diff --git a/demo/env/stm32f10x/non_os/components/easyflash/port/ef_port.c b/demo/env/stm32f10x/non_os/components/easyflash/port/ef_port.c
index 36ae79c..1a12f70 100644
--- a/demo/env/stm32f10x/non_os/components/easyflash/port/ef_port.c
+++ b/demo/env/stm32f10x/non_os/components/easyflash/port/ef_port.c
@@ -71,12 +71,14 @@ EfErrCode ef_port_init(ef_env const **default_env, size_t *default_env_size) {
  */
 EfErrCode ef_port_read(uint32_t addr, uint32_t *buf, size_t size) {
     EfErrCode result = EF_NO_ERR;
+    uint8_t *buf_8 = (uint8_t *)buf;
+    size_t i;
 
-    EF_ASSERT(size % 4 == 0);
+    EF_ASSERT(addr % 4 == 0);
 
     /*copy from flash to ram */
-    for (; size > 0; size -= 4, addr += 4, buf++) {
-        *buf = *(uint32_t *) addr;
+    for (i = 0; i < size; i++, addr ++, buf_8++) {
+        *buf_8 = *(uint8_t *) addr;
     }
 
     return result;
@@ -136,7 +138,7 @@ EfErrCode ef_port_write(uint32_t addr, const uint32_t *buf, size_t size) {
     size_t i;
     uint32_t read_data;
 
-    EF_ASSERT(size % 4 == 0);
+    EF_ASSERT(addr % 4 == 0);
 
     FLASH_Unlock();
     FLASH_ClearFlag(FLASH_FLAG_BSY | FLASH_FLAG_EOP | FLASH_FLAG_PGERR | FLASH_FLAG_WRPRTERR);
diff --git a/demo/env/stm32f10x/rtt/app/src/app_task.c b/demo/env/stm32f10x/rtt/app/src/app_task.c
index e8456df..944f93e 100644
--- a/demo/env/stm32f10x/rtt/app/src/app_task.c
+++ b/demo/env/stm32f10x/rtt/app/src/app_task.c
@@ -112,7 +112,7 @@ int rt_application_init(void)
     rt_thread_startup(&thread_sys_monitor);
 
     init_thread = rt_thread_create("sys init", sys_init_thread,
-            NULL, 512, 10, 10);
+            NULL, 1024, 10, 10);
     if (init_thread != NULL) {
         rt_thread_startup(init_thread);
     }
diff --git a/demo/env/stm32f10x/rtt/components/easyflash/port/ef_port.c b/demo/env/stm32f10x/rtt/components/easyflash/port/ef_port.c
index 0729666..2f404be 100644
--- a/demo/env/stm32f10x/rtt/components/easyflash/port/ef_port.c
+++ b/demo/env/stm32f10x/rtt/components/easyflash/port/ef_port.c
@@ -74,12 +74,14 @@ EfErrCode ef_port_init(ef_env const **default_env, size_t *default_env_size) {
  */
 EfErrCode ef_port_read(uint32_t addr, uint32_t *buf, size_t size) {
     EfErrCode result = EF_NO_ERR;
+    uint8_t *buf_8 = (uint8_t *)buf;
+    size_t i;
 
-    EF_ASSERT(size % 4 == 0);
+    EF_ASSERT(addr % 4 == 0);
 
     /*copy from flash to ram */
-    for (; size > 0; size -= 4, addr += 4, buf++) {
-        *buf = *(uint32_t *) addr;
+    for (i = 0; i < size; i++, addr ++, buf_8++) {
+        *buf_8 = *(uint8_t *) addr;
     }
 
     return result;
@@ -139,7 +141,7 @@ EfErrCode ef_port_write(uint32_t addr, const uint32_t *buf, size_t size) {
     size_t i;
     uint32_t read_data;
 
-    EF_ASSERT(size % 4 == 0);
+    EF_ASSERT(addr % 4 == 0);
 
     FLASH_Unlock();
     FLASH_ClearFlag(FLASH_FLAG_BSY | FLASH_FLAG_EOP | FLASH_FLAG_PGERR | FLASH_FLAG_WRPRTERR);