diff --git a/machine/_usb/adc/doc.go b/machine/usb/adc/doc.go
similarity index 100%
rename from machine/_usb/adc/doc.go
rename to machine/usb/adc/doc.go
diff --git a/machine/_usb/adc/midi/buffer.go b/machine/usb/adc/midi/buffer.go
similarity index 96%
rename from machine/_usb/adc/midi/buffer.go
rename to machine/usb/adc/midi/buffer.go
index 39cab2c..28defd7 100644
--- a/machine/_usb/adc/midi/buffer.go
+++ b/machine/usb/adc/midi/buffer.go
@@ -1,7 +1,7 @@
 package midi
 
 import (
-	"runtime/volatile"
+	"github.com/goplus/emb/runtime/volatile"
 )
 
 const bufferSize = 128
diff --git a/machine/_usb/adc/midi/messages.go b/machine/usb/adc/midi/messages.go
similarity index 100%
rename from machine/_usb/adc/midi/messages.go
rename to machine/usb/adc/midi/messages.go
diff --git a/machine/_usb/adc/midi/midi.go b/machine/usb/adc/midi/midi.go
similarity index 94%
rename from machine/_usb/adc/midi/midi.go
rename to machine/usb/adc/midi/midi.go
index 8ead2e9..c6a3eaa 100644
--- a/machine/_usb/adc/midi/midi.go
+++ b/machine/usb/adc/midi/midi.go
@@ -1,9 +1,9 @@
 package midi
 
 import (
-	"machine"
-	"machine/usb"
-	"machine/usb/descriptor"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/machine/usb/descriptor"
 )
 
 const (
diff --git a/machine/_usb/adc/midi/notes.go b/machine/usb/adc/midi/notes.go
similarity index 100%
rename from machine/_usb/adc/midi/notes.go
rename to machine/usb/adc/midi/notes.go
diff --git a/machine/_usb/cdc/buffer.go b/machine/usb/cdc/buffer.go
similarity index 98%
rename from machine/_usb/cdc/buffer.go
rename to machine/usb/cdc/buffer.go
index ad5eb36..f9d7d90 100644
--- a/machine/_usb/cdc/buffer.go
+++ b/machine/usb/cdc/buffer.go
@@ -1,7 +1,7 @@
 package cdc
 
 import (
-	"runtime/volatile"
+	"github.com/goplus/emb/runtime/volatile"
 )
 
 const rxRingBufferSize = 128
diff --git a/machine/_usb/cdc/cdc.go b/machine/usb/cdc/cdc.go
similarity index 100%
rename from machine/_usb/cdc/cdc.go
rename to machine/usb/cdc/cdc.go
diff --git a/machine/_usb/cdc/doc.go b/machine/usb/cdc/doc.go
similarity index 100%
rename from machine/_usb/cdc/doc.go
rename to machine/usb/cdc/doc.go
diff --git a/machine/_usb/cdc/usbcdc.go b/machine/usb/cdc/usbcdc.go
similarity index 97%
rename from machine/_usb/cdc/usbcdc.go
rename to machine/usb/cdc/usbcdc.go
index 5b5ffbf..27b9285 100644
--- a/machine/_usb/cdc/usbcdc.go
+++ b/machine/usb/cdc/usbcdc.go
@@ -2,9 +2,9 @@ package cdc
 
 import (
 	"errors"
-	"machine"
-	"machine/usb"
-	"runtime/interrupt"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/runtime/interrupt"
 )
 
 var (
diff --git a/machine/_usb/config.go b/machine/usb/config.go
similarity index 100%
rename from machine/_usb/config.go
rename to machine/usb/config.go
diff --git a/machine/_usb/descriptor/cdc.go b/machine/usb/descriptor/cdc.go
similarity index 100%
rename from machine/_usb/descriptor/cdc.go
rename to machine/usb/descriptor/cdc.go
diff --git a/machine/_usb/descriptor/classspecific.go b/machine/usb/descriptor/classspecific.go
similarity index 100%
rename from machine/_usb/descriptor/classspecific.go
rename to machine/usb/descriptor/classspecific.go
diff --git a/machine/_usb/descriptor/configuration.go b/machine/usb/descriptor/configuration.go
similarity index 95%
rename from machine/_usb/descriptor/configuration.go
rename to machine/usb/descriptor/configuration.go
index efb9ab1..b7febb5 100644
--- a/machine/_usb/descriptor/configuration.go
+++ b/machine/usb/descriptor/configuration.go
@@ -1,7 +1,7 @@
 package descriptor
 
 import (
-	"internal/binary"
+	"github.com/goplus/emb/internal/binary"
 )
 
 const (
diff --git a/machine/_usb/descriptor/descriptor.go b/machine/usb/descriptor/descriptor.go
similarity index 96%
rename from machine/_usb/descriptor/descriptor.go
rename to machine/usb/descriptor/descriptor.go
index 852ddab..c519291 100644
--- a/machine/_usb/descriptor/descriptor.go
+++ b/machine/usb/descriptor/descriptor.go
@@ -1,7 +1,7 @@
 package descriptor
 
 import (
-	"runtime/volatile"
+	"github.com/goplus/emb/runtime/volatile"
 )
 
 const (
diff --git a/machine/_usb/descriptor/device.go b/machine/usb/descriptor/device.go
similarity index 96%
rename from machine/_usb/descriptor/device.go
rename to machine/usb/descriptor/device.go
index 0c3ee92..c2ee32f 100644
--- a/machine/_usb/descriptor/device.go
+++ b/machine/usb/descriptor/device.go
@@ -1,7 +1,7 @@
 package descriptor
 
 import (
-	"internal/binary"
+	"github.com/goplus/emb/internal/binary"
 )
 
 const (
diff --git a/machine/_usb/descriptor/doc.go b/machine/usb/descriptor/doc.go
similarity index 100%
rename from machine/_usb/descriptor/doc.go
rename to machine/usb/descriptor/doc.go
diff --git a/machine/_usb/descriptor/endpoint.go b/machine/usb/descriptor/endpoint.go
similarity index 98%
rename from machine/_usb/descriptor/endpoint.go
rename to machine/usb/descriptor/endpoint.go
index 57a1706..b7d2c0e 100644
--- a/machine/_usb/descriptor/endpoint.go
+++ b/machine/usb/descriptor/endpoint.go
@@ -1,7 +1,7 @@
 package descriptor
 
 import (
-	"internal/binary"
+	"github.com/goplus/emb/internal/binary"
 )
 
 /* Endpoint Descriptor
diff --git a/machine/_usb/descriptor/hid.go b/machine/usb/descriptor/hid.go
similarity index 98%
rename from machine/_usb/descriptor/hid.go
rename to machine/usb/descriptor/hid.go
index 06b9801..2e8a6b6 100644
--- a/machine/_usb/descriptor/hid.go
+++ b/machine/usb/descriptor/hid.go
@@ -2,8 +2,8 @@ package descriptor
 
 import (
 	"errors"
-	"internal/binary"
-	"internal/bytealg"
+	"github.com/goplus/emb/internal/binary"
+	"github.com/goplus/emb/internal/bytealg"
 )
 
 var configurationCDCHID = [configurationTypeLen]byte{
diff --git a/machine/_usb/descriptor/hidreport.go b/machine/usb/descriptor/hidreport.go
similarity index 100%
rename from machine/_usb/descriptor/hidreport.go
rename to machine/usb/descriptor/hidreport.go
diff --git a/machine/_usb/descriptor/interface.go b/machine/usb/descriptor/interface.go
similarity index 100%
rename from machine/_usb/descriptor/interface.go
rename to machine/usb/descriptor/interface.go
diff --git a/machine/_usb/descriptor/interfaceassociation.go b/machine/usb/descriptor/interfaceassociation.go
similarity index 100%
rename from machine/_usb/descriptor/interfaceassociation.go
rename to machine/usb/descriptor/interfaceassociation.go
diff --git a/machine/_usb/descriptor/joystick.go b/machine/usb/descriptor/joystick.go
similarity index 100%
rename from machine/_usb/descriptor/joystick.go
rename to machine/usb/descriptor/joystick.go
diff --git a/machine/_usb/descriptor/midi.go b/machine/usb/descriptor/midi.go
similarity index 100%
rename from machine/_usb/descriptor/midi.go
rename to machine/usb/descriptor/midi.go
diff --git a/machine/_usb/descriptor/msc.go b/machine/usb/descriptor/msc.go
similarity index 100%
rename from machine/_usb/descriptor/msc.go
rename to machine/usb/descriptor/msc.go
diff --git a/machine/_usb/doc.go b/machine/usb/doc.go
similarity index 100%
rename from machine/_usb/doc.go
rename to machine/usb/doc.go
diff --git a/machine/_usb/hid/buffer.go b/machine/usb/hid/buffer.go
similarity index 96%
rename from machine/_usb/hid/buffer.go
rename to machine/usb/hid/buffer.go
index 2674bbd..a4ffa6f 100644
--- a/machine/_usb/hid/buffer.go
+++ b/machine/usb/hid/buffer.go
@@ -1,7 +1,7 @@
 package hid
 
 import (
-	"runtime/volatile"
+	"github.com/goplus/emb/runtime/volatile"
 )
 
 const bufferSize = 128
diff --git a/machine/_usb/hid/doc.go b/machine/usb/hid/doc.go
similarity index 100%
rename from machine/_usb/hid/doc.go
rename to machine/usb/hid/doc.go
diff --git a/machine/_usb/hid/hid.go b/machine/usb/hid/hid.go
similarity index 93%
rename from machine/_usb/hid/hid.go
rename to machine/usb/hid/hid.go
index 791fd06..9c1bc4c 100644
--- a/machine/_usb/hid/hid.go
+++ b/machine/usb/hid/hid.go
@@ -2,9 +2,9 @@ package hid
 
 import (
 	"errors"
-	"machine"
-	"machine/usb"
-	"machine/usb/descriptor"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/machine/usb/descriptor"
 )
 
 // from usb-hid.go
diff --git a/machine/_usb/hid/joystick/joystick.go b/machine/usb/hid/joystick/joystick.go
similarity index 93%
rename from machine/_usb/hid/joystick/joystick.go
rename to machine/usb/hid/joystick/joystick.go
index 2c2f719..9b36b66 100644
--- a/machine/_usb/hid/joystick/joystick.go
+++ b/machine/usb/hid/joystick/joystick.go
@@ -1,10 +1,10 @@
 package joystick
 
 import (
-	"machine"
-	"machine/usb"
-	"machine/usb/descriptor"
-	"machine/usb/hid"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/machine/usb/descriptor"
+	"github.com/goplus/emb/machine/usb/hid"
 )
 
 var Joystick *joystick
diff --git a/machine/_usb/hid/joystick/state.go b/machine/usb/hid/joystick/state.go
similarity index 98%
rename from machine/_usb/hid/joystick/state.go
rename to machine/usb/hid/joystick/state.go
index 08265ab..fd4fb3f 100644
--- a/machine/_usb/hid/joystick/state.go
+++ b/machine/usb/hid/joystick/state.go
@@ -1,7 +1,7 @@
 package joystick
 
 import (
-	"machine/usb/descriptor"
+	"github.com/goplus/emb/machine/usb/descriptor"
 
 	"encoding/binary"
 )
diff --git a/machine/_usb/hid/keyboard/keyboard.go b/machine/usb/hid/keyboard/keyboard.go
similarity index 99%
rename from machine/_usb/hid/keyboard/keyboard.go
rename to machine/usb/hid/keyboard/keyboard.go
index 9f5f420..26c991d 100644
--- a/machine/_usb/hid/keyboard/keyboard.go
+++ b/machine/usb/hid/keyboard/keyboard.go
@@ -2,8 +2,8 @@ package keyboard
 
 import (
 	"errors"
-	"machine"
-	"machine/usb/hid"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb/hid"
 )
 
 // from usb-hid-keyboard.go
diff --git a/machine/_usb/hid/keyboard/keycode.go b/machine/usb/hid/keyboard/keycode.go
similarity index 100%
rename from machine/_usb/hid/keyboard/keycode.go
rename to machine/usb/hid/keyboard/keycode.go
diff --git a/machine/_usb/hid/mouse/mouse.go b/machine/usb/hid/mouse/mouse.go
similarity index 96%
rename from machine/_usb/hid/mouse/mouse.go
rename to machine/usb/hid/mouse/mouse.go
index d790bdb..ede23bd 100644
--- a/machine/_usb/hid/mouse/mouse.go
+++ b/machine/usb/hid/mouse/mouse.go
@@ -1,8 +1,8 @@
 package mouse
 
 import (
-	"machine"
-	"machine/usb/hid"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb/hid"
 )
 
 var Mouse *mouse
diff --git a/machine/_usb/msc/cbw.go b/machine/usb/msc/cbw.go
similarity index 93%
rename from machine/_usb/msc/cbw.go
rename to machine/usb/msc/cbw.go
index 7ebf346..216b140 100644
--- a/machine/_usb/msc/cbw.go
+++ b/machine/usb/msc/cbw.go
@@ -2,8 +2,8 @@ package msc
 
 import (
 	"encoding/binary"
-	"machine/usb/msc/csw"
-	"machine/usb/msc/scsi"
+	"github.com/goplus/emb/machine/usb/msc/csw"
+	"github.com/goplus/emb/machine/usb/msc/scsi"
 )
 
 const (
diff --git a/machine/_usb/msc/csw/csw.go b/machine/usb/msc/csw/csw.go
similarity index 100%
rename from machine/_usb/msc/csw/csw.go
rename to machine/usb/msc/csw/csw.go
diff --git a/machine/_usb/msc/disk.go b/machine/usb/msc/disk.go
similarity index 99%
rename from machine/_usb/msc/disk.go
rename to machine/usb/msc/disk.go
index 6624d38..9c036d5 100644
--- a/machine/_usb/msc/disk.go
+++ b/machine/usb/msc/disk.go
@@ -4,7 +4,7 @@ import (
 	"encoding/binary"
 	"errors"
 	"fmt"
-	"machine"
+	"github.com/goplus/emb/machine"
 	"time"
 )
 
diff --git a/machine/_usb/msc/msc.go b/machine/usb/msc/msc.go
similarity index 97%
rename from machine/_usb/msc/msc.go
rename to machine/usb/msc/msc.go
index d3bf8d6..62f3211 100644
--- a/machine/_usb/msc/msc.go
+++ b/machine/usb/msc/msc.go
@@ -1,11 +1,11 @@
 package msc
 
 import (
-	"machine"
-	"machine/usb"
-	"machine/usb/descriptor"
-	"machine/usb/msc/csw"
-	"machine/usb/msc/scsi"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/machine/usb/descriptor"
+	"github.com/goplus/emb/machine/usb/msc/csw"
+	"github.com/goplus/emb/machine/usb/msc/scsi"
 	"time"
 )
 
diff --git a/machine/_usb/msc/scsi.go b/machine/usb/msc/scsi.go
similarity index 98%
rename from machine/_usb/msc/scsi.go
rename to machine/usb/msc/scsi.go
index d7266ed..c2f1cea 100644
--- a/machine/_usb/msc/scsi.go
+++ b/machine/usb/msc/scsi.go
@@ -2,9 +2,9 @@ package msc
 
 import (
 	"encoding/binary"
-	"machine/usb"
-	"machine/usb/msc/csw"
-	"machine/usb/msc/scsi"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/machine/usb/msc/csw"
+	"github.com/goplus/emb/machine/usb/msc/scsi"
 )
 
 func (m *msc) scsiCmdBegin() {
diff --git a/machine/_usb/msc/scsi/scsi.go b/machine/usb/msc/scsi/scsi.go
similarity index 100%
rename from machine/_usb/msc/scsi/scsi.go
rename to machine/usb/msc/scsi/scsi.go
diff --git a/machine/_usb/msc/scsi_inquiry.go b/machine/usb/msc/scsi_inquiry.go
similarity index 98%
rename from machine/_usb/msc/scsi_inquiry.go
rename to machine/usb/msc/scsi_inquiry.go
index ae7028f..730934b 100644
--- a/machine/_usb/msc/scsi_inquiry.go
+++ b/machine/usb/msc/scsi_inquiry.go
@@ -2,8 +2,8 @@ package msc
 
 import (
 	"encoding/binary"
-	"machine/usb/msc/csw"
-	"machine/usb/msc/scsi"
+	"github.com/goplus/emb/machine/usb/msc/csw"
+	"github.com/goplus/emb/machine/usb/msc/scsi"
 )
 
 type vpdPage struct {
diff --git a/machine/_usb/msc/scsi_readwrite.go b/machine/usb/msc/scsi_readwrite.go
similarity index 98%
rename from machine/_usb/msc/scsi_readwrite.go
rename to machine/usb/msc/scsi_readwrite.go
index 1b09e13..d9854f1 100644
--- a/machine/_usb/msc/scsi_readwrite.go
+++ b/machine/usb/msc/scsi_readwrite.go
@@ -2,8 +2,8 @@ package msc
 
 import (
 	"errors"
-	"machine/usb/msc/csw"
-	"machine/usb/msc/scsi"
+	"github.com/goplus/emb/machine/usb/msc/csw"
+	"github.com/goplus/emb/machine/usb/msc/scsi"
 )
 
 var invalidWriteError = errors.New("invalid write offset or length")
diff --git a/machine/_usb/msc/scsi_unmap.go b/machine/usb/msc/scsi_unmap.go
similarity index 96%
rename from machine/_usb/msc/scsi_unmap.go
rename to machine/usb/msc/scsi_unmap.go
index 79c2426..e897802 100644
--- a/machine/_usb/msc/scsi_unmap.go
+++ b/machine/usb/msc/scsi_unmap.go
@@ -2,8 +2,8 @@ package msc
 
 import (
 	"encoding/binary"
-	"machine/usb/msc/csw"
-	"machine/usb/msc/scsi"
+	"github.com/goplus/emb/machine/usb/msc/csw"
+	"github.com/goplus/emb/machine/usb/msc/scsi"
 )
 
 type Error int
diff --git a/machine/_usb/msc/setup.go b/machine/usb/msc/setup.go
similarity index 97%
rename from machine/_usb/msc/setup.go
rename to machine/usb/msc/setup.go
index 3d5bef2..084bba3 100644
--- a/machine/_usb/msc/setup.go
+++ b/machine/usb/msc/setup.go
@@ -1,9 +1,9 @@
 package msc
 
 import (
-	"machine"
-	"machine/usb"
-	"machine/usb/msc/csw"
+	"github.com/goplus/emb/machine"
+	"github.com/goplus/emb/machine/usb"
+	"github.com/goplus/emb/machine/usb/msc/csw"
 )
 
 func setupPacketHandler(setup usb.Setup) bool {
diff --git a/machine/_usb/usb.go b/machine/usb/usb.go
similarity index 100%
rename from machine/_usb/usb.go
rename to machine/usb/usb.go