Stdout, cmd.Stderr = os.Stdout, os.Stderr
+		if err := cmd.Start(); err != nil {
+			log.Fatalf("start fpv-video: %v", err)
+		}
+		defer func() { _ = cmd.Wait() }()
+	}
+
+	var input io.Reader = os.Stdin
+	var port *os.File
+	var err error
+	if *serialPath != "" {
+		port, err = serialport.Open115200(*serialPath)
+		if err != nil {
+			log.Fatal(err)
+		}
+		defer port.Close()
+		input = port
+	}
+
+	if err := run(ctx, input, os.Stdout); err != nil && err != context.Canceled {
+		log.Fatal(err)
+	}
+}
+
+func run(ctx context.Context, input io.Reader, output io.Writer) error {
+	buf := make([]byte, protocol.RCSize)
+	for {
+		if err := readFull(ctx, input, buf); err != nil {
+			return err
+		}
+		frame, err := protocol.DecodeRC(buf)
+		if err != nil {
+			log.Printf("discard frame: %v", err)
+			continue
+		}
+		fmt.Fprintf(output, "seq=%d t=%d ch1=%d ch2=%d ch3=%d ch4=%d aux1=%d aux2=%d\n",
+			frame.Sequence, frame.Timestamp,
+			frame.Channels[0], frame.Channels[1], frame.Channels[2], frame.Channels[3],
+			frame.Channels[4], frame.Channels[5])
+	}
+}
+
+func readFull(ctx context.Context, input io.Reader, dst []byte) error {
+	read := 0
+	for read < len(dst) {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+		}
+		n, err := input.Read(dst[read:])
+		read += n
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}