feat: add Ground Station UART baseline

internal/protocol/rc_test.go

@@ -0,0 +1,26 @@
+package protocol
+
+import "testing"
+
+func TestRCFrameRoundTrip(t *testing.T) {
+	input := RCFrame{Sequence: 42, Timestamp: 123456}
+	for i := range input.Channels {
+		input.Channels[i] = int16(i*100 - 750)
+	}
+
+	got, err := DecodeRC(EncodeRC(input))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != input {
+		t.Fatalf("round trip mismatch: got %#v want %#v", got, input)
+	}
+}
+
+func TestRCFrameRejectsBadCRC(t *testing.T) {
+	packet := EncodeRC(RCFrame{})
+	packet[Header] ^= 1
+	if _, err := DecodeRC(packet); err == nil {
+		t.Fatal("expected CRC error")
+	}
+}