diff --git a/driver/src/hw3/board_info_hw.c b/driver/src/hw3/board_info_hw.c
index fcd31c2..9813f8e 100644
--- a/driver/src/hw3/board_info_hw.c
+++ b/driver/src/hw3/board_info_hw.c
@@ -390,7 +390,6 @@ void board_oem_signal_mtx_binding(iot_board_info_v1_t *rc_info)
 
 
 
-extern int32_t sbl_printf(const char *fmt, ...);
 
 
 uint32_t board_load_oem_cfg()
@@ -419,13 +418,10 @@ uint32_t board_load_oem_cfg()
     g_board_cpu_idx = cpu_get_mhartid();
 #endif
 
-    sbl_printf("start load oemcfg\n");
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
     ret = iot_oem_get_cfg(&oemcfg);
     if (ret != ERR_OK) {
         goto out;
     }
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
     g_board_info.board_id = oemcfg->board_id;
     IOT_ASSERT(oemcfg->board_cfg_ver == IOT_OEM_VER_V1);
 
@@ -441,22 +437,18 @@ uint32_t board_load_oem_cfg()
         goto out;
     }
     // 读取oem的差分部分
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
     ret = iot_oem_read_mtd(buf_oem, oem_part_size - oem_diff_offset,
         oem_diff_offset);
     if (ret != ERR_OK) {
         goto out;
     }
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
 
     ret = ERR_FAIL;
     hw_ver_cal = iot_board_hw_version_hex();
     /* if hw_version is not written during production test, it defaults to f */
     if (hw_ver_cal == 0xffffffff) {
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         hw_ver_cal = 0;
     }
-    sbl_printf("board_hw_ver=%08x\n",hw_ver_cal);
     // ptr_rc 是 iot_board_info_v1_t 类型的指针
     ptr_hdr = &ptr_rc->hdr;
     hw_ver_rc = ptr_hdr->hw_version;
@@ -467,7 +459,6 @@ hdr_check:
         if (ptr_hdr->have_next == 0) {
             if(read_oem_ext_flag ||
                 iot_oem_read_mtd_ext(&buf_oem[offset],BOARD_OEM_INFO_SIZE_MAX-offset)){
-                sbl_printf("%s:%d\n",__FILE__,__LINE__);
                 goto out;
             } else {
                 ptr_hdr->have_next = 1;
@@ -483,7 +474,6 @@ hdr_check:
         hw_ver_rc = ptr_hdr->hw_version;
         goto hdr_check;
     }
-    sbl_printf("count_rc=%d\n",cnt_rc);
 
     /* prevent array out of bounds */
     // 最多只支持63个硬件识别码
diff --git a/pib/src/iot_oem.c b/pib/src/iot_oem.c
index 7c61754..d138403 100644
--- a/pib/src/iot_oem.c
+++ b/pib/src/iot_oem.c
@@ -109,15 +109,6 @@ uint32_t iot_oem_read_mtd(uint8_t *buf, uint32_t size, uint32_t offset)
 }
 
 
-extern int32_t sbl_printf(const char *fmt, ...);
-
-
-static void data_printf(const uint8_t *data,int len){
-    for (int i=0;i<len;i++){
-        sbl_printf("%02x ",data[i]);
-    }
-    sbl_printf("\n");
-}
 
 
 
@@ -135,47 +126,32 @@ uint32_t iot_oem_read_mtd_ext(uint8_t *buff,uint32_t buff_size)
     const uint8_t *data;
     const char *oem_ext_magic_str = IOT_OEM_EXT_MAGIC_STR;
     int oem_ext_magic_str_len = strlen(oem_ext_magic_str);
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
 
     do {
         status = dev_get_boot_fw_part_num(&fw_prtition);
         if (status) {
             break;
         }
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         mtd_get_hdr(fw_prtition,&hdr);
         if(hdr.v1.hdrVer!=hdrVer_10){
             break;
         }
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         img_header_construct(&run_fw_hdr,(char *)(hdr.v1.runAddr-HEADER_TOLTAL_SIZE));
-        data_printf((const uint8_t *)&run_fw_hdr,32);
         fw_size=run_fw_hdr.v1.imgSize;
-        sbl_printf("fw_size:%ld\n",fw_size);
         data=(const uint8_t *)(hdr.v1.runAddr+fw_size-oem_ext_magic_str_len);
-        sbl_printf("oem_ext_magic_str_addr:%p\n",data);
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         os_mem_cpy(str_buff,data,oem_ext_magic_str_len);
-        sbl_printf("str_buff:%s\n",str_buff);
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         if(iot_strcmp(str_buff,oem_ext_magic_str) != 0){
             break;
         }
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         data-=4;
         oem_size=((data[0]<<24)|(data[1]<<16)|(data[2]<<8)|data[3]);
-        sbl_printf("oem_size:%ld\n",oem_size);
         data=data-oem_size;
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         if(buff_size<oem_size){
             break;
         }
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         os_mem_cpy(buff,data,oem_size);
-        sbl_printf("%s:%d\n",__FILE__,__LINE__);
         ret = ERR_OK;
     } while(0);
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
     return ret;
 }
 
diff --git a/startup/misc/main.c b/startup/misc/main.c
index d2f878d..e2363da 100644
--- a/startup/misc/main.c
+++ b/startup/misc/main.c
@@ -126,15 +126,12 @@ int32_t iot_module_start(void)
     return 0;
 }
 
-extern int32_t sbl_printf(const char *fmt, ...);
 
 
 uint32_t iot_plc_entry(iot_build_info_t *info)
 {
     sbl_param_input_t param = {0};
 
-    sbl_printf("enter fw...\n");
-
     iot_system_get_fw_boot_param(&param);
     // 设置app的build_info
     iot_version_set_user_build_info(info);
diff --git a/startup/misc/plc/plc_main.c b/startup/misc/plc/plc_main.c
index b65bfab..2dfda11 100644
--- a/startup/misc/plc/plc_main.c
+++ b/startup/misc/plc/plc_main.c
@@ -272,13 +272,11 @@ void iot_mode_set(int fw_mode)
 }
 
 
-extern int32_t sbl_printf(const char *fmt, ...);
 
 
 // 硬件部分初始化
 void iot_hw_init()
 {
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
     // 初始化efuse
     iot_efuse_init();
     // 初始化时钟
@@ -302,14 +300,9 @@ void iot_hw_init()
     // 目前是空函数
     iot_cal_data_init();
 
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
-    write_hw_version(0x0D0A0113);
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
-
 #if (IOT_FLASH_BUILD == 1)
     /* board info config*/
     iot_board_cfg_init();
-    sbl_printf("%s:%d\n",__FILE__,__LINE__);
 #endif
 
     iot_led_init();