diff --git a/features/netsocket/emac-drivers/TARGET_ARM_FM/COMPONENT_LAN91C111/fvp_emac.cpp b/features/netsocket/emac-drivers/TARGET_ARM_FM/COMPONENT_LAN91C111/fvp_emac.cpp
index d5e51f453fa..95ec2bf34f0 100644
--- a/features/netsocket/emac-drivers/TARGET_ARM_FM/COMPONENT_LAN91C111/fvp_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_ARM_FM/COMPONENT_LAN91C111/fvp_emac.cpp
@@ -26,6 +26,7 @@
 #include "netsocket/nsapi_types.h"
 #include "mbed_shared_queues.h"
 
+using namespace std::chrono;
 
 /********************************************************************************
  * Internal data
@@ -40,7 +41,7 @@
 /** \brief Driver thread priority */
 #define THREAD_PRIORITY (osPriorityNormal)
 
-#define PHY_TASK_PERIOD_MS      200
+#define PHY_TASK_PERIOD      200ms
 
 
 fvp_EMAC::fvp_EMAC() : _thread(THREAD_PRIORITY, THREAD_STACKSIZE, NULL, "fvp_emac_thread")
@@ -229,7 +230,7 @@ bool fvp_EMAC::power_up()
     /* Allow the PHY task to detect the initial link state and set up the proper flags */
     ThisThread::sleep_for(10);
 
-    _phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD_MS, mbed::callback(this, &fvp_EMAC::phy_task));
+    _phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD, mbed::callback(this, &fvp_EMAC::phy_task));
 
     return true;
 }
diff --git a/features/netsocket/emac-drivers/TARGET_Freescale_EMAC/kinetis_emac.cpp b/features/netsocket/emac-drivers/TARGET_Freescale_EMAC/kinetis_emac.cpp
index 43bf2b45619..ae9f6afb906 100644
--- a/features/netsocket/emac-drivers/TARGET_Freescale_EMAC/kinetis_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_Freescale_EMAC/kinetis_emac.cpp
@@ -48,6 +48,8 @@
 #include "kinetis_emac.h"
 #include "mbed_power_mgmt.h"
 
+using namespace std::chrono;
+
 enet_handle_t g_handle;
 // TX Buffer descriptors
 uint8_t *tx_desc_start_addr;
@@ -75,7 +77,7 @@ extern "C" void kinetis_init_eth_hardware(void);
 /** \brief  Driver thread priority */
 #define THREAD_PRIORITY (osPriorityNormal)
 
-#define PHY_TASK_PERIOD_MS      200
+#define PHY_TASK_PERIOD      200ms
 
 Kinetis_EMAC::Kinetis_EMAC() : xTXDCountSem(ENET_TX_RING_LEN, ENET_TX_RING_LEN), hwaddr()
 {
@@ -507,7 +509,7 @@ bool Kinetis_EMAC::power_up()
     /* Allow the PHY task to detect the initial link state and set up the proper flags */
     osDelay(10);
 
-    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD_MS, mbed::callback(this, &Kinetis_EMAC::phy_task));
+    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD, mbed::callback(this, &Kinetis_EMAC::phy_task));
 
     return true;
 }
diff --git a/features/netsocket/emac-drivers/TARGET_GD_EMAC/gd32xx_emac.cpp b/features/netsocket/emac-drivers/TARGET_GD_EMAC/gd32xx_emac.cpp
index 5ab4a9c4ff9..f08c0410052 100644
--- a/features/netsocket/emac-drivers/TARGET_GD_EMAC/gd32xx_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_GD_EMAC/gd32xx_emac.cpp
@@ -27,6 +27,8 @@
 
 #include "gd32xx_emac.h"
 
+using namespace std::chrono;
+
 /* \brief Flags for worker thread */
 #define _ENET_FLAG_RX                       (1)
 
@@ -34,7 +36,7 @@
 #define _THREAD_STACKSIZE                   (512)
 #define _THREAD_PRIORITY                    (osPriorityHigh)
 
-#define _PHY_TASK_PERIOD_MS                 (200)
+#define _PHY_TASK_PERIOD                    (200ms)
 
 #define _ENET_HW_ADDR_SIZE                  (6)
 #define _ENET_MTU_SIZE                      (1500)
@@ -345,7 +347,7 @@ bool GD32_EMAC::power_up()
     /* Worker thread */
     rx_thread = create_new_thread("gd32_emac_thread", &GD32_EMAC::thread_function, this, _THREAD_STACKSIZE, _THREAD_PRIORITY, &rx_thread_cb);
 
-    phy_task_handle = mbed::mbed_event_queue()->call_every(_PHY_TASK_PERIOD_MS, mbed::callback(this, &GD32_EMAC::phy_task));
+    phy_task_handle = mbed::mbed_event_queue()->call_every(_PHY_TASK_PERIOD, mbed::callback(this, &GD32_EMAC::phy_task));
 
     /* Allow the PHY task to detect the initial link state and set up the proper flags */
     osDelay(10);
diff --git a/features/netsocket/emac-drivers/TARGET_NUVOTON_EMAC/numaker_emac.cpp b/features/netsocket/emac-drivers/TARGET_NUVOTON_EMAC/numaker_emac.cpp
index 32a886af2ee..945583e65b4 100644
--- a/features/netsocket/emac-drivers/TARGET_NUVOTON_EMAC/numaker_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_NUVOTON_EMAC/numaker_emac.cpp
@@ -36,6 +36,8 @@
 #include "numaker_emac.h"
 #include "numaker_eth_hal.h"
 
+using namespace std::chrono;
+
 /********************************************************************************
  *
  ********************************************************************************/
@@ -53,7 +55,7 @@ extern "C" void numaker_eth_rx_next(void);
 /** \brief  Driver thread priority */
 #define THREAD_PRIORITY (osPriorityNormal)
 
-#define PHY_TASK_PERIOD_MS      200
+#define PHY_TASK_PERIOD      200ms
 
 NUMAKER_EMAC::NUMAKER_EMAC() : thread(0), hwaddr()
 {
@@ -331,7 +333,7 @@ bool NUMAKER_EMAC::power_up()
     /* PHY monitoring task */
     phy_state = PHY_UNLINKED_STATE;
 
-    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD_MS, mbed::callback(this, &NUMAKER_EMAC::phy_task));
+    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD, mbed::callback(this, &NUMAKER_EMAC::phy_task));
 
     /* Allow the PHY task to detect the initial link state and set up the proper flags */
     osDelay(10);
diff --git a/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_IMX/imx_emac.cpp b/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_IMX/imx_emac.cpp
index 0db56cb44cf..0077299f835 100644
--- a/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_IMX/imx_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_IMX/imx_emac.cpp
@@ -48,6 +48,8 @@
 #include "imx_emac.h"
 #include "mbed_power_mgmt.h"
 
+using namespace std::chrono;
+
 enet_handle_t g_handle;
 // RX packet buffer pointers
 emac_mem_buf_t *rx_buff[ENET_RX_RING_LEN];
@@ -71,7 +73,7 @@ extern "C" void kinetis_init_eth_hardware(void);
 /** \brief  Driver thread priority */
 #define THREAD_PRIORITY (osPriorityNormal)
 
-#define PHY_TASK_PERIOD_MS      200
+#define PHY_TASK_PERIOD      200ms
 
 Kinetis_EMAC::Kinetis_EMAC() : xTXDCountSem(ENET_TX_RING_LEN, ENET_TX_RING_LEN), hwaddr()
 {
@@ -511,7 +513,7 @@ bool Kinetis_EMAC::power_up()
     /* Allow the PHY task to detect the initial link state and set up the proper flags */
     osDelay(10);
 
-    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD_MS, mbed::callback(this, &Kinetis_EMAC::phy_task));
+    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD, mbed::callback(this, &Kinetis_EMAC::phy_task));
 
     return true;
 }
diff --git a/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_MCU_LPC546XX/lpc546xx_emac.cpp b/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_MCU_LPC546XX/lpc546xx_emac.cpp
index 937e2016a53..4fcffea7d87 100644
--- a/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_MCU_LPC546XX/lpc546xx_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_NXP_EMAC/TARGET_MCU_LPC546XX/lpc546xx_emac.cpp
@@ -31,6 +31,8 @@
 #include "lpc546xx_emac_config.h"
 #include "lpc546xx_emac.h"
 
+using namespace std::chrono;
+
 enet_handle_t g_handle;
 // RX packet buffer pointers
 emac_mem_buf_t *rx_buff[ENET_RX_RING_LEN];
@@ -54,7 +56,7 @@ extern "C" void lpc546xx_init_eth_hardware(void);
 /** \brief  Driver thread priority */
 #define THREAD_PRIORITY (osPriorityNormal)
 
-#define PHY_TASK_PERIOD_MS      200
+#define PHY_TASK_PERIOD      200ms
 
 LPC546XX_EMAC::LPC546XX_EMAC() : xTXDCountSem(ENET_TX_RING_LEN, ENET_TX_RING_LEN), hwaddr()
 {
@@ -497,7 +499,7 @@ bool LPC546XX_EMAC::power_up()
     prev_state.speed = (phy_speed_t)STATE_UNKNOWN;
     prev_state.duplex = (phy_duplex_t)STATE_UNKNOWN;
 
-    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD_MS, mbed::callback(this, &LPC546XX_EMAC::phy_task));
+    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD, mbed::callback(this, &LPC546XX_EMAC::phy_task));
 
     /* Allow the PHY task to detect the initial link state and set up the proper flags */
     osDelay(10);
diff --git a/features/netsocket/emac-drivers/TARGET_STM/stm32xx_emac.cpp b/features/netsocket/emac-drivers/TARGET_STM/stm32xx_emac.cpp
index c3294bd9d4c..98e2eca9945 100644
--- a/features/netsocket/emac-drivers/TARGET_STM/stm32xx_emac.cpp
+++ b/features/netsocket/emac-drivers/TARGET_STM/stm32xx_emac.cpp
@@ -52,13 +52,15 @@
 #include "lwip/api.h"
 #endif
 
+using namespace std::chrono;
+
 /* \brief Flags for worker thread */
 #define FLAG_RX                 1
 
 /** \brief  Driver thread priority */
 #define THREAD_PRIORITY         (osPriorityHigh)
 
-#define PHY_TASK_PERIOD_MS      200
+#define PHY_TASK_PERIOD      200ms
 
 #define STM_HWADDR_SIZE         (6)
 #define STM_ETH_MTU_SIZE        1500
@@ -890,7 +892,7 @@ bool STM32_EMAC::power_up()
 #endif
 
 
-    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD_MS, mbed::callback(this, &STM32_EMAC::phy_task));
+    phy_task_handle = mbed::mbed_event_queue()->call_every(PHY_TASK_PERIOD, mbed::callback(this, &STM32_EMAC::phy_task));
 
 #if defined (STM32F767xx) || defined (STM32F769xx) || defined (STM32F777xx)\
       || defined (STM32F779xx)