diff --git a/Core/Src/sts_cmox_hmac_sha.c b/Core/Src/sts_cmox_hmac_sha.c
index 51c32b5..390ef34 100644
--- a/Core/Src/sts_cmox_hmac_sha.c
+++ b/Core/Src/sts_cmox_hmac_sha.c
@@ -40,7 +40,7 @@ uint32_t sts_hmac_verify(void)
 	hmac_result.ac_pass = 60;
 	hmac_result.hmac_tag_size = 0;
 	GetUniqueId(uid);
-	APP_LOG(TS_OFF, VLEVEL_M, "\r\nUID=%02x %02x %02x %02x\r\n",uid[4],uid[5],uid[6],uid[7]);
+
 	ret = sts_hmac_sha1((const uint8_t *) mKey, sizeof(mKey), (const uint8_t*)(uid+4), 4, &hmac_result);
 	for (i=0;i<sizeof(Computed_Tag_SHA1); i++) {
 			APP_LOG(TS_OFF,VLEVEL_M,"0x%02x ", hmac_result.hmac_tag[i]);
@@ -50,12 +50,12 @@ uint32_t sts_hmac_verify(void)
 
 	if (ret !=0)
 	{
-		hmac_result.ac_pass  =0;
+		hmac_result.ac_pass  =0U;
 		APP_LOG(TS_OFF, VLEVEL_M, "\r\nHMAC Verify Error \r\n");
 	} else
 	{
 		ret =0;
-		hmac_result.ac_pass = 1;
+		hmac_result.ac_pass = 1U;
 		APP_LOG(TS_OFF, VLEVEL_M, "\r\nHMAC Verify Success\r\n");
 	}
 	return ret;
diff --git a/LoRaWAN/App/lora_app.c b/LoRaWAN/App/lora_app.c
index 8beb7ca..5583b75 100644
--- a/LoRaWAN/App/lora_app.c
+++ b/LoRaWAN/App/lora_app.c
@@ -48,7 +48,7 @@
 /* USER CODE BEGIN EV */
 extern volatile uint8_t sts_service_mask;
 extern volatile uint32_t rfac_timer;
-volatile uint8_t sts_ac_code[YUNHORN_STS_AC_CODE_SIZE]="";
+volatile uint8_t sts_ac_code[YUNHORN_STS_AC_CODE_SIZE]={0x0};
 extern hmac_result_t hmac_result;
 volatile uint8_t sts_work_mode =0;
 //volatile uint32_t SamplingPeriodicity = 15000; 		//unit ms