diff --git a/src/osal/osal_none.h b/src/osal/osal_none.h
new file mode 100644
index 0000000..a1f997c
--- /dev/null
+++ b/src/osal/osal_none.h
@@ -0,0 +1,204 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This file is part of the TinyUSB stack.
+ */
+
+#ifndef _TUSB_OSAL_NONE_H_
+#define _TUSB_OSAL_NONE_H_
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+//--------------------------------------------------------------------+
+// TASK API
+//--------------------------------------------------------------------+
+
+
+//--------------------------------------------------------------------+
+// Binary Semaphore API
+//--------------------------------------------------------------------+
+typedef struct
+{
+  volatile uint16_t count;
+}osal_semaphore_def_t;
+
+typedef osal_semaphore_def_t* osal_semaphore_t;
+
+static inline osal_semaphore_t osal_semaphore_create(osal_semaphore_def_t* semdef)
+{
+  semdef->count = 0;
+  return semdef;
+}
+
+static inline bool osal_semaphore_post(osal_semaphore_t sem_hdl, bool in_isr)
+{
+  (void) in_isr;
+  sem_hdl->count++;
+  return true;
+}
+
+// TODO blocking for now
+static inline bool osal_semaphore_wait (osal_semaphore_t sem_hdl, uint32_t msec)
+{
+  (void) msec;
+
+  while (sem_hdl->count == 0) { }
+  sem_hdl->count--;
+
+  return true;
+}
+
+static inline void osal_semaphore_reset(osal_semaphore_t sem_hdl)
+{
+  sem_hdl->count = 0;
+}
+
+//--------------------------------------------------------------------+
+// MUTEX API
+// Within tinyusb, mutex is never used in ISR context
+//--------------------------------------------------------------------+
+typedef osal_semaphore_def_t osal_mutex_def_t;
+typedef osal_semaphore_t osal_mutex_t;
+
+static inline osal_mutex_t osal_mutex_create(osal_mutex_def_t* mdef)
+{
+  mdef->count = 1;
+  return mdef;
+}
+
+static inline bool osal_mutex_lock (osal_mutex_t mutex_hdl, uint32_t msec)
+{
+  return osal_semaphore_wait(mutex_hdl, msec);
+}
+
+static inline bool osal_mutex_unlock(osal_mutex_t mutex_hdl)
+{
+  return osal_semaphore_post(mutex_hdl, false);
+}
+
+//--------------------------------------------------------------------+
+// QUEUE API
+//--------------------------------------------------------------------+
+#include "common/tusb_fifo.h"
+
+// extern to avoid including dcd.h and hcd.h
+#if TUSB_OPT_DEVICE_ENABLED
+extern void dcd_int_disable(uint8_t rhport);
+extern void dcd_int_enable(uint8_t rhport);
+#endif
+
+#if TUSB_OPT_HOST_ENABLED
+extern void hcd_int_disable(uint8_t rhport);
+extern void hcd_int_enable(uint8_t rhport);
+#endif
+
+typedef struct
+{
+    uint8_t role; // device or host
+    tu_fifo_t ff;
+}osal_queue_def_t;
+
+typedef osal_queue_def_t* osal_queue_t;
+
+// role device/host is used by OS NONE for mutex (disable usb isr) only
+#define OSAL_QUEUE_DEF(_role, _name, _depth, _type)       \
+  uint8_t _name##_buf[_depth*sizeof(_type)];              \
+  osal_queue_def_t _name = {                              \
+    .role = _role,                                        \
+    .ff = TU_FIFO_INIT(_name##_buf, _depth, _type, false) \
+  }
+
+// lock queue by disable USB interrupt
+static inline void _osal_q_lock(osal_queue_t qhdl)
+{
+  (void) qhdl;
+
+#if TUSB_OPT_DEVICE_ENABLED
+  if (qhdl->role == OPT_MODE_DEVICE) dcd_int_disable(TUD_OPT_RHPORT);
+#endif
+
+#if TUSB_OPT_HOST_ENABLED
+  if (qhdl->role == OPT_MODE_HOST) hcd_int_disable(TUH_OPT_RHPORT);
+#endif
+}
+
+// unlock queue
+static inline void _osal_q_unlock(osal_queue_t qhdl)
+{
+  (void) qhdl;
+
+#if TUSB_OPT_DEVICE_ENABLED
+  if (qhdl->role == OPT_MODE_DEVICE) dcd_int_enable(TUD_OPT_RHPORT);
+#endif
+
+#if TUSB_OPT_HOST_ENABLED
+  if (qhdl->role == OPT_MODE_HOST) hcd_int_enable(TUH_OPT_RHPORT);
+#endif
+}
+
+static inline osal_queue_t osal_queue_create(osal_queue_def_t* qdef)
+{
+  tu_fifo_clear(&qdef->ff);
+  return (osal_queue_t) qdef;
+}
+
+static inline bool osal_queue_receive(osal_queue_t qhdl, void* data)
+{
+  _osal_q_lock(qhdl);
+  bool success = tu_fifo_read(&qhdl->ff, data);
+  _osal_q_unlock(qhdl);
+
+  return success;
+}
+
+static inline bool osal_queue_send(osal_queue_t qhdl, void const * data, bool in_isr)
+{
+  if (!in_isr) {
+    _osal_q_lock(qhdl);
+  }
+
+  bool success = tu_fifo_write(&qhdl->ff, data);
+
+  if (!in_isr) {
+    _osal_q_unlock(qhdl);
+  }
+
+  TU_ASSERT(success);
+
+  return success;
+}
+
+static inline bool osal_queue_empty(osal_queue_t qhdl)
+{
+  // Skip queue lock/unlock since this function is primarily called
+  // with interrupt disabled before going into low power mode
+  return tu_fifo_empty(&qhdl->ff);
+}
+
+#ifdef __cplusplus
+ }
+#endif
+
+#endif /* _TUSB_OSAL_NONE_H_ */