support flashing pca10059 from windows

builder/build.go

@@ -639,6 +639,18 @@ func Build(pkgName, outpath string, config *compileopts.Config, action func(Buil
 		if err != nil {
 			return err
 		}
+	case "nrf-dfu":
+		// special format for nrfutil for Nordic chips
+		tmphexpath := filepath.Join(dir, "main.hex")
+		err := objcopy(executable, tmphexpath, "hex")
+		if err != nil {
+			return err
+		}
+		tmppath = filepath.Join(dir, "main"+outext)
+		err = makeDFUFirmwareImage(config.Options, tmphexpath, tmppath)
+		if err != nil {
+			return err
+		}
 	default:
 		return fmt.Errorf("unknown output binary format: %s", outputBinaryFormat)
 	}

builder/nrfutil.go

@@ -0,0 +1,27 @@
+package builder
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os/exec"
+
+	"github.com/tinygo-org/tinygo/compileopts"
+)
+
+// https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_nrfutil%2FUG%2Fnrfutil%2Fnrfutil_intro.html
+
+func makeDFUFirmwareImage(options *compileopts.Options, infile, outfile string) error {
+	cmdLine := []string{"nrfutil", "pkg", "generate", "--hw-version", "52", "--sd-req", "0x0", "--debug-mode", "--application", infile, outfile}
+
+	if options.PrintCommands != nil {
+		options.PrintCommands(cmdLine[0], cmdLine[1:]...)
+	}
+
+	cmd := exec.Command(cmdLine[0], cmdLine[1:]...)
+	cmd.Stdout = ioutil.Discard
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("could not run nrfutil pkg generate: %w", err)
+	}
+	return nil
+}