diff --git a/.vscode/launch.json b/.vscode/launch.json
index 8ae29d750..6ab8b0076 100755
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -71,8 +71,8 @@
             // "miDebuggerPath": "/home/zhangzheng/gcc-arm-10.3-2021.07-aarch64-aarch64-none-elf/bin/aarch64-none-elf-gdb",
             // "miDebuggerPath": "/home/mkrtos-smart/toolchains/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb",
             // "miDebuggerPath": "/home/toolchains/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf/bin/aarch64-none-elf-gdb",
-            // "miDebuggerPath": "/Users/zhangzheng/gcc-arm-none-eabi-10.3-2021.10/bin/arm-none-eabi-gdb",
-            "miDebuggerPath": "/home/zhangzheng/toolchain/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi/bin/arm-none-eabi-gdb",
+            "miDebuggerPath": "/Users/zhangzheng/gcc-arm-none-eabi-10.3-2021.10/bin/arm-none-eabi-gdb",
+            // "miDebuggerPath": "/home/zhangzheng/toolchain/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi/bin/arm-none-eabi-gdb",
             "miDebuggerServerAddress": "127.0.0.1:33333",
             "MIMode": "gdb",
             "setupCommands": [
diff --git a/TODO.md b/TODO.md
index 6f672286e..dc3757eb5 100644
--- a/TODO.md
+++ b/TODO.md
@@ -29,7 +29,7 @@
 - [ ] toybox support
 - [ ] ota support
 - [ ] lvgl support
-- [ ] modubs support
+- [ ] modbus support
 
 #### must low prio
 - [ ] AT proctol support
diff --git a/mkrtos_configs/ATSURFF437_defconfig b/mkrtos_configs/ATSURFF437_defconfig
index 7c7314802..0cb45691f 100644
--- a/mkrtos_configs/ATSURFF437_defconfig
+++ b/mkrtos_configs/ATSURFF437_defconfig
@@ -50,8 +50,8 @@ CONFIG_PAGE_SHIFT=9
 CONFIG_MMU=n
 CONFIG_KNL_TEST=n
 CONFIG_ELF_LAUNCH=n
-CONFIG_THREAD_MSG_BUG_LEN=128
-CONFIG_THREAD_IPC_MSG_LEN=24
+CONFIG_THREAD_MSG_BUG_LEN=256
+CONFIG_THREAD_IPC_MSG_LEN=56
 CONFIG_THREAD_MAP_BUF_LEN=4
 CONFIG_THREAD_USER_BUF_LEN=4
 CONFIG_MSG_BUF_VADDR=0xE0000000
diff --git a/mkrtos_doc/booting.md b/mkrtos_doc/booting.md
new file mode 100644
index 000000000..edfc2695c
--- /dev/null
+++ b/mkrtos_doc/booting.md
@@ -0,0 +1,11 @@
+
+image文件打包分布：
+bootstarp(bootloader) --> dtbo(设备树) --> knl image -> appfs image
+
+appfs image
+    --> init server
+    --> block server
+    --> appfs server
+
+系统加载流程:
+    bootstarp --> knl image --> init server --> block server --> appfs server --> other appliction.
diff --git a/mkrtos_knl/drivers/at32f437/systick/systick.c b/mkrtos_knl/drivers/at32f437/systick/systick.c
index 3cbaca968..4ac68b0d4 100755
--- a/mkrtos_knl/drivers/at32f437/systick/systick.c
+++ b/mkrtos_knl/drivers/at32f437/systick/systick.c
@@ -3,6 +3,8 @@
 #include "thread.h"
 #include "futex.h"
 #include "thread_knl.h"
+#include "sleep.h"
+
 static umword_t sys_tick_cnt;
 
 umword_t sys_tick_cnt_get(void)
@@ -19,7 +21,10 @@ void SysTick_Handler(void)
         atomic_inc(&thread_get_current()->time_count);
     }
     sys_tick_cnt++;
+#if 0
     thread_timeout_check(1);
+#endif
+    thread_check_timeout();
     futex_timeout_times_tick();
     cpulock_set(status);
     thread_calc_cpu_usage();
diff --git a/mkrtos_knl/inc/knl/task.h b/mkrtos_knl/inc/knl/task.h
index cf0b49ff0..166e79fb7 100755
--- a/mkrtos_knl/inc/knl/task.h
+++ b/mkrtos_knl/inc/knl/task.h
@@ -32,6 +32,7 @@ typedef struct task
     void *nofity_point;  //!< commint point func.
     addr_t nofity_stack; //!< nofity_point_stack.
     mutex_t nofity_lock;
+    sema_t notify_sema;    //!< sema
     addr_t nofity_msg_buf; //!<
     umword_t *nofity_map_buf;
     umword_t *nofity_bitmap; //!<
diff --git a/mkrtos_knl/knl/sema.c b/mkrtos_knl/knl/sema.c
index aaf05a56f..46863bfe1 100644
--- a/mkrtos_knl/knl/sema.c
+++ b/mkrtos_knl/knl/sema.c
@@ -15,7 +15,8 @@
 static slab_t *sema_slab;
 #endif
 
-enum SEMA_OP {
+enum SEMA_OP
+{
     SEMA_UP,
     SEMA_DOWN,
 };
@@ -28,7 +29,8 @@ static void sema_mem_init(void)
 #endif
 }
 INIT_KOBJ_MEM(sema_mem_init);
-typedef struct sema_wait_item {
+typedef struct sema_wait_item
+{
     slist_head_t node;
     thread_t *thread;
 } sema_wait_item_t;
@@ -45,29 +47,47 @@ void sema_up(sema_t *obj)
     umword_t status;
 
     status = spinlock_lock(&obj->lock);
-    if (slist_is_empty(&obj->suspend_head)) {
-        if (obj->cnt < obj->max_cnt) {
+    if (slist_is_empty(&obj->suspend_head))
+    {
+        if (obj->cnt < obj->max_cnt)
+        {
             obj->cnt++;
         }
         // printk("up0 sema cnt:%d max:%d.\n", obj->cnt, obj->max_cnt);
-    } else {
+    }
+    else
+    {
         slist_head_t *first_wait_node;
         sema_wait_item_t *first_wait;
 
         first_wait_node = slist_first(&obj->suspend_head);
         first_wait = container_of(first_wait_node, sema_wait_item_t, node);
-        slist_del(first_wait_node);
-        if (ref_counter_dec_and_release(&first_wait->thread->ref, &first_wait->thread->kobj) != 1) {
-            // thread_ready_remote(first_wait->thread, FALSE);
-            thread_sleep_del_and_wakeup(first_wait->thread);
+        // assert(first_wait->thread->status == THREAD_SUSPEND);
+        if (thread_get_status(first_wait->thread) == THREAD_SUSPEND)
+        {
+            slist_del(first_wait_node);
+            if (ref_counter_dec_and_release(&first_wait->thread->ref, &first_wait->thread->kobj) != 1)
+            {
+                // thread_ready_remote(first_wait->thread, FALSE);
+                thread_sleep_del_and_wakeup(first_wait->thread);
+            }
         }
-        if (obj->cnt < obj->max_cnt) {
+        else
+        {
+            // 超时退出，但是切出来的时候切到了唤醒线程中，所以这里不是suspend状态。
+            thread_sleep_del(first_wait->thread);
+        }
+        if (obj->cnt < obj->max_cnt)
+        {
             obj->cnt++;
         }
         // printk("up1 sema cnt:%d max:%d.\n", obj->cnt, obj->max_cnt);
     }
     spinlock_set(&obj->lock, status);
-    preemption();
+    if (cpulock_get_status())
+    {
+        preemption();
+    }
 }
 umword_t sema_down(sema_t *obj, umword_t ticks)
 {
@@ -79,25 +99,31 @@ umword_t sema_down(sema_t *obj, umword_t ticks)
 
 again:
     status = spinlock_lock(&obj->lock);
-    if (obj->cnt == 0) {
+    if (obj->cnt == 0)
+    {
         sema_wait_item_init(&wait_item, th);
         ref_counter_inc(&th->ref);
         slist_add_append(&obj->suspend_head, &wait_item.node);
         remain_sleep = thread_sleep(ticks);
-        if (remain_sleep == 0 && ticks != 0) {
+        if (remain_sleep == 0 && ticks != 0)
+        {
             // 超时退出的，直接从列表中删除
             assert(slist_in_list(&wait_item.node));
             slist_del(&wait_item.node);
             ref_counter_dec(&th->ref);
         }
-        if (!(remain_sleep == 0 && ticks != 0)) {
+        else
+        {
             spinlock_set(&obj->lock, status);
-            if (cpulock_get_status()) {
+            if (cpulock_get_status())
+            {
                 preemption();
             }
             goto again;
         }
-    } else {
+    }
+    else
+    {
         assert(obj->cnt > 0);
         obj->cnt--;
         // printk("down sema cnt:%d max:%d.\n", obj->cnt, obj->max_cnt);
@@ -113,16 +139,21 @@ static void sema_syscall(kobject_t *kobj, syscall_prot_t sys_p,
     msg_tag_t tag = msg_tag_init4(0, 0, 0, -EINVAL);
     task_t *task = thread_get_current_task();
 
-    if (sys_p.prot != SEMA_PROT) {
+    if (sys_p.prot != SEMA_PROT)
+    {
         f->regs[0] = msg_tag_init4(0, 0, 0, -EPROTO).raw;
         return;
     }
-    switch (sys_p.op) {
-    case SEMA_UP: {
+    switch (sys_p.op)
+    {
+    case SEMA_UP:
+    {
         sema_up(sema);
         tag = msg_tag_init4(0, 0, 0, 0);
-    } break;
-    case SEMA_DOWN: {
+    }
+    break;
+    case SEMA_DOWN:
+    {
         umword_t ret;
 
         ret = sema_down(sema, f->regs[0]);
@@ -142,7 +173,8 @@ static sema_t *sema_create(ram_limit_t *lim, umword_t cnt, umword_t max)
 #else
     kobj = mm_limit_alloc(lim, sizeof(sema_t));
 #endif
-    if (!kobj) {
+    if (!kobj)
+    {
         return NULL;
     }
     sema_init(kobj, cnt, max);
@@ -166,10 +198,12 @@ static void sema_release_stage1(kobject_t *kobj)
         first_wait_node = slist_first(&obj->suspend_head);
         first_wait = container_of(first_wait_node, sema_wait_item_t, node);
         slist_del(first_wait_node);
-        if (ref_counter_dec_and_release(&first_wait->thread->ref, &first_wait->thread->kobj) != 1) {
+        if (ref_counter_dec_and_release(&first_wait->thread->ref, &first_wait->thread->kobj) != 1)
+        {
             thread_ready_remote(first_wait->thread, FALSE);
         }
-        if (obj->cnt < obj->max_cnt) {
+        if (obj->cnt < obj->max_cnt)
+        {
             obj->cnt++;
         }
     }
@@ -188,13 +222,16 @@ static void sema_release_stage2(kobject_t *kobj)
 
 void sema_init(sema_t *obj, int cnt, int max)
 {
-    if (max <= 0) {
+    if (max <= 0)
+    {
         max = 1;
     }
-    if (cnt < 0) {
+    if (cnt < 0)
+    {
         cnt = 0;
     }
-    if (cnt > max) {
+    if (cnt > max)
+    {
         cnt = max;
     }
     obj->cnt = cnt;
@@ -213,7 +250,8 @@ static kobject_t *sema_func(ram_limit_t *lim, umword_t arg0, umword_t arg1,
                             umword_t arg2, umword_t arg3)
 {
     sema_t *sema = sema_create(lim, arg0, arg1);
-    if (!sema) {
+    if (!sema)
+    {
         return NULL;
     }
     return &sema->kobj;
diff --git a/mkrtos_knl/knl/share_mem.c b/mkrtos_knl/knl/share_mem.c
index 502d515d8..f9e15ddf9 100644
--- a/mkrtos_knl/knl/share_mem.c
+++ b/mkrtos_knl/knl/share_mem.c
@@ -20,6 +20,7 @@
 #include "mpu.h"
 #include "init.h"
 #include "dlist.h"
+#include "printk.h"
 #if IS_ENABLED(CONFIG_BUDDY_SLAB)
 #include <slab.h>
 static slab_t *share_mem_slab;
@@ -261,6 +262,7 @@ static int share_mem_alloc_pmem(share_mem_t *obj)
         {
             return -ENOMEM;
         }
+        printk("share mem:[0x%x 0x%x]\n", obj->mem, (char *)obj->mem + obj->size);
         memset(obj->mem, 0, obj->size);
         break;
     case SHARE_MEM_CNT_DPD:
@@ -464,7 +466,7 @@ static void share_mem_release_stage2(kobject_t *kobj)
 {
     share_mem_t *sm = container_of(kobj, share_mem_t, kobj);
 
-    assert(dlist_is_empty(&sm->task_head));//TODO:有bug
+    assert(dlist_is_empty(&sm->task_head)); // TODO:有bug
 
 #if IS_ENABLED(CONFIG_MMU)
     share_mem_free_pmem(sm);
diff --git a/mkrtos_knl/knl/sleep.c b/mkrtos_knl/knl/sleep.c
index 3f75c5cbc..c65904c11 100644
--- a/mkrtos_knl/knl/sleep.c
+++ b/mkrtos_knl/knl/sleep.c
@@ -53,8 +53,8 @@ void thread_check_timeout(void)
             if (pos->times == 0)
             {
                 assert(pos->th->status == THREAD_SUSPEND);
-                thread_ready(pos->th, TRUE);
                 slist_del(&pos->node);
+                thread_ready(pos->th, TRUE);
             }
         } // !< 如果是0，则一直休眠
         pos = next;
@@ -74,7 +74,7 @@ thread_wait_entry_t *thread_sleep_del(thread_t *th)
         pos, (slist_head_t *)&wait_list,
         node)
     {
-        assert(pos->th->status == THREAD_SUSPEND);
+        // assert(pos->th->status == THREAD_SUSPEND);
         thread_wait_entry_t *next = slist_next_entry(
             pos, (slist_head_t *)wait_list,
             node);
@@ -119,6 +119,5 @@ umword_t thread_sleep(umword_t tick)
     thread_suspend(cur_th);
     spinlock_set(&lock, status);
     preemption();
-
     return entry.times;
 }
\ No newline at end of file
diff --git a/mkrtos_knl/knl/task.c b/mkrtos_knl/knl/task.c
index 3a2c3ff56..808c05070 100755
--- a/mkrtos_knl/knl/task.c
+++ b/mkrtos_knl/knl/task.c
@@ -432,6 +432,7 @@ static void task_syscall_func(kobject_t *kobj, syscall_prot_t sys_p, msg_tag_t i
         tag_task->nofity_bitmap_len = (f->regs[4]);
         tag_task->nofity_msg_buf = (addr_t)f->regs[5];
         tag_task->nofity_map_buf = (umword_t *)((addr_t)f->regs[5] + THREAD_MSG_BUG_LEN);
+        sema_init(&tag_task->notify_sema, tag_task->nofity_bitmap_len, tag_task->nofity_bitmap_len);
         tag = msg_tag_init4(0, 0, 0, 0);
     }
     break;
@@ -578,7 +579,7 @@ task_t *task_create(ram_limit_t *lim, int is_knl)
         return NULL;
     }
     task_init(tk, lim, is_knl);
-    // printk("create task is 0x%x\n", tk);
+    printk("create task is 0x%x\n", tk);
     return tk;
 }
 
diff --git a/mkrtos_knl/knl/thread.c b/mkrtos_knl/knl/thread.c
index 9936b76b4..4c14dc7ed 100755
--- a/mkrtos_knl/knl/thread.c
+++ b/mkrtos_knl/knl/thread.c
@@ -432,6 +432,7 @@ void thread_ready_remote(thread_t *th, bool_t is_sche)
  */
 void thread_ready(thread_t *th, bool_t is_sche)
 {
+    assert(th);
     bool_t ret;
     umword_t status = cpulock_lock();
 
@@ -1198,22 +1199,12 @@ msg_tag_t thread_fast_ipc_call(thread_t *to_th, entry_frame_t *f, umword_t user_
         printk("task:0x%x, notify point is not set.\n", to_task);
         return msg_tag_init4(0, 0, 0, -EIO);
     }
-_to_unlock:
-    if (GET_LSB(*to_task->nofity_bitmap, to_task->nofity_bitmap_len) == GET_LSB((~0ULL), to_task->nofity_bitmap_len))
-    {
-        thread_sched(TRUE); /*TODO:应该挂起，并在释放时唤醒*/
-        preemption();
-        goto _to_unlock;
-    }
+    sema_down(&to_task->notify_sema, 0);
     mutex_lock(&to_task->nofity_lock, 0);
-    if (GET_LSB(*to_task->nofity_bitmap, to_task->nofity_bitmap_len) == GET_LSB((~0ULL), to_task->nofity_bitmap_len))
-    {
-        mutex_unlock(&to_task->nofity_lock);
-        thread_sched(TRUE); /*TODO:应该挂起，并在释放时唤醒*/
-        preemption();
-        goto _to_unlock;
-    }
     umword_t cpu_status = cpulock_lock();
+    assert(cur_th->magic == THREAD_MAGIC);
+
+    to_task = thread_get_bind_task(to_th);
     ref_counter_inc((&to_task->ref_cn));
     //!< 执行目标线程时用的是当前线程的资源，这里还需要备份当前线程的上下文。
     ret = thread_fast_ipc_save(cur_th, to_task, (void *)(to_task->nofity_stack - 4 * 8 /*FIXME:改成宏*/)); //!< 备份栈和usp
@@ -1252,6 +1243,7 @@ _to_unlock:
                 pf_t *cur_pf = ((pf_t *)((char *)cur_th + CONFIG_THREAD_BLOCK_SIZE + 8)) - 1;
                 // 重新设置r9寄存器
                 cur_pf->regs[5] = (umword_t)(to_task->mm_space.mm_block);
+                cur_th->sp.user_sp = cur_pf;
 
                 //! 寄存器传参数
                 f->regs[0] = in_tag.raw;
@@ -1274,12 +1266,14 @@ _to_unlock:
         {
             ref_counter_dec_and_release(&to_task->ref_cn, &to_task->kobj);
             mutex_unlock(&to_task->nofity_lock);
+            sema_up(&to_task->notify_sema);
         }
     }
     else
     {
         ref_counter_dec_and_release(&to_task->ref_cn, &to_task->kobj);
         mutex_unlock(&to_task->nofity_lock);
+        sema_up(&to_task->notify_sema);
     }
     cpulock_set(cpu_status);
 
@@ -1293,6 +1287,7 @@ msg_tag_t thread_fast_ipc_replay(entry_frame_t *f)
     task_t *old_task = thread_get_bind_task(cur_th);
     int ret;
 
+    assert(cur_th->magic == THREAD_MAGIC);
     *(cur_task->nofity_bitmap) &= ~(1 << MIN(f->regs[2], cur_task->nofity_bitmap_len)); //!< 解锁bitmap
     slist_del(&cur_th->com->fast_ipc_node);                                             // 从链表中删除
 
@@ -1347,6 +1342,7 @@ msg_tag_t thread_fast_ipc_replay(entry_frame_t *f)
         in_tag = msg_tag_init4(0, 0, 0, ret);
     }
     cpulock_set(cpu_status);
+    sema_up(&old_task->notify_sema);
     if (thread_is_knl(cur_th))
     {
         arch_to_sche();
diff --git a/mkrtos_knl/knl/thread_knl.c b/mkrtos_knl/knl/thread_knl.c
index 67adf74b6..a00221f21 100755
--- a/mkrtos_knl/knl/thread_knl.c
+++ b/mkrtos_knl/knl/thread_knl.c
@@ -272,7 +272,7 @@ bool_t task_knl_kill(thread_t *kill_thread, bool_t is_knl)
     task_t *task = container_of(kill_thread->task, task_t, kobj);
     if (!is_knl)
     {
-        printk("kill %s task:0x%x, pid:%d\n", kobject_get_name(&task->kobj), task, task->pid);
+        printk("kill %s th:0x%x task:0x%x, pid:%d\n", kobject_get_name(&task->kobj), kill_thread, task, task->pid);
         umword_t status2;
 
         status2 = spinlock_lock(&del_lock);
diff --git a/mkrtos_script/build_f2.sh b/mkrtos_script/build_f2.sh
index 90e3fd657..3388a26d5 100755
--- a/mkrtos_script/build_f2.sh
+++ b/mkrtos_script/build_f2.sh
@@ -1,10 +1,10 @@
 #!/bin/bash
 
-export TOOLCHAIN=/home/zhangzheng/toolchain/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi/bin/
-export TOOLCHAIN_LIB=/home/zhangzheng/toolchain/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi/lib/gcc/arm-none-eabi/10.3.1/thumb/v7-m/nofp
+# export TOOLCHAIN=/home/zhangzheng/toolchain/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi/bin/
+# export TOOLCHAIN_LIB=/home/zhangzheng/toolchain/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi/lib/gcc/arm-none-eabi/10.3.1/thumb/v7-m/nofp
 
-# export TOOLCHAIN=/Users/zhangzheng/gcc-arm-none-eabi-10.3-2021.10/bin/
-# export TOOLCHAIN_LIB=/Users/zhangzheng/gcc-arm-none-eabi-10.3-2021.10/lib/gcc/arm-none-eabi/10.3.1/thumb/v7-m/nofp
+export TOOLCHAIN=/Users/zhangzheng/gcc-arm-none-eabi-10.3-2021.10/bin/
+export TOOLCHAIN_LIB=/Users/zhangzheng/gcc-arm-none-eabi-10.3-2021.10/lib/gcc/arm-none-eabi/10.3.1/thumb/v7-m/nofp
 
 # export TOOLCHAIN=/d/GNUArmEmbeddedToolchain/102021.10/bin/
 # export TOOLCHAIN_LIB=/d/GNUArmEmbeddedToolchain/102021.10/lib/gcc/arm-none-eabi/10.3.1/thumb/v7-m/nofp
diff --git a/mkrtos_user/lib/lwip/contrib/ports/mkrtos/lwipopts.h b/mkrtos_user/lib/lwip/contrib/ports/mkrtos/lwipopts.h
index fe6b4b37c..4730bd213 100644
--- a/mkrtos_user/lib/lwip/contrib/ports/mkrtos/lwipopts.h
+++ b/mkrtos_user/lib/lwip/contrib/ports/mkrtos/lwipopts.h
@@ -43,6 +43,9 @@
 #define MEMP_NUM_TCP_SEG 64       // MEMP_NUM_TCP_SEG:最多同时在队列中的TCP段数量
 #define MEMP_NUM_SYS_TIMEOUT 4    // MEMP_NUM_SYS_TIMEOUT:能够同时激活的timeout个数
 #define LWIP_NETCONN_SEM_PER_THREAD 0
+#define LWIP_NETIF_LOOPBACK 1
+#define LWIP_HAVE_LOOPIF 1
+#define LWIP_LOOPBACK_MAX_PBUFS 10
 // pbuf选项
 #define PBUF_POOL_SIZE 32     // PBUF_POOL_SIZE:pbuf内存池个数
 #define PBUF_POOL_BUFSIZE 1600 // PBUF_POOL_BUFSIZE:每个pbuf内存池大小
diff --git a/mkrtos_user/lib/lwip/contrib/ports/mkrtos/sys_arch.c b/mkrtos_user/lib/lwip/contrib/ports/mkrtos/sys_arch.c
index a1638519c..b90ea60a6 100644
--- a/mkrtos_user/lib/lwip/contrib/ports/mkrtos/sys_arch.c
+++ b/mkrtos_user/lib/lwip/contrib/ports/mkrtos/sys_arch.c
@@ -119,26 +119,28 @@ static int lwprot_count = 0;
 static struct sys_thread *threads = NULL;
 static u_mutex_t threads_mutex;
 
-struct sys_mbox_msg {
+struct sys_mbox_msg
+{
     struct sys_mbox_msg *next;
     void *msg;
 };
 
 static AUTO_CALL(101) void init_mutex(void)
 {
-  obj_handler_t mtx;
+    obj_handler_t mtx;
 #if SYS_LIGHTWEIGHT_PROT
-  mtx = handler_alloc();
-  assert(mtx == HANDLER_INVALID);
-  u_mutex_init(&lwprot_mutex, mtx);
+    mtx = handler_alloc();
+    assert(mtx != HANDLER_INVALID);
+    u_mutex_init(&lwprot_mutex, mtx);
 #endif
-  mtx = handler_alloc();
-  assert(mtx == HANDLER_INVALID);
-  u_mutex_init(&threads_mutex, mtx);
+    mtx = handler_alloc();
+    assert(mtx != HANDLER_INVALID);
+    u_mutex_init(&threads_mutex, mtx);
 }
 #define SYS_MBOX_SIZE 128
 
-struct sys_mbox {
+struct sys_mbox
+{
     int first, last;
     void *msgs[SYS_MBOX_SIZE];
     struct sys_sem *not_empty;
@@ -147,16 +149,19 @@ struct sys_mbox {
     int wait_send;
 };
 
-struct sys_sem {
+struct sys_sem
+{
     obj_handler_t sem;
 };
 
-struct sys_mutex {
+struct sys_mutex
+{
     // pthread_mutex_t mutex;
     u_mutex_t mutex;
 };
 
-struct sys_thread {
+struct sys_thread
+{
     struct sys_thread *next;
     pthread_t pthread;
     obj_handler_t obj_th;
@@ -195,7 +200,8 @@ introduce_thread(pthread_t id)
 
     thread = (struct sys_thread *)malloc(sizeof(struct sys_thread));
 
-    if (thread != NULL) {
+    if (thread != NULL)
+    {
         sys_thread_set_private_data(pthread_hd_get(id));
         u_mutex_lock(&threads_mutex, 0, NULL);
         thread->next = threads;
@@ -207,7 +213,8 @@ introduce_thread(pthread_t id)
     return thread;
 }
 
-struct thread_wrapper_data {
+struct thread_wrapper_data
+{
     lwip_thread_fn function;
     void *arg;
 };
@@ -247,11 +254,13 @@ sys_thread_new(const char *name, lwip_thread_fn function, void *arg, int stacksi
     pthread_setname_np(tmp, name);
 #endif
 
-    if (0 == code) {
+    if (0 == code)
+    {
         st = introduce_thread(tmp);
     }
 
-    if (NULL == st) {
+    if (NULL == st)
+    {
         LWIP_DEBUGF(SYS_DEBUG, ("sys_thread_new: pthread_create %d, st = 0x%lx\n",
                                 code, (unsigned long)st));
         abort();
@@ -271,10 +280,10 @@ void sys_unlock_tcpip_core(void)
 }
 #endif /* LWIP_TCPIP_CORE_LOCKING */
 
-static pthread_t lwip_tcpip_thread_id;
+// static pthread_t lwip_tcpip_thread_id;
 void sys_mark_tcpip_thread(void)
 {
-    lwip_tcpip_thread_id = pthread_self();
+    // lwip_tcpip_thread_id = pthread_self();
 }
 
 void sys_check_core_locking(void)
@@ -301,7 +310,8 @@ err_t sys_mbox_new(struct sys_mbox **mb, int size)
     LWIP_UNUSED_ARG(size);
 
     mbox = (struct sys_mbox *)malloc(sizeof(struct sys_mbox));
-    if (mbox == NULL) {
+    if (mbox == NULL)
+    {
         return ERR_MEM;
     }
     mbox->first = mbox->last = 0;
@@ -317,7 +327,8 @@ err_t sys_mbox_new(struct sys_mbox **mb, int size)
 
 void sys_mbox_free(struct sys_mbox **mb)
 {
-    if ((mb != NULL) && (*mb != SYS_MBOX_NULL)) {
+    if ((mb != NULL) && (*mb != SYS_MBOX_NULL))
+    {
         struct sys_mbox *mbox = *mb;
         SYS_STATS_DEC(mbox.used);
         sys_arch_sem_wait(&mbox->mutex, 0);
@@ -343,22 +354,27 @@ err_t sys_mbox_trypost(struct sys_mbox **mb, void *msg)
     LWIP_DEBUGF(SYS_DEBUG, ("sys_mbox_trypost: mbox %p msg %p\n",
                             (void *)mbox, (void *)msg));
 
-    if ((mbox->last + 1) >= (mbox->first + SYS_MBOX_SIZE)) {
+    if ((mbox->last + 1) >= (mbox->first + SYS_MBOX_SIZE))
+    {
         sys_sem_signal(&mbox->mutex);
         return ERR_MEM;
     }
 
     mbox->msgs[mbox->last % SYS_MBOX_SIZE] = msg;
 
-    if (mbox->last == mbox->first) {
+    if (mbox->last == mbox->first)
+    {
         first = 1;
-    } else {
+    }
+    else
+    {
         first = 0;
     }
 
     mbox->last++;
 
-    if (first) {
+    if (first)
+    {
         sys_sem_signal(&mbox->not_empty);
     }
 
@@ -383,7 +399,8 @@ void sys_mbox_post(struct sys_mbox **mb, void *msg)
 
     LWIP_DEBUGF(SYS_DEBUG, ("sys_mbox_post: mbox %p msg %p\n", (void *)mbox, (void *)msg));
 
-    while ((mbox->last + 1) >= (mbox->first + SYS_MBOX_SIZE)) {
+    while ((mbox->last + 1) >= (mbox->first + SYS_MBOX_SIZE))
+    {
         mbox->wait_send++;
         sys_sem_signal(&mbox->mutex);
         sys_arch_sem_wait(&mbox->not_full, 0);
@@ -393,15 +410,19 @@ void sys_mbox_post(struct sys_mbox **mb, void *msg)
 
     mbox->msgs[mbox->last % SYS_MBOX_SIZE] = msg;
 
-    if (mbox->last == mbox->first) {
+    if (mbox->last == mbox->first)
+    {
         first = 1;
-    } else {
+    }
+    else
+    {
         first = 0;
     }
 
     mbox->last++;
 
-    if (first) {
+    if (first)
+    {
         sys_sem_signal(&mbox->not_empty);
     }
 
@@ -416,21 +437,26 @@ u32_t sys_arch_mbox_tryfetch(struct sys_mbox **mb, void **msg)
 
     sys_arch_sem_wait(&mbox->mutex, 0);
 
-    if (mbox->first == mbox->last) {
+    if (mbox->first == mbox->last)
+    {
         sys_sem_signal(&mbox->mutex);
         return SYS_MBOX_EMPTY;
     }
 
-    if (msg != NULL) {
+    if (msg != NULL)
+    {
         LWIP_DEBUGF(SYS_DEBUG, ("sys_mbox_tryfetch: mbox %p msg %p\n", (void *)mbox, *msg));
         *msg = mbox->msgs[mbox->first % SYS_MBOX_SIZE];
-    } else {
+    }
+    else
+    {
         LWIP_DEBUGF(SYS_DEBUG, ("sys_mbox_tryfetch: mbox %p, null msg\n", (void *)mbox));
     }
 
     mbox->first++;
 
-    if (mbox->wait_send) {
+    if (mbox->wait_send)
+    {
         sys_sem_signal(&mbox->not_full);
     }
 
@@ -450,34 +476,43 @@ u32_t sys_arch_mbox_fetch(struct sys_mbox **mb, void **msg, u32_t timeout)
        stuff here. */
     sys_arch_sem_wait(&mbox->mutex, 0);
 
-    while (mbox->first == mbox->last) {
+    while (mbox->first == mbox->last)
+    {
         sys_sem_signal(&mbox->mutex);
 
         /* We block while waiting for a mail to arrive in the mailbox. We
            must be prepared to timeout. */
-        if (timeout != 0) {
+        if (timeout != 0)
+        {
             time_needed = sys_arch_sem_wait(&mbox->not_empty, timeout);
 
-            if (time_needed == SYS_ARCH_TIMEOUT) {
+            if (time_needed == SYS_ARCH_TIMEOUT)
+            {
                 return SYS_ARCH_TIMEOUT;
             }
-        } else {
+        }
+        else
+        {
             sys_arch_sem_wait(&mbox->not_empty, 0);
         }
 
         sys_arch_sem_wait(&mbox->mutex, 0);
     }
 
-    if (msg != NULL) {
+    if (msg != NULL)
+    {
         LWIP_DEBUGF(SYS_DEBUG, ("sys_mbox_fetch: mbox %p msg %p\n", (void *)mbox, *msg));
         *msg = mbox->msgs[mbox->first % SYS_MBOX_SIZE];
-    } else {
+    }
+    else
+    {
         LWIP_DEBUGF(SYS_DEBUG, ("sys_mbox_fetch: mbox %p, null msg\n", (void *)mbox));
     }
 
     mbox->first++;
 
-    if (mbox->wait_send) {
+    if (mbox->wait_send)
+    {
         sys_sem_signal(&mbox->not_full);
     }
 
@@ -494,16 +529,19 @@ sys_sem_new_internal(u8_t count)
     struct sys_sem *sem;
 
     sem = (struct sys_sem *)malloc(sizeof(struct sys_sem));
-    if (sem != NULL) {
+    if (sem != NULL)
+    {
         sem->sem = handler_alloc();
-        if (sem->sem == HANDLER_INVALID) {
+        if (sem->sem == HANDLER_INVALID)
+        {
             free(sem);
             return NULL;
         }
         msg_tag_t tag;
 
-        tag = facotry_create_sema(FACTORY_PROT, vpage_create_raw3(KOBJ_ALL_RIGHTS, 0, sem->sem), 0, count);
-        if (msg_tag_get_val(tag) < 0) {
+        tag = facotry_create_sema(FACTORY_PROT, vpage_create_raw3(KOBJ_ALL_RIGHTS, 0, sem->sem), count, INT_MAX);
+        if (msg_tag_get_val(tag) < 0)
+        {
             handler_free(sem->sem);
             free(sem);
             return NULL;
@@ -516,7 +554,8 @@ err_t sys_sem_new(struct sys_sem **sem, u8_t count)
 {
     SYS_STATS_INC_USED(sem);
     *sem = sys_sem_new_internal(count);
-    if (*sem == NULL) {
+    if (*sem == NULL)
+    {
         return ERR_MEM;
     }
     return ERR_OK;
@@ -526,21 +565,31 @@ u32_t sys_arch_sem_wait(struct sys_sem **s, u32_t timeout)
 {
     umword_t time_needed = 0;
     struct sys_sem *sem;
+    msg_tag_t tag;
+
     LWIP_ASSERT("invalid sem", (s != NULL) && (*s != NULL));
     sem = *s;
 
-    u_sema_down(sem->sem, timeout, &time_needed);
+    tag = u_sema_down(sem->sem, timeout, &time_needed);
+    assert(msg_tag_get_val(tag) >= 0);
 
+    if (time_needed == 0 && timeout != 0)
+    {
+        return SYS_ARCH_TIMEOUT;
+    }
     return (u32_t)(timeout - time_needed);
 }
 
 void sys_sem_signal(struct sys_sem **s)
 {
     struct sys_sem *sem;
+    msg_tag_t tag;
+
     LWIP_ASSERT("invalid sem", (s != NULL) && (*s != NULL));
     sem = *s;
 
-    u_sema_up(sem->sem);
+    tag = u_sema_up(sem->sem);
+    assert(msg_tag_get_val(tag) >= 0);
 }
 
 static void
@@ -552,7 +601,8 @@ sys_sem_free_internal(struct sys_sem *sem)
 
 void sys_sem_free(struct sys_sem **sem)
 {
-    if ((sem != NULL) && (*sem != SYS_SEM_NULL)) {
+    if ((sem != NULL) && (*sem != SYS_SEM_NULL))
+    {
         SYS_STATS_DEC(sem.used);
         sys_sem_free_internal(*sem);
     }
@@ -568,22 +618,27 @@ err_t sys_mutex_new(struct sys_mutex **mutex)
     struct sys_mutex *mtx;
 
     mtx = (struct sys_mutex *)malloc(sizeof(struct sys_mutex));
-    if (mtx != NULL) {
+    if (mtx != NULL)
+    {
         obj_handler_t mutex_obj;
 
         mutex_obj = handler_alloc();
-        if (mutex_obj == HANDLER_INVALID) {
+        if (mutex_obj == HANDLER_INVALID)
+        {
             free(mtx);
             return ERR_MEM;
         }
-        if (u_mutex_init(&mtx->mutex, mutex_obj) < 0) {
+        if (u_mutex_init(&mtx->mutex, mutex_obj) < 0)
+        {
             handler_free(mutex_obj);
             free(mtx);
             return ERR_MEM;
         }
         *mutex = mtx;
         return ERR_OK;
-    } else {
+    }
+    else
+    {
         return ERR_MEM;
     }
 }
@@ -592,7 +647,6 @@ err_t sys_mutex_new(struct sys_mutex **mutex)
  * @param mutex the mutex to lock */
 void sys_mutex_lock(struct sys_mutex **mutex)
 {
-    // pthread_mutex_lock(&((*mutex)->mutex));
     u_mutex_lock(&((*mutex)->mutex), 0, NULL);
 }
 
@@ -600,7 +654,6 @@ void sys_mutex_lock(struct sys_mutex **mutex)
  * @param mutex the mutex to unlock */
 void sys_mutex_unlock(struct sys_mutex **mutex)
 {
-    // pthread_mutex_unlock(&((*mutex)->mutex));
     u_mutex_unlock(&((*mutex)->mutex));
 }
 
@@ -623,7 +676,8 @@ sys_thread_sem_free(void *data)
 {
     sys_sem_t *sem = (sys_sem_t *)(data);
 
-    if (sem) {
+    if (sem)
+    {
         sys_sem_free(sem);
         free(sem);
     }
@@ -649,7 +703,8 @@ sys_sem_t *
 sys_arch_netconn_sem_get(void)
 {
     sys_sem_t *sem = (sys_sem_t *)pthread_getspecific(sys_thread_sem_key);
-    if (!sem) {
+    if (!sem)
+    {
         sem = sys_thread_sem_alloc();
     }
     LWIP_DEBUGF(SYS_DEBUG, ("sys_thread_sem_get s=%p\n", (void *)sem));
@@ -729,14 +784,17 @@ sys_arch_protect(void)
     /* Note that for the UNIX port, we are using a lightweight mutex, and our
      * own counter (which is locked by the mutex). The return code is not actually
      * used. */
-    if (lwprot_thread != sys_thread_get_private_data_self()) {
+    // printf("thread:%d\n", lwprot_thread);
+    if (lwprot_thread != sys_thread_get_private_data_self())
+    {
         /* We are locking the mutex where it has not been locked before *
          * or is being locked by another thread */
         // pthread_mutex_lock(&lwprot_mutex);
         u_mutex_lock(&lwprot_mutex, 0, NULL);
         lwprot_thread = sys_thread_get_private_data_self();
         lwprot_count = 1;
-    } else
+    }
+    else
         /* It is already locked by THIS thread */
         lwprot_count++;
     return 0;
@@ -752,9 +810,11 @@ an operating system.
 void sys_arch_unprotect(sys_prot_t pval)
 {
     LWIP_UNUSED_ARG(pval);
-    if (lwprot_thread == sys_thread_get_private_data_self()) {
+    if (lwprot_thread == sys_thread_get_private_data_self())
+    {
         lwprot_count--;
-        if (lwprot_count == 0) {
+        if (lwprot_count == 0)
+        {
             lwprot_thread = (umword_t)0xDEAD;
             // pthread_mutex_unlock(&lwprot_mutex);
             u_mutex_unlock(&lwprot_mutex);
diff --git a/mkrtos_user/lib/lwip/src/include/lwip/sockets.h b/mkrtos_user/lib/lwip/src/include/lwip/sockets.h
index 3e3db2337..c4b045e2a 100644
--- a/mkrtos_user/lib/lwip/src/include/lwip/sockets.h
+++ b/mkrtos_user/lib/lwip/src/include/lwip/sockets.h
@@ -102,6 +102,9 @@ struct sockaddr_in6 {
 
 struct sockaddr {
   u8_t        sa_len;
+#ifdef MKRTOS
+	unsigned char is_null;
+#endif
   sa_family_t sa_family;
   char        sa_data[14];
 };
diff --git a/mkrtos_user/lib/mlibc/include/sys/socket.h b/mkrtos_user/lib/mlibc/include/sys/socket.h
index 2b7771094..7c417729e 100644
--- a/mkrtos_user/lib/mlibc/include/sys/socket.h
+++ b/mkrtos_user/lib/mlibc/include/sys/socket.h
@@ -369,6 +369,7 @@ struct linger {
 struct sockaddr {
 #ifdef MKRTOS
 	unsigned char sa_len;
+	unsigned char is_null;
 #endif
 	sa_family_t sa_family;
 	char sa_data[14];
diff --git a/mkrtos_user/lib/sys/inc/u_factory.h b/mkrtos_user/lib/sys/inc/u_factory.h
index 3f8794fc6..2ee0ae7e2 100644
--- a/mkrtos_user/lib/sys/inc/u_factory.h
+++ b/mkrtos_user/lib/sys/inc/u_factory.h
@@ -18,4 +18,4 @@ msg_tag_t factory_create_thread(obj_handler_t obj, vpage_t vpage);
 msg_tag_t factory_create_thread_vcpu(obj_handler_t obj, vpage_t vpage);
 msg_tag_t factory_create_task(obj_handler_t obj, vpage_t vpage);
 msg_tag_t facotry_create_share_mem(obj_handler_t obj, vpage_t vpage, share_mem_type_t mem_type, umword_t size);
-msg_tag_t facotry_create_sema(obj_handler_t obj, vpage_t vpage, int cnt, uint32_t max);
+msg_tag_t facotry_create_sema(obj_handler_t obj, vpage_t vpage, int cnt, int max);
diff --git a/mkrtos_user/lib/sys/src/u_factory.c b/mkrtos_user/lib/sys/src/u_factory.c
index f806f2b02..42ee5a4d0 100644
--- a/mkrtos_user/lib/sys/src/u_factory.c
+++ b/mkrtos_user/lib/sys/src/u_factory.c
@@ -105,7 +105,7 @@ msg_tag_t facotry_create_share_mem(obj_handler_t obj, vpage_t vpage, share_mem_t
 
     return tag;
 }
-msg_tag_t facotry_create_sema(obj_handler_t obj, vpage_t vpage, int cnt, uint32_t max)
+msg_tag_t facotry_create_sema(obj_handler_t obj, vpage_t vpage, int cnt, int max)
 {
     register volatile umword_t r0 asm(ARCH_REG_0);
 
diff --git a/mkrtos_user/lib/sys/src/u_mutex.c b/mkrtos_user/lib/sys/src/u_mutex.c
index 588a0b706..d33576a8d 100644
--- a/mkrtos_user/lib/sys/src/u_mutex.c
+++ b/mkrtos_user/lib/sys/src/u_mutex.c
@@ -24,6 +24,7 @@ int u_mutex_init(u_mutex_t *lock, obj_handler_t sema_hd)
     {
         return msg_tag_get_val(tag);
     }
+    lock->obj = sema_hd;
     return 0;
 }
 void u_mutex_lock(u_mutex_t *lock, umword_t timeout, umword_t *remain_times)
diff --git a/mkrtos_user/lib/sys_svr/src/net_cli.c b/mkrtos_user/lib/sys_svr/src/net_cli.c
index f8f89624f..281ef3371 100644
--- a/mkrtos_user/lib/sys_svr/src/net_cli.c
+++ b/mkrtos_user/lib/sys_svr/src/net_cli.c
@@ -64,7 +64,7 @@ int net_accept(sd_t s, struct sockaddr *addr, socklen_t *addrlen)
     }
     *addr = rpc_addr.data;
     *addrlen = rpc_addrlen.data;
-    return msg_tag_get_val(tag);
+    return mk_sd_init2(hd, msg_tag_get_val(tag)).raw;
 }
 RPC_GENERATION_CALL3(net_t, NET_PROT, NET_BIND, bind,
                      rpc_int_t, rpc_int_t, RPC_DIR_IN, RPC_TYPE_DATA, s,
@@ -345,7 +345,7 @@ int net_recv(int s, void *mem, size_t len, int flags)
             .data = mem + rlen,
             // .len = MIN(len, sizeof(rpc_mem.data)),
         };
-        r_once_len = MIN(sizeof(rpc_mem.data), len - rlen);
+        r_once_len = MIN(128, len - rlen);
         rpc_mem.len = r_once_len;
         rpc_size_t_t rpc_len = {
             .data = r_once_len,
@@ -363,7 +363,7 @@ int net_recv(int s, void *mem, size_t len, int flags)
         }
     }
 
-    return msg_tag_get_val(tag);
+    return rlen;
 }
 RPC_GENERATION_CALL6(net_t, NET_PROT, NET_RECVFROM, recvfrom,
                      rpc_int_t, rpc_int_t, RPC_DIR_IN, RPC_TYPE_DATA, s,
@@ -375,7 +375,7 @@ RPC_GENERATION_CALL6(net_t, NET_PROT, NET_RECVFROM, recvfrom,
 int net_recvfrom(int s, void *mem, size_t len, int flags,
                  struct sockaddr *from, socklen_t *fromlen)
 {
-    if (mem == NULL || from == NULL || fromlen == NULL)
+    if (mem == NULL)
     {
         return -EINVAL;
     }
@@ -390,12 +390,20 @@ int net_recvfrom(int s, void *mem, size_t len, int flags,
         .data = flags,
     };
 
-    rpc_socketaddr_t_t rpc_form = {
-        .data = *from,
-    };
-    rpc_socklen_t_t rpc_fromlen = {
-        .data = *fromlen,
-    };
+    rpc_socketaddr_t_t rpc_form = {};
+    if (from)
+    {
+        rpc_form.data = *from;
+    }
+    else
+    {
+        rpc_form.data.is_null = 1;
+    }
+    rpc_socklen_t_t rpc_fromlen = {};
+    if (fromlen)
+    {
+        rpc_fromlen.data = *fromlen;
+    }
     msg_tag_t tag;
 
     int rlen = 0;
@@ -407,7 +415,7 @@ int net_recvfrom(int s, void *mem, size_t len, int flags,
             .data = mem + rlen,
             // .len = MIN(len, sizeof(rpc_mem.data)),
         };
-        r_once_len = MIN(sizeof(rpc_mem.data), len - rlen);
+        r_once_len = MIN(128, len - rlen);
         rpc_mem.len = r_once_len;
         rpc_size_t_t rpc_len = {
             .data = r_once_len,
@@ -425,7 +433,7 @@ int net_recvfrom(int s, void *mem, size_t len, int flags,
         }
     }
 
-    return msg_tag_get_val(tag);
+    return rlen;
 }
 RPC_GENERATION_CALL4(net_t, NET_PROT, NET_SEND, send,
                      rpc_int_t, rpc_int_t, RPC_DIR_IN, RPC_TYPE_DATA, s,
@@ -460,7 +468,7 @@ int net_send(int s, const void *dataptr, size_t size, int flags)
             .data = (void *)dataptr + rlen,
             // .len = MIN(len, sizeof(rpc_mem.data)),
         };
-        w_once_len = MIN(sizeof(rpc_mem.data), size - rlen);
+        w_once_len = MIN(128, size - rlen);
         rpc_mem.len = w_once_len;
         rpc_size_t_t rpc_len = {
             .data = w_once_len,
@@ -478,7 +486,7 @@ int net_send(int s, const void *dataptr, size_t size, int flags)
         }
     }
 
-    return msg_tag_get_val(tag);
+    return rlen;
 }
 RPC_GENERATION_CALL6(net_t, NET_PROT, NET_SENDTO, sendto,
                      rpc_int_t, rpc_int_t, RPC_DIR_IN, RPC_TYPE_DATA, s,
@@ -490,7 +498,7 @@ RPC_GENERATION_CALL6(net_t, NET_PROT, NET_SENDTO, sendto,
 int net_sendto(int s, const void *dataptr, size_t size, int flags,
                const struct sockaddr *to, socklen_t tolen)
 {
-    if (dataptr == NULL || to == NULL)
+    if (dataptr == NULL)
     {
         return -EINVAL;
     }
@@ -504,9 +512,15 @@ int net_sendto(int s, const void *dataptr, size_t size, int flags,
     rpc_int_t rpc_flags = {
         .data = flags,
     };
-    rpc_socketaddr_t_t rpc_to = {
-        .data = *to,
-    };
+    rpc_socketaddr_t_t rpc_to = {};
+    if (to)
+    {
+        rpc_to.data = *to;
+    }
+    else
+    {
+        rpc_to.data.is_null = 1;
+    }
     rpc_socklen_t_t rpc_tolen = {
         .data = tolen,
     };
@@ -520,7 +534,7 @@ int net_sendto(int s, const void *dataptr, size_t size, int flags,
             .data = (void *)(dataptr + rlen),
             // .len = MIN(len, sizeof(rpc_mem.data)),
         };
-        w_once_len = MIN(sizeof(rpc_mem.data), size - rlen);
+        w_once_len = MIN(128, size - rlen);
         rpc_mem.len = w_once_len;
         rpc_size_t_t rpc_len = {
             .data = w_once_len,
@@ -538,7 +552,7 @@ int net_sendto(int s, const void *dataptr, size_t size, int flags,
         }
     }
 
-    return msg_tag_get_val(tag);
+    return rlen;
 }
 RPC_GENERATION_CALL3(net_t, NET_PROT, NET_SOCKET, socket,
                      rpc_int_t, rpc_int_t, RPC_DIR_IN, RPC_TYPE_DATA, s,
diff --git a/mkrtos_user/lib/sys_svr/src/net_svr.c b/mkrtos_user/lib/sys_svr/src/net_svr.c
index 637950f86..797df02c9 100644
--- a/mkrtos_user/lib/sys_svr/src/net_svr.c
+++ b/mkrtos_user/lib/sys_svr/src/net_svr.c
@@ -192,7 +192,26 @@ RPC_GENERATION_OP_DISPATCH6(net_t, NET_PROT, NET_RECVFROM, recvfrom,
     {
         return -ENOSYS;
     }
-    ret = obj->op->recvfrom(s->data, mem->data, len->data, flags->data, &from->data, &fromlen->data);
+    socketaddr_t *p_from;
+    socklen_t *p_fromlen;
+
+    if (from->data.is_null == 1)
+    {
+        p_from = NULL;
+    }
+    else
+    {
+        p_from = &from->data;
+    }
+    if (!p_from)
+    {
+        p_fromlen = NULL;
+    }
+    else
+    {
+        p_fromlen = &fromlen->data;
+    }
+    ret = obj->op->recvfrom(s->data, mem->data, len->data, flags->data, p_from, p_fromlen);
     return ret;
 }
 // ssize_t (*recvmsg)(int s, struct msghdr *message, int flags);
@@ -257,7 +276,17 @@ RPC_GENERATION_OP_DISPATCH6(net_t, NET_PROT, NET_SENDTO, sendto,
     {
         return -ENOSYS;
     }
-    ret = obj->op->sendto(s->data, mem->data, size->data, flags->data, &to->data, tolen->data);
+    socketaddr_t *p_to;
+
+    if (to->data.is_null == 1)
+    {
+        p_to = NULL;
+    }
+    else
+    {
+        p_to = &to->data;
+    }
+    ret = obj->op->sendto(s->data, mem->data, size->data, flags->data, p_to, tolen->data);
     return ret;
 }
 // int (*socket)(int domain, int type, int protocol);
diff --git a/mkrtos_user/lib/sys_util/src/u_fast_ipc.c b/mkrtos_user/lib/sys_util/src/u_fast_ipc.c
index a85786a5e..896c4dc7f 100644
--- a/mkrtos_user/lib/sys_util/src/u_fast_ipc.c
+++ b/mkrtos_user/lib/sys_util/src/u_fast_ipc.c
@@ -9,7 +9,7 @@
 #include <u_task.h>
 #include <u_thread.h>
 #include <u_types.h>
-
+#include <stdio.h>
 #define MAGIC_NS_USERPID 0xbabababa
 
 int fast_ipc_setsp(int i, void *stack);
@@ -43,8 +43,10 @@ static int fast_ipc_dat_copy(ipc_msg_t *dst_ipc, ipc_msg_t *src_ipc, msg_tag_t t
 }
 static void update_map_buf(void)
 {
-    for (int i = 0; i < CONFIG_THREAD_MAP_BUF_LEN; i++) {
-        if (cons_map_buf[i] == 0) {
+    for (int i = 0; i < CONFIG_THREAD_MAP_BUF_LEN; i++)
+    {
+        if (cons_map_buf[i] == 0)
+        {
             cons_map_buf[i] = vpage_create_raw3(0, 0, handler_alloc()).raw; /*TODO:申请失败检查*/
         }
     }
@@ -59,19 +61,23 @@ static msg_tag_t process_ipc(int j, umword_t obj, long tag)
     msg = (ipc_msg_t *)(&cons_msg_buf[j * MSG_BUG_LEN]);
     ret_tag = msg_tag_init4(0, 0, 0, -EIO);
     svr_obj = (rpc_svr_obj_t *)obj;
-    if (svr_obj == NULL) {
+    if (svr_obj == NULL)
+    {
         ret_tag = msg_tag_init4(0, 0, 0, -EACCES);
         goto end;
     }
-    if (svr_obj == (void *)MAGIC_NS_USERPID) {
+    if (svr_obj == (void *)MAGIC_NS_USERPID)
+    {
         /*获取ns的user id*/
         svr_obj = meta_find_svr_obj(NS_PROT);
     }
-    if (svr_obj == NULL) {
+    if (svr_obj == NULL)
+    {
         ret_tag = msg_tag_init4(0, 0, 0, -EACCES);
         goto end;
     }
-    if (svr_obj->dispatch) {
+    if (svr_obj->dispatch)
+    {
         ret_tag = svr_obj->dispatch(svr_obj, msg_tag_init(tag), msg);
     }
 end:
@@ -79,10 +85,13 @@ end:
 }
 static void update_map_buf_last(void)
 {
-    for (int i = 0; i < CONFIG_THREAD_MAP_BUF_LEN; i++) {
+    for (int i = 0; i < CONFIG_THREAD_MAP_BUF_LEN; i++)
+    {
         vpage_t vpage = vpage_create_raw(cons_map_buf[i]);
-        if (handler_is_used(vpage.addr)) {
-            if (task_obj_valid(TASK_THIS, vpage.addr, 0).prot == 1) {
+        if (handler_is_used(vpage.addr))
+        {
+            if (task_obj_valid(TASK_THIS, vpage.addr, 0).prot == 1)
+            {
                 cons_map_buf[i] = vpage_create_raw3(0, 0, handler_alloc()).raw;
             }
         }
@@ -93,10 +102,10 @@ static void fast_ipc_goto_process(int j, long tag, umword_t obj, umword_t arg1,
     msg_tag_t ret_tag;
     ipc_msg_t *msg;
 
-    msg =  (void *)(&cons_msg_buf[j * MSG_BUG_LEN]);
+    msg = (void *)(&cons_msg_buf[j * MSG_BUG_LEN]);
     thread_msg_buf_set(-1, msg);
     update_map_buf();
-    msg->user[3] = cons_thread_th[j];//设置私有变量，FIXME: 一种更加通用的方法
+    msg->user[3] = cons_thread_th[j]; // 设置私有变量，FIXME: 一种更加通用的方法
     task_com_unlock(TASK_THIS);
     ret_tag = process_ipc(j, obj, tag);
     task_com_lock(TASK_THIS);
@@ -107,8 +116,10 @@ static void fast_ipc_goto_process(int j, long tag, umword_t obj, umword_t arg1,
 static __attribute__((optimize(0))) void fast_ipc_com_point(msg_tag_t tag, umword_t arg0, umword_t arg1, umword_t arg2)
 {
     int i;
-    for (i = 0; i < stack_array_nr; i++) {
-        if ((cons_stack_bitmap & (1 << i)) == 0) {
+    for (i = 0; i < stack_array_nr; i++)
+    {
+        if ((cons_stack_bitmap & (1 << i)) == 0)
+        {
             cons_stack_bitmap |= (1 << i);
             break;
         }
@@ -126,16 +137,24 @@ int u_fast_ipc_init(uint8_t *stack_array, uint8_t *msg_buf_array, int stack_msgb
     cons_msg_buf = msg_buf_array;
     cons_thread_th = threads_obj;
     ipc_msg_t *msg = (void *)cons_msg_buf_main;
-    for (int i = 0; i < CONFIG_THREAD_MAP_BUF_LEN; i++) {
+    for (int i = 0; i < CONFIG_THREAD_MAP_BUF_LEN; i++)
+    {
         cons_map_buf[i] = vpage_create_raw3(0, 0, handler_alloc()).raw;
         msg->map_buf[i] = cons_map_buf[i];
     }
+#if 1
+    for (int i = 0; i < stack_msgbuf_array_num; i++)
+    {
+        printf("stack 0x%x %x\n", stack_array + stack_size * i, stack_size);
+    }
+#endif
     msg->user[0] = (umword_t)((char *)fake_pthread + sizeof(fake_pthread));
 
     tag = task_set_com_point(TASK_THIS, &fast_ipc_com_point, (addr_t)com_stack,
                              sizeof(com_stack), (void *)(&cons_stack_bitmap),
                              stack_msgbuf_array_num, cons_msg_buf_main);
-    if (msg_tag_get_val(tag) < 0) {
+    if (msg_tag_get_val(tag) < 0)
+    {
         return msg_tag_get_val(tag);
     }
     return msg_tag_get_val(tag);
diff --git a/mkrtos_user/server/init/board/ATSURFF437/init.cfg b/mkrtos_user/server/init/board/ATSURFF437/init.cfg
index c7716bf39..9c146a110 100644
--- a/mkrtos_user/server/init/board/ATSURFF437/init.cfg
+++ b/mkrtos_user/server/init/board/ATSURFF437/init.cfg
@@ -1,7 +1,6 @@
 #一次读取一行，每行代表启动的应用程序
 block /block
 appfs -m /bin -d /block
-# cpiofs -m /bin
 # fatfs
 # pin
 # i2c
diff --git a/mkrtos_user/server/init/src/ns.c b/mkrtos_user/server/init/src/ns.c
new file mode 100644
index 000000000..74f2f1909
--- /dev/null
+++ b/mkrtos_user/server/init/src/ns.c
@@ -0,0 +1,28 @@
+
+#include "ns.h"
+#include "u_types.h"
+// #include "ns_types.h"
+
+// 其他进程可以注册节点进来，并且可以注册子节点进来，子节点可以注册更多的子节点进来。
+// 可以注册两种节点DUMMY和SVR节点
+// 只有DUMMY节点里面可以注册SVR节点
+// 查找节点时采取最大服务匹配的原则，即匹配到最后一个SVR节点时，返回最后一个SVR节点的HD，以及截断的位置。
+
+#define NS_NODE_NAME_LEN 32
+
+typedef enum node_type
+{
+    NODE_TYPE_DUMMY,
+    NODE_TYPE_SVR,
+} node_type_t;
+
+typedef struct ns_node
+{
+    char name[NS_NODE_NAME_LEN];
+    node_type_t type;
+    struct ns_node *next;
+    struct ns_node *sub;
+    int ref;
+} ns_node_t;
+
+
diff --git a/mkrtos_user/server/init/src/ns.h b/mkrtos_user/server/init/src/ns.h
new file mode 100644
index 000000000..45dcbb04b
--- /dev/null
+++ b/mkrtos_user/server/init/src/ns.h
@@ -0,0 +1,3 @@
+#pragma once
+
+
diff --git a/mkrtos_user/server/init/src/test/sema_test.c b/mkrtos_user/server/init/src/test/sema_test.c
index f8dec4212..b92ca3d40 100644
--- a/mkrtos_user/server/init/src/test/sema_test.c
+++ b/mkrtos_user/server/init/src/test/sema_test.c
@@ -30,16 +30,18 @@ static pthread_t pth1;
 static pthread_t pth2;
 static pthread_t pth3;
 static obj_handler_t sema_hd2;
-#define TEST_CN 10
+#define TEST_CN 100
 static void *thread_th1(void *arg)
 {
     int j = 0;
-    while (1) {
+    while (1)
+    {
         printf("sema_up start\n");
         u_sema_up(sema_hd2);
         u_sleep_ms(100);
         printf("sema_up end\n");
-        if (j == TEST_CN * 2 + 2) {
+        if (j == TEST_CN * 2 + 2)
+        {
             break;
         }
         j++;
@@ -50,12 +52,14 @@ static void *thread_th1(void *arg)
 static void *thread_th2(void *arg)
 {
     int j = 0;
-    while (1) {
+    while (1)
+    {
         printf("sema_down start\n");
         u_sema_down(sema_hd2, 0, NULL);
         u_sleep_ms(50);
         printf("sema_down end\n");
-        if (j == TEST_CN) {
+        if (j == TEST_CN)
+        {
             break;
         }
         j++;
@@ -66,12 +70,14 @@ static void *thread_th2(void *arg)
 static void *thread_th3(void *arg)
 {
     int j = 0;
-    while (1) {
+    while (1)
+    {
         printf("sema_down2 start\n");
         u_sema_down(sema_hd2, 0, NULL);
         u_sleep_ms(50);
         printf("sema_down2 end\n");
-        if (j == TEST_CN) {
+        if (j == TEST_CN)
+        {
             break;
         }
         j++;
@@ -91,31 +97,42 @@ static void u_sema_test2(CuTest *tc)
     CuAssert(tc, "pthread_create fail.\n", pthread_create(&pth1, NULL, thread_th1, NULL) == 0);
     CuAssert(tc, "pthread_create fail.\n", pthread_create(&pth2, NULL, thread_th2, NULL) == 0);
     CuAssert(tc, "pthread_create fail.\n", pthread_create(&pth3, NULL, thread_th3, NULL) == 0);
-    if (pth1 != PTHREAD_NULL) {
+    if (pth1 != PTHREAD_NULL)
+    {
         CuAssert(tc, "pthread_join fail.\n", pthread_join(pth1, NULL) == 0);
     }
-    if (pth2 != PTHREAD_NULL) {
+    if (pth2 != PTHREAD_NULL)
+    {
         CuAssert(tc, "pthread_join fail.\n", pthread_join(pth2, NULL) == 0);
     }
-    if (pth3 != PTHREAD_NULL) {
+    if (pth3 != PTHREAD_NULL)
+    {
         CuAssert(tc, "pthread_join fail.\n", pthread_join(pth3, NULL) == 0);
     }
 }
 static void u_sema_test3(CuTest *tc)
 {
     msg_tag_t tag;
-    obj_handler_t sema_hd2;
     umword_t reamin_times;
 
-    tag = facotry_create_sema(FACTORY_PROT,
-                              vpage_create_raw3(KOBJ_ALL_RIGHTS, 0, sema_hd2), 0, 1);
-    CuAssert(tc, "hd alloc fail.\n", msg_tag_get_val(tag) >= 0);
-    for (int i = 0; i < 5; i++) {
-        tag = u_sema_down(sema_hd2, 100, &reamin_times);
-        CuAssert(tc, "sema down fail.\n", msg_tag_get_val(tag) >= 0);
-        CuAssert(tc, "sema down fail.\n", reamin_times == 0);
+    for (int j = 0; j < 100; j++)
+    {
+        obj_handler_t sema_hd2;
+
+        sema_hd2 = handler_alloc();
+        CuAssert(tc, "hd alloc fail.\n", sema_hd2 != HANDLER_INVALID);
+
+        tag = facotry_create_sema(FACTORY_PROT,
+                                  vpage_create_raw3(KOBJ_ALL_RIGHTS, 0, sema_hd2), 0, 1);
+        CuAssert(tc, "hd alloc fail.\n", msg_tag_get_val(tag) >= 0);
+        for (int i = 0; i < 5; i++)
+        {
+            tag = u_sema_down(sema_hd2, 10, &reamin_times);
+            CuAssert(tc, "sema down fail.\n", msg_tag_get_val(tag) >= 0);
+            CuAssert(tc, "sema down fail.\n", reamin_times == 0);
+        }
+        handler_free_umap(sema_hd2);
     }
-    handler_free_umap(sema_hd2);
 }
 static CuSuite suite;
 CuSuite *sema_test_suite(void)
diff --git a/mkrtos_user/server/net/src/ethernetif.c b/mkrtos_user/server/net/src/ethernetif.c
index e5608e696..5e9868fdb 100644
--- a/mkrtos_user/server/net/src/ethernetif.c
+++ b/mkrtos_user/server/net/src/ethernetif.c
@@ -64,7 +64,9 @@ static err_t low_level_output(struct netif *netif, struct pbuf *p)
 	int ret;
 
 	memcpy((void *)send_shm_addr, p->payload, p->len);
+	// printf("start write.\n");
 	ret = blk_drv_cli_write(net_drv_hd, send_shm_hd, p->len, 0);
+	// printf("start end.\n");
 	return ret >= 0 ? ERR_OK : ERR_IF;
 }
 
diff --git a/mkrtos_user/server/net/src/heap_stack.c b/mkrtos_user/server/net/src/heap_stack.c
index 502c14a3a..665fc845c 100644
--- a/mkrtos_user/server/net/src/heap_stack.c
+++ b/mkrtos_user/server/net/src/heap_stack.c
@@ -1,6 +1,6 @@
 #include <u_util.h>
 #if !IS_ENABLED(CONFIG_MMU)
-#define HEAP_SIZE (32 * 1024)
+#define HEAP_SIZE (16 * 1024)
 #define STACK_SIZE (2048)
 
 #if defined(__CC_ARM)
diff --git a/mkrtos_user/server/net/src/main.c b/mkrtos_user/server/net/src/main.c
index b5f4efb39..357365383 100644
--- a/mkrtos_user/server/net/src/main.c
+++ b/mkrtos_user/server/net/src/main.c
@@ -23,7 +23,7 @@ static umword_t addr;
 static umword_t size;
 obj_handler_t net_drv_hd;
 
-#define STACK_COM_ITME_SIZE (2 * 1024 + 512 /*sizeof(struct pthread) + TP_OFFSET*/)
+#define STACK_COM_ITME_SIZE (2 * 1024/*sizeof(struct pthread) + TP_OFFSET*/)
 #define STACK_NUM           4
 ATTR_ALIGN(8)
 static uint8_t stack_coms[STACK_COM_ITME_SIZE * STACK_NUM];
@@ -43,7 +43,8 @@ int main(int args, char *argv[])
     int ret;
     msg_tag_t tag;
     obj_handler_t hd;
-
+    task_set_obj_name(TASK_THIS, TASK_THIS, "tk_net");
+    task_set_obj_name(TASK_THIS, THREAD_MAIN, "th_net");
     printf("net startup..\n");
     fast_ipc_init();
     ret = rpc_meta_init(THREAD_MAIN, &hd);
@@ -97,12 +98,14 @@ again:
         return -1;
     }
     cons_write_str("net mount success\n");
-    net_test();
+    // net_test();
     while (1) {
         if (msg_tag_get_prot(u_sema_down(sem_hd, 0, NULL)) < 0) {
             printf("error.\n");
         }
+      //  printf("start read.\n");
         int ret = blk_drv_cli_read(net_drv_hd, shm_hd, 0, 0);
+      //  printf("end read.\n");
 
         if (ret > 0) {
             lwip_pkt_handle_raw((uint8_t *)addr, ret);
diff --git a/mkrtos_user/server/net/src/test/net_test.c b/mkrtos_user/server/net/src/test/net_test.c
index d41d7949c..693c473c8 100644
--- a/mkrtos_user/server/net/src/test/net_test.c
+++ b/mkrtos_user/server/net/src/test/net_test.c
@@ -101,7 +101,7 @@ static int tcp_client(void)
     // 设置服务器地址
     memset(&server_addr, 0, sizeof(server_addr));
     server_addr.sin_family = AF_INET;
-    server_addr.sin_addr.s_addr = inet_addr("192.168.3.10"); // 使用本机IP地址
+    server_addr.sin_addr.s_addr = inet_addr("127.0.0.1"); // 使用本机IP地址
     server_addr.sin_port = htons(PORT);
 
     // 连接到服务器
diff --git a/mkrtos_user/user/app/test/main.c b/mkrtos_user/user/app/test/main.c
index aecb1cfe2..74b874b90 100644
--- a/mkrtos_user/user/app/test/main.c
+++ b/mkrtos_user/user/app/test/main.c
@@ -10,8 +10,11 @@
 #include "mm_test.h"
 #include <u_sleep.h>
 #include "net_test.h"
+#include "u_task.h"
 int main(int argc, char *argv[])
 {
+    task_set_obj_name(TASK_THIS, TASK_THIS, "tk_tst");
+    task_set_obj_name(TASK_THIS, THREAD_MAIN, "th_tst");
     for (int i = 0; i < argc; i++)
     {
         printf("argv[%d]: %s\n", i, argv[i]);
diff --git a/mkrtos_user/user/app/test/net_test.c b/mkrtos_user/user/app/test/net_test.c
index ec63a0336..c488f2a8b 100644
--- a/mkrtos_user/user/app/test/net_test.c
+++ b/mkrtos_user/user/app/test/net_test.c
@@ -58,22 +58,21 @@ static int tcp_server(void)
 
     printf("Client connected!\n");
 
-    // 发送数据
-    const char *message = "Hello from server!";
-    send(client_socket, message, strlen(message), 0);
-
-    // 接收数据
-    memset(buffer, 0, BUFFER_SIZE);
-    ssize_t bytes_received = recv(client_socket, buffer, BUFFER_SIZE - 1, 0);
-    if (bytes_received < 0)
+    while (1)
     {
-        perror("recv failed");
-        close(server_socket);
-        exit(EXIT_FAILURE);
+        ssize_t bytes_received = recv(client_socket, buffer, BUFFER_SIZE - 1, 0);
+        if (bytes_received < 0)
+        {
+            perror("recv failed");
+            close(server_socket);
+            exit(EXIT_FAILURE);
+        }
+        #if 0
+        printf("svr recv: %s, len:%d\n", buffer, bytes_received);
+        #endif
+        send(client_socket, buffer, bytes_received, 0);
     }
 
-    printf("Received message from client: %s\n", buffer);
-
     // 关闭套接字
     close(client_socket);
     close(server_socket);
@@ -102,7 +101,7 @@ static int tcp_client(void)
     // 设置服务器地址
     memset(&server_addr, 0, sizeof(server_addr));
     server_addr.sin_family = AF_INET;
-    server_addr.sin_addr.s_addr = inet_addr("192.168.3.10"); // 使用本机IP地址
+    server_addr.sin_addr.s_addr = inet_addr("127.0.0.1"); // 使用本机IP地址
     server_addr.sin_port = htons(PORT);
 
     // 连接到服务器
@@ -115,21 +114,26 @@ static int tcp_client(void)
 
     printf("Connected to server!\n");
 
-    // 发送数据
-    const char *message = "Hello from client!";
-    send(server_socket, message, strlen(message), 0);
-
-    // 接收数据
-    memset(buffer, 0, BUFFER_SIZE);
-    ssize_t bytes_received = recv(server_socket, buffer, BUFFER_SIZE - 1, 0);
-    if (bytes_received < 0)
+    while (1)
     {
-        perror("recv failed");
-        close(server_socket);
-        exit(EXIT_FAILURE);
-    }
+        // 发送数据
+        const char *message = "Hello from client!";
+        send(server_socket, message, strlen(message), 0);
 
-    printf("Received message from server: %s\n", buffer);
+        // 接收数据
+        memset(buffer, 0, BUFFER_SIZE);
+        ssize_t bytes_received = recv(server_socket, buffer, BUFFER_SIZE - 1, 0);
+        if (bytes_received < 0)
+        {
+            perror("recv failed");
+            close(server_socket);
+            exit(EXIT_FAILURE);
+        }
+        #if 0
+        printf("client recv: %s, len:%d\n", buffer, bytes_received);
+        #endif
+        usleep(1000);
+    }
 
     // 关闭套接字
     close(server_socket);
diff --git a/mkrtos_user/user/app/vi/heap_stack.c b/mkrtos_user/user/app/vi/heap_stack.c
index 09a0f7f51..b99946498 100644
--- a/mkrtos_user/user/app/vi/heap_stack.c
+++ b/mkrtos_user/user/app/vi/heap_stack.c
@@ -1,6 +1,6 @@
 
 #define HEAP_SIZE (128*1024)
-#define STACK_SIZE (1024 * 4)
+#define STACK_SIZE (1024 * 3)
 
 #if defined(__CC_ARM)
 #define HEAP_ATTR SECTION("HEAP") __attribute__((zero_init))
diff --git a/mkrtos_user/user/drv/ATSURFF437/block/main.c b/mkrtos_user/user/drv/ATSURFF437/block/main.c
index 6785734a6..d1c4e0182 100644
--- a/mkrtos_user/user/drv/ATSURFF437/block/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/block/main.c
@@ -127,6 +127,6 @@ int main(int argc, char *argv[])
 
     while (1)
     {
-        rpc_loop();
+        u_sleep_ms(0);
     }
 }
diff --git a/mkrtos_user/user/drv/ATSURFF437/display/fs_rpc.c b/mkrtos_user/user/drv/ATSURFF437/display/fs_rpc.c
index e1df1e690..0c2778476 100644
--- a/mkrtos_user/user/drv/ATSURFF437/display/fs_rpc.c
+++ b/mkrtos_user/user/drv/ATSURFF437/display/fs_rpc.c
@@ -333,10 +333,6 @@ int fs_svr_statfs(const char *path, struct statfs *buf)
     return -ENOSYS;
 }
 
-void fs_svr_loop(void)
-{
-    rpc_loop();
-}
 static const fs_operations_t ops =
     {
         .fs_svr_open = fs_svr_open,
diff --git a/mkrtos_user/user/drv/ATSURFF437/display/main.c b/mkrtos_user/user/drv/ATSURFF437/display/main.c
index d05515611..a584fe898 100644
--- a/mkrtos_user/user/drv/ATSURFF437/display/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/display/main.c
@@ -48,6 +48,6 @@ int main(int argc, char *argv[])
     ns_register("/display", hd, FILE_NODE);
     while (1)
     {
-        fs_svr_loop();
+        u_sleep_ms(0);
     }
 }
diff --git a/mkrtos_user/user/drv/ATSURFF437/eth/at_surf_f437_board_emac.c b/mkrtos_user/user/drv/ATSURFF437/eth/at_surf_f437_board_emac.c
index 51c8f7df5..79462e904 100644
--- a/mkrtos_user/user/drv/ATSURFF437/eth/at_surf_f437_board_emac.c
+++ b/mkrtos_user/user/drv/ATSURFF437/eth/at_surf_f437_board_emac.c
@@ -360,7 +360,9 @@ error_status emac_layer2_configuration(void)
   emac_dma_software_reset_set();
 
   while (emac_dma_software_reset_get() == SET)
-    ;
+  {
+    u_sleep_ms(10);
+  }
 
   emac_control_para_init(&mac_control_para);
 
@@ -481,7 +483,7 @@ error_status emac_speed_config(emac_auto_negotiation_type nego, emac_duplex_type
         return ERROR;
       }
       u_sleep_ms(10);
-    } while (!(data & PHY_LINKED_STATUS_BIT) && (timeout < PHY_TIMEOUT));
+    } while (!(data & PHY_LINKED_STATUS_BIT) && (timeout < 100));
 
     if (timeout == PHY_TIMEOUT)
     {
@@ -503,7 +505,7 @@ error_status emac_speed_config(emac_auto_negotiation_type nego, emac_duplex_type
         return ERROR;
       }
       u_sleep_ms(10);
-    } while (!(data & PHY_NEGO_COMPLETE_BIT) && (timeout < PHY_TIMEOUT));
+    } while (!(data & PHY_NEGO_COMPLETE_BIT) && (timeout < 100));
 
     if (timeout == PHY_TIMEOUT)
     {
diff --git a/mkrtos_user/user/drv/ATSURFF437/eth/main.c b/mkrtos_user/user/drv/ATSURFF437/eth/main.c
index edb08021e..43cd252cc 100644
--- a/mkrtos_user/user/drv/ATSURFF437/eth/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/eth/main.c
@@ -102,6 +102,6 @@ int main(int argc, char *argv[])
     meta_reg_svr_obj(&net_drv.svr, BLK_DRV_PROT);
     while (1)
     {
-        rpc_loop();
+        u_sleep_ms(0);
     }
 }
diff --git a/mkrtos_user/user/drv/ATSURFF437/i2c/fs_rpc.c b/mkrtos_user/user/drv/ATSURFF437/i2c/fs_rpc.c
index 723db0aa4..738e60cd8 100644
--- a/mkrtos_user/user/drv/ATSURFF437/i2c/fs_rpc.c
+++ b/mkrtos_user/user/drv/ATSURFF437/i2c/fs_rpc.c
@@ -367,10 +367,6 @@ int fs_svr_statfs(const char *path, struct statfs *buf)
     return -ENOSYS;
 }
 
-void fs_svr_loop(void)
-{
-    rpc_loop();
-}
 static const fs_operations_t ops =
     {
         .fs_svr_open = fs_svr_open,
diff --git a/mkrtos_user/user/drv/ATSURFF437/i2c/main.c b/mkrtos_user/user/drv/ATSURFF437/i2c/main.c
index 36fe8c02f..443ccf740 100644
--- a/mkrtos_user/user/drv/ATSURFF437/i2c/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/i2c/main.c
@@ -49,6 +49,6 @@ int main(int argc, char *argv[])
     ns_register("/i2c2", hd, FILE_NODE);
     while (1)
     {
-        fs_svr_loop();
+        u_sleep_ms(0);
     }
 }
diff --git a/mkrtos_user/user/drv/ATSURFF437/pca9555/fs_rpc.c b/mkrtos_user/user/drv/ATSURFF437/pca9555/fs_rpc.c
index 79eddc6ba..8bbd14bbd 100644
--- a/mkrtos_user/user/drv/ATSURFF437/pca9555/fs_rpc.c
+++ b/mkrtos_user/user/drv/ATSURFF437/pca9555/fs_rpc.c
@@ -373,10 +373,6 @@ int fs_svr_statfs(const char *path, struct statfs *buf)
     return -ENOSYS;
 }
 
-void fs_svr_loop(void)
-{
-    rpc_loop();
-}
 static const fs_operations_t ops =
     {
         .fs_svr_open = fs_svr_open,
diff --git a/mkrtos_user/user/drv/ATSURFF437/pca9555/main.c b/mkrtos_user/user/drv/ATSURFF437/pca9555/main.c
index 5531c03ca..1d8575e05 100644
--- a/mkrtos_user/user/drv/ATSURFF437/pca9555/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/pca9555/main.c
@@ -49,6 +49,6 @@ int main(int argc, char *argv[])
     ns_register("/pca9555", hd, FILE_NODE);
     while (1)
     {
-        fs_svr_loop();
+        u_sleep_ms(0);
     }
 }
diff --git a/mkrtos_user/user/drv/ATSURFF437/pin/fs_rpc.c b/mkrtos_user/user/drv/ATSURFF437/pin/fs_rpc.c
index 69ac3dc23..df235d378 100644
--- a/mkrtos_user/user/drv/ATSURFF437/pin/fs_rpc.c
+++ b/mkrtos_user/user/drv/ATSURFF437/pin/fs_rpc.c
@@ -410,10 +410,6 @@ int fs_svr_statfs(const char *path, struct statfs *buf)
     return -ENOSYS;
 }
 
-void fs_svr_loop(void)
-{
-    rpc_loop();
-}
 static const fs_operations_t ops =
     {
         .fs_svr_open = fs_svr_open,
diff --git a/mkrtos_user/user/drv/ATSURFF437/pin/main.c b/mkrtos_user/user/drv/ATSURFF437/pin/main.c
index 2ec119acc..4c1249288 100644
--- a/mkrtos_user/user/drv/ATSURFF437/pin/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/pin/main.c
@@ -50,6 +50,6 @@ int main(int argc, char *argv[])
     ns_register("/pin", hd, FILE_NODE);
     while (1)
     {
-        fs_svr_loop();
+        u_sleep_ms(0);
     }
 }
diff --git a/mkrtos_user/user/drv/ATSURFF437/snd/main.c b/mkrtos_user/user/drv/ATSURFF437/snd/main.c
index 3c0a00af3..c30a66deb 100644
--- a/mkrtos_user/user/drv/ATSURFF437/snd/main.c
+++ b/mkrtos_user/user/drv/ATSURFF437/snd/main.c
@@ -93,6 +93,6 @@ int main(int argc, char *argv[])
     meta_reg_svr_obj(&snd_drv.svr, BLK_DRV_PROT);
     while (1)
     {
-        rpc_loop();
+        u_sleep_ms(0);
     }
 }