diff --git a/components/bt/bluedroid/btc/core/btc_task.c b/components/bt/bluedroid/btc/core/btc_task.c
index b4ce0d95ca..773d7889bb 100644
--- a/components/bt/bluedroid/btc/core/btc_task.c
+++ b/components/bt/bluedroid/btc/core/btc_task.c
@@ -80,7 +80,7 @@ static bt_status_t btc_task_post(btc_msg_t *msg)
         return BT_STATUS_PARM_INVALID;
     }
 
-    if (xQueueSend(xBtcQueue, msg, 10 / portTICK_RATE_MS) != pdTRUE) {
+    if (xQueueSend(xBtcQueue, msg, 10 / portTICK_PERIOD_MS) != pdTRUE) {
         LOG_ERROR("Btc Post failed\n");
         return BT_STATUS_BUSY;
     }
diff --git a/components/bt/bluedroid/hci/hci_hal_h4.c b/components/bt/bluedroid/hci/hci_hal_h4.c
index 922ee6ecc0..237226266a 100644
--- a/components/bt/bluedroid/hci/hci_hal_h4.c
+++ b/components/bt/bluedroid/hci/hci_hal_h4.c
@@ -177,7 +177,7 @@ void hci_hal_h4_task_post(void)
     evt.sig = 0xff;
     evt.par = 0;
 
-    if (xQueueSend(xHciH4Queue, &evt, 10 / portTICK_RATE_MS) != pdTRUE) {
+    if (xQueueSend(xHciH4Queue, &evt, 10 / portTICK_PERIOD_MS) != pdTRUE) {
         LOG_ERROR("xHciH4Queue failed\n");
     }
 }
diff --git a/components/bt/bluedroid/hci/hci_layer.c b/components/bt/bluedroid/hci/hci_layer.c
index e0f15e0ea9..d71690d4a6 100644
--- a/components/bt/bluedroid/hci/hci_layer.c
+++ b/components/bt/bluedroid/hci/hci_layer.c
@@ -146,7 +146,7 @@ void hci_host_task_post(void)
     evt.sig = 0xff;
     evt.par = 0;
 
-    if (xQueueSend(xHciHostQueue, &evt, 10 / portTICK_RATE_MS) != pdTRUE) {
+    if (xQueueSend(xHciHostQueue, &evt, 10 / portTICK_PERIOD_MS) != pdTRUE) {
         LOG_ERROR("xHciHostQueue failed\n");
     }
 }
diff --git a/components/bt/bluedroid/osi/osi_arch.c b/components/bt/bluedroid/osi/osi_arch.c
index e896efd871..d1d0185aec 100644
--- a/components/bt/bluedroid/osi/osi_arch.c
+++ b/components/bt/bluedroid/osi/osi_arch.c
@@ -137,9 +137,9 @@ osi_sem_wait(osi_sem_t *sem, uint32_t timeout)
     StartTime = xTaskGetTickCount();
 
     if (timeout != 0) {
-        if (xSemaphoreTake(*sem, timeout / portTICK_RATE_MS) == pdTRUE) {
+        if (xSemaphoreTake(*sem, timeout / portTICK_PERIOD_MS) == pdTRUE) {
             EndTime = xTaskGetTickCount();
-            Elapsed = (EndTime - StartTime) * portTICK_RATE_MS;
+            Elapsed = (EndTime - StartTime) * portTICK_PERIOD_MS;
 
             if (Elapsed == 0) {
                 Elapsed = 1;
@@ -153,7 +153,7 @@ osi_sem_wait(osi_sem_t *sem, uint32_t timeout)
         while (xSemaphoreTake(*sem, portMAX_DELAY) != pdTRUE);
 
         EndTime = xTaskGetTickCount();
-        Elapsed = (EndTime - StartTime) * portTICK_RATE_MS;
+        Elapsed = (EndTime - StartTime) * portTICK_PERIOD_MS;
 
         if (Elapsed == 0) {
             Elapsed = 1;
@@ -190,7 +190,7 @@ osi_now(void)
 
 void osi_delay_ms(uint32_t ms)
 {
-    vTaskDelay(ms / portTICK_RATE_MS);
+    vTaskDelay(ms / portTICK_PERIOD_MS);
 }
 
 
diff --git a/components/bt/bluedroid/stack/btu/btu_task.c b/components/bt/bluedroid/stack/btu/btu_task.c
index 5cca29dd83..4c640fad7c 100644
--- a/components/bt/bluedroid/stack/btu/btu_task.c
+++ b/components/bt/bluedroid/stack/btu/btu_task.c
@@ -338,7 +338,7 @@ void btu_task_post(uint32_t sig)
     evt.sig = sig;
     evt.par = 0;
 
-    if (xQueueSend(xBtuQueue, &evt, 10 / portTICK_RATE_MS) != pdTRUE) {
+    if (xQueueSend(xBtuQueue, &evt, 10 / portTICK_PERIOD_MS) != pdTRUE) {
         LOG_ERROR("xBtuQueue failed\n");
     }
 }
diff --git a/components/bt/bt.c b/components/bt/bt.c
index ef9a063d69..8d1fecb777 100644
--- a/components/bt/bt.c
+++ b/components/bt/bt.c
@@ -85,7 +85,7 @@ static int32_t IRAM_ATTR semphr_give_from_isr_wrapper(void *semphr, void *hptw)
 
 static int32_t IRAM_ATTR semphr_take_wrapper(void *semphr, uint32_t block_time_ms)
 {
-    return (int32_t)xSemaphoreTake(semphr, block_time_ms / portTICK_RATE_MS);
+    return (int32_t)xSemaphoreTake(semphr, block_time_ms / portTICK_PERIOD_MS);
 }
 
 static void *IRAM_ATTR mutex_create_wrapper(void)
diff --git a/components/esp32/test/test_intr_alloc.c b/components/esp32/test/test_intr_alloc.c
index 31991b4e41..329fc9a9e4 100644
--- a/components/esp32/test/test_intr_alloc.c
+++ b/components/esp32/test/test_intr_alloc.c
@@ -98,7 +98,7 @@ static void timer_test(int flags) {
             esp_intr_get_intno(inth[0]), esp_intr_get_intno(inth[1]),
             esp_intr_get_intno(inth[2]), esp_intr_get_intno(inth[3]));
     printf("Timer values on start: %d %d %d %d\n", count[0], count[1], count[2], count[3]);
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer values after 1 sec: %d %d %d %d\n", count[0], count[1], count[2], count[3]);
     TEST_ASSERT(count[0]==0);
     TEST_ASSERT(count[1]!=0);
@@ -110,7 +110,7 @@ static void timer_test(int flags) {
     esp_intr_disable(inth[1]);
     esp_intr_disable(inth[2]);
     for (x=0; x<4; x++) count[x]=0;
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer values after 1 sec: %d %d %d %d\n", count[0], count[1], count[2], count[3]);
     TEST_ASSERT(count[0]!=0);
     TEST_ASSERT(count[1]==0);
@@ -122,7 +122,7 @@ static void timer_test(int flags) {
     esp_intr_disable(inth[0]);
     esp_intr_disable(inth[3]);
     for (x=0; x<4; x++) count[x]=0;
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer values after 1 sec: %d %d %d %d\n", count[0], count[1], count[2], count[3]);
     TEST_ASSERT(count[0]==0);
     TEST_ASSERT(count[1]!=0);
@@ -152,18 +152,18 @@ void local_timer_test()
     printf("Int timer 1 intno %d\n", esp_intr_get_intno(ih));
     xthal_set_ccompare(1, xthal_get_ccount()+8000000);
     int_timer_ctr=0;
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer val after 1 sec: %d\n", int_timer_ctr);
     TEST_ASSERT(int_timer_ctr!=0);
     printf("Disabling int\n");
     esp_intr_disable(ih);
     int_timer_ctr=0;
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer val after 1 sec: %d\n", int_timer_ctr);
     TEST_ASSERT(int_timer_ctr==0);
     printf("Re-enabling\n");
     esp_intr_enable(ih);
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer val after 1 sec: %d\n", int_timer_ctr);
     TEST_ASSERT(int_timer_ctr!=0);
 
@@ -173,12 +173,12 @@ void local_timer_test()
     r=esp_intr_alloc(ETS_INTERNAL_TIMER1_INTR_SOURCE, ESP_INTR_FLAG_INTRDISABLED, int_timer_handler, NULL, &ih);
     TEST_ASSERT(r==ESP_OK);
     int_timer_ctr=0;
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer val after 1 sec: %d\n", int_timer_ctr);
     TEST_ASSERT(int_timer_ctr==0);
     printf("Re-enabling\n");
     esp_intr_enable(ih);
-    vTaskDelay(1000 / portTICK_RATE_MS);
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
     printf("Timer val after 1 sec: %d\n", int_timer_ctr);
     TEST_ASSERT(int_timer_ctr!=0);
     r=esp_intr_free(ih);
diff --git a/components/ethernet/emac_main.c b/components/ethernet/emac_main.c
index ab2ca8964c..20d428cf7b 100644
--- a/components/ethernet/emac_main.c
+++ b/components/ethernet/emac_main.c
@@ -585,7 +585,7 @@ void emac_link_check_func(void *pv_parameters)
 
 static bool emac_link_check_timer_init(void)
 {
-    emac_timer = xTimerCreate("emac_timer", (2000 / portTICK_RATE_MS),
+    emac_timer = xTimerCreate("emac_timer", (2000 / portTICK_PERIOD_MS),
                               pdTRUE, (void *)rand(), emac_link_check_func);
     if (emac_timer == NULL) {
         return false;
@@ -844,7 +844,7 @@ esp_err_t IRAM_ATTR emac_post(emac_sig_t sig, emac_par_t par)
         evt.sig = sig;
         evt.par = par;
 
-        if (xQueueSend(emac_xqueue, &evt, 10 / portTICK_RATE_MS) != pdTRUE) {
+        if (xQueueSend(emac_xqueue, &evt, 10 / portTICK_PERIOD_MS) != pdTRUE) {
             return ESP_FAIL;
         }
     }
diff --git a/components/freertos/test/test_freertos_eventgroups.c b/components/freertos/test/test_freertos_eventgroups.c
index 35a5cc4ed2..b17e127c28 100644
--- a/components/freertos/test/test_freertos_eventgroups.c
+++ b/components/freertos/test/test_freertos_eventgroups.c
@@ -34,7 +34,7 @@ static void task_event_group_call_response(void *param)
     printf("Task %d done\n", task_num);
 
     /* Delay is due to not-yet-fixed bug with deleting tasks at same time */
-    vTaskDelay(100 / portTICK_RATE_MS);
+    vTaskDelay(100 / portTICK_PERIOD_MS);
     vTaskDelete(NULL);
 }
 
@@ -85,7 +85,7 @@ static void task_test_sync(void *param)
     printf("Done %d = %x\n", task_num, after_done);
 
     /* Delay is due to not-yet-fixed bug with deleting tasks at same time */
-    vTaskDelay(100 / portTICK_RATE_MS);
+    vTaskDelay(100 / portTICK_PERIOD_MS);
     vTaskDelete(NULL);
 }
 
diff --git a/components/lwip/port/freertos/sys_arch.c b/components/lwip/port/freertos/sys_arch.c
index 97ee32d1bd..7f96c9b859 100755
--- a/components/lwip/port/freertos/sys_arch.c
+++ b/components/lwip/port/freertos/sys_arch.c
@@ -164,9 +164,9 @@ sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout)
   StartTime = xTaskGetTickCount();
 
   if (timeout != 0) {
-    if (xSemaphoreTake(*sem, timeout / portTICK_RATE_MS) == pdTRUE) {
+    if (xSemaphoreTake(*sem, timeout / portTICK_PERIOD_MS) == pdTRUE) {
       EndTime = xTaskGetTickCount();
-      Elapsed = (EndTime - StartTime) * portTICK_RATE_MS;
+      Elapsed = (EndTime - StartTime) * portTICK_PERIOD_MS;
 
       if (Elapsed == 0) {
         Elapsed = 1;
@@ -180,7 +180,7 @@ sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout)
     while (xSemaphoreTake(*sem, portMAX_DELAY) != pdTRUE);
 
     EndTime = xTaskGetTickCount();
-    Elapsed = (EndTime - StartTime) * portTICK_RATE_MS;
+    Elapsed = (EndTime - StartTime) * portTICK_PERIOD_MS;
 
     if (Elapsed == 0) {
       Elapsed = 1;
@@ -293,9 +293,9 @@ sys_arch_mbox_fetch(sys_mbox_t *mbox, void **msg, u32_t timeout)
   sys_mutex_lock(&(*mbox)->lock);
 
   if (timeout != 0) {
-    if (pdTRUE == xQueueReceive((*mbox)->os_mbox, &(*msg), timeout / portTICK_RATE_MS)) {
+    if (pdTRUE == xQueueReceive((*mbox)->os_mbox, &(*msg), timeout / portTICK_PERIOD_MS)) {
       EndTime = xTaskGetTickCount();
-      Elapsed = (EndTime - StartTime) * portTICK_RATE_MS;
+      Elapsed = (EndTime - StartTime) * portTICK_PERIOD_MS;
 
       if (Elapsed == 0) {
         Elapsed = 1;
@@ -323,7 +323,7 @@ sys_arch_mbox_fetch(sys_mbox_t *mbox, void **msg, u32_t timeout)
     }
 
     EndTime = xTaskGetTickCount();
-    Elapsed = (EndTime - StartTime) * portTICK_RATE_MS;
+    Elapsed = (EndTime - StartTime) * portTICK_PERIOD_MS;
 
     if (Elapsed == 0) {
       Elapsed = 1;
@@ -566,7 +566,7 @@ void sys_thread_sem_deinit(void)
 
 void sys_delay_ms(uint32_t ms)
 {
-  vTaskDelay(ms/portTICK_RATE_MS);
+  vTaskDelay(ms / portTICK_PERIOD_MS);
 }
 
 
diff --git a/examples/01_hello_world/main/hello_world_main.c b/examples/01_hello_world/main/hello_world_main.c
index 0e872522fa..c8b9f5f0c9 100644
--- a/examples/01_hello_world/main/hello_world_main.c
+++ b/examples/01_hello_world/main/hello_world_main.c
@@ -17,7 +17,7 @@ void hello_task(void *pvParameter)
     printf("Hello world!\n");
     for (int i = 10; i >= 0; i--) {
         printf("Restarting in %d seconds...\n", i);
-        vTaskDelay(1000 / portTICK_RATE_MS);
+        vTaskDelay(1000 / portTICK_PERIOD_MS);
     }
     printf("Restarting now.\n");
     fflush(stdout);
diff --git a/examples/02_blink/main/blink.c b/examples/02_blink/main/blink.c
index 1e49e51b2f..f97572ac21 100644
--- a/examples/02_blink/main/blink.c
+++ b/examples/02_blink/main/blink.c
@@ -33,10 +33,10 @@ void blink_task(void *pvParameter)
     while(1) {
         /* Blink off (output low) */
         gpio_set_level(BLINK_GPIO, 0);
-        vTaskDelay(1000 / portTICK_RATE_MS);
+        vTaskDelay(1000 / portTICK_PERIOD_MS);
         /* Blink on (output high) */
         gpio_set_level(BLINK_GPIO, 1);
-        vTaskDelay(1000 / portTICK_RATE_MS);
+        vTaskDelay(1000 / portTICK_PERIOD_MS);
     }
 }
 
diff --git a/examples/03_http_request/main/http_request_main.c b/examples/03_http_request/main/http_request_main.c
index 9fe1933373..3831ae65b9 100644
--- a/examples/03_http_request/main/http_request_main.c
+++ b/examples/03_http_request/main/http_request_main.c
@@ -115,7 +115,7 @@ static void http_get_task(void *pvParameters)
 
         if(err != 0 || res == NULL) {
             ESP_LOGE(TAG, "DNS lookup failed err=%d res=%p", err, res);
-            vTaskDelay(1000 / portTICK_RATE_MS);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
             continue;
         }
 
@@ -129,7 +129,7 @@ static void http_get_task(void *pvParameters)
         if(s < 0) {
             ESP_LOGE(TAG, "... Failed to allocate socket.");
             freeaddrinfo(res);
-            vTaskDelay(1000 / portTICK_RATE_MS);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
             continue;
         }
         ESP_LOGI(TAG, "... allocated socket\r\n");
@@ -138,7 +138,7 @@ static void http_get_task(void *pvParameters)
             ESP_LOGE(TAG, "... socket connect failed errno=%d", errno);
             close(s);
             freeaddrinfo(res);
-            vTaskDelay(4000 / portTICK_RATE_MS);
+            vTaskDelay(4000 / portTICK_PERIOD_MS);
             continue;
         }
 
@@ -148,7 +148,7 @@ static void http_get_task(void *pvParameters)
         if (write(s, REQUEST, strlen(REQUEST)) < 0) {
             ESP_LOGE(TAG, "... socket send failed");
             close(s);
-            vTaskDelay(4000 / portTICK_RATE_MS);
+            vTaskDelay(4000 / portTICK_PERIOD_MS);
             continue;
         }
         ESP_LOGI(TAG, "... socket send success");
@@ -166,7 +166,7 @@ static void http_get_task(void *pvParameters)
         close(s);
         for(int countdown = 10; countdown >= 0; countdown--) {
             ESP_LOGI(TAG, "%d... ", countdown);
-            vTaskDelay(1000 / portTICK_RATE_MS);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
         }
         ESP_LOGI(TAG, "Starting again!");
     }
diff --git a/examples/04_https_request/main/https_request_main.c b/examples/04_https_request/main/https_request_main.c
index caf3f374a3..933d97ac83 100644
--- a/examples/04_https_request/main/https_request_main.c
+++ b/examples/04_https_request/main/https_request_main.c
@@ -362,7 +362,7 @@ static void https_get_task(void *pvParameters)
 
         for(int countdown = 10; countdown >= 0; countdown--) {
             ESP_LOGI(TAG, "%d...", countdown);
-            vTaskDelay(1000 / portTICK_RATE_MS);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
         }
         ESP_LOGI(TAG, "Starting again!");
     }
diff --git a/examples/07_nvs_rw_value/main/nvs_rw_value.c b/examples/07_nvs_rw_value/main/nvs_rw_value.c
index dac2d4077e..1b3e06b859 100644
--- a/examples/07_nvs_rw_value/main/nvs_rw_value.c
+++ b/examples/07_nvs_rw_value/main/nvs_rw_value.c
@@ -72,7 +72,7 @@ void app_main()
     // Restart module
     for (int i = 10; i >= 0; i--) {
         printf("Restarting in %d seconds...\n", i);
-        vTaskDelay(1000 / portTICK_RATE_MS);
+        vTaskDelay(1000 / portTICK_PERIOD_MS);
     }
     printf("Restarting now.\n");
     fflush(stdout);
diff --git a/examples/08_nvs_rw_blob/main/nvs_rw_blob.c b/examples/08_nvs_rw_blob/main/nvs_rw_blob.c
index 7c13c15ba7..0d4b7db4ee 100644
--- a/examples/08_nvs_rw_blob/main/nvs_rw_blob.c
+++ b/examples/08_nvs_rw_blob/main/nvs_rw_blob.c
@@ -164,7 +164,7 @@ void app_main()
      */
     while (1) {
         if (gpio_get_level(GPIO_NUM_0) == 0) {
-            vTaskDelay(1000 / portTICK_RATE_MS);
+            vTaskDelay(1000 / portTICK_PERIOD_MS);
             if(gpio_get_level(GPIO_NUM_0) == 0) {
                 err = save_run_time();
                 if (err != ESP_OK) printf("Error (%d) saving run time blob to NVS!\n", err);
@@ -173,6 +173,6 @@ void app_main()
                 esp_restart();
             }
         }
-        vTaskDelay(200 / portTICK_RATE_MS);
+        vTaskDelay(200 / portTICK_PERIOD_MS);
     }
 }
diff --git a/examples/11_rmt_nec_tx_rx/main/infrared_nec.c b/examples/11_rmt_nec_tx_rx/main/infrared_nec.c
index d2f7b091fa..ea42502749 100644
--- a/examples/11_rmt_nec_tx_rx/main/infrared_nec.c
+++ b/examples/11_rmt_nec_tx_rx/main/infrared_nec.c
@@ -352,7 +352,7 @@ void rmt_nec_tx_task()
         rmt_wait_tx_done(channel);
         //before we free the data, make sure sending is already done.
         free(item);
-        vTaskDelay(2000 / portTICK_RATE_MS);
+        vTaskDelay(2000 / portTICK_PERIOD_MS);
     }
     vTaskDelete(NULL);
 }
diff --git a/examples/12_blufi/components/blufi/blufi_task.c b/examples/12_blufi/components/blufi/blufi_task.c
index cda66c0511..75547c6432 100644
--- a/examples/12_blufi/components/blufi/blufi_task.c
+++ b/examples/12_blufi/components/blufi/blufi_task.c
@@ -69,7 +69,7 @@ static esp_err_t blufi_task_post(uint32_t sig, void *par, void *cb, void *arg)
     evt.cb = cb;
     evt.arg = arg;
 
-    if (xQueueSend(xBlufiTaskQueue, &evt, 10 / portTICK_RATE_MS) != pdTRUE) {
+    if (xQueueSend(xBlufiTaskQueue, &evt, 10 / portTICK_PERIOD_MS) != pdTRUE) {
         LOG_ERROR("Blufi Post failed\n");
         return ESP_FAIL;
     }
diff --git a/examples/16_pcnt/main/pcnt_test.c b/examples/16_pcnt/main/pcnt_test.c
index b8489ecb2f..0185f9b6f9 100644
--- a/examples/16_pcnt/main/pcnt_test.c
+++ b/examples/16_pcnt/main/pcnt_test.c
@@ -196,7 +196,7 @@ void app_main()
     portBASE_TYPE res;
     while(1)
     {
-        res = xQueueReceive(pcnt_evt_queue, &evt, 1000 / portTICK_RATE_MS);
+        res = xQueueReceive(pcnt_evt_queue, &evt, 1000 / portTICK_PERIOD_MS);
         if(res == pdTRUE) {
             pcnt_get_counter_value(PCNT_TEST_UNIT, &count);
             printf("Event PCNT unit[%d]; cnt: %d\n", evt.unit, count);
diff --git a/examples/17_ethernet/main/ethernet_main.c b/examples/17_ethernet/main/ethernet_main.c
index 7e84a9badd..fc4347f7d8 100644
--- a/examples/17_ethernet/main/ethernet_main.c
+++ b/examples/17_ethernet/main/ethernet_main.c
@@ -108,11 +108,11 @@ void eth_task(void *pvParameter)
 {
     tcpip_adapter_ip_info_t ip;
     memset(&ip, 0, sizeof(tcpip_adapter_ip_info_t));
-    vTaskDelay(2000 / portTICK_RATE_MS);
+    vTaskDelay(2000 / portTICK_PERIOD_MS);
 
     while (1) {
 
-        vTaskDelay(2000 / portTICK_RATE_MS);
+        vTaskDelay(2000 / portTICK_PERIOD_MS);
 
         if (tcpip_adapter_get_ip_info(ESP_IF_ETH, &ip) == 0) {
             ESP_LOGI(TAG, "\n~~~~~~~~~~~\n");
diff --git a/examples/19_sigmadelta/main/sigmadelta_test.c b/examples/19_sigmadelta/main/sigmadelta_test.c
index 92bc6e0a83..60880311d5 100644
--- a/examples/19_sigmadelta/main/sigmadelta_test.c
+++ b/examples/19_sigmadelta/main/sigmadelta_test.c
@@ -46,7 +46,7 @@ void app_main()
     while(1) {
         sigmadelta_set_duty(SIGMADELTA_CHANNEL_0, duty);
         /*by changing delay time, you can change the blink frequency of LED. */
-        vTaskDelay(10 / portTICK_RATE_MS);
+        vTaskDelay(10 / portTICK_PERIOD_MS);
 
         duty += inc;
         if(duty == 127 || duty == -127) inc = (-1) * inc;