diff --git a/esp8266/esp_mphal.c b/esp8266/esp_mphal.c
index 736cf3b0a2a893041ddb39c11746819811a8f7ea..5252e9ce84678b21bbd5641d632a5466d1adb0c1 100644
--- a/esp8266/esp_mphal.c
+++ b/esp8266/esp_mphal.c
@@ -46,7 +46,7 @@ void mp_hal_feed_watchdog(void) {
     //wdt_feed(); // might also work
 }
 
-void mp_hal_udelay(uint32_t us) {
+void mp_hal_delay_us(uint32_t us) {
     ets_delay_us(us);
 }
 
@@ -56,7 +56,7 @@ int mp_hal_stdin_rx_chr(void) {
         if (c != -1) {
             return c;
         }
-        mp_hal_udelay(1);
+        mp_hal_delay_us(1);
         mp_hal_feed_watchdog();
     }
 }
@@ -87,7 +87,7 @@ uint32_t HAL_GetTick(void) {
 }
 
 void HAL_Delay(uint32_t Delay) {
-    mp_hal_udelay(Delay * 1000);
+    mp_hal_delay_us(Delay * 1000);
 }
 
 void mp_hal_set_interrupt_char(int c) {
diff --git a/esp8266/esp_mphal.h b/esp8266/esp_mphal.h
index 617a0f8c1119544833db4027417910dc135797b0..3d64293fd672dab88e6b204e730c7d5f7b42e991 100644
--- a/esp8266/esp_mphal.h
+++ b/esp8266/esp_mphal.h
@@ -32,7 +32,6 @@ void ets_isr_mask(unsigned);
 
 void mp_hal_init(void);
 void mp_hal_feed_watchdog(void);
-void mp_hal_udelay(uint32_t);
 int mp_hal_stdin_rx_chr(void);
 void mp_hal_stdout_tx_str(const char *str);
 void mp_hal_stdout_tx_strn(const char *str, uint32_t len);
@@ -40,6 +39,7 @@ void mp_hal_stdout_tx_strn_cooked(const char *str, uint32_t len);
 
 uint32_t HAL_GetTick(void);
 void HAL_Delay(uint32_t Delay);
+void mp_hal_delay_us(uint32_t);
 void mp_hal_set_interrupt_char(int c);
 uint32_t mp_hal_get_cpu_freq(void);
 
diff --git a/esp8266/main.c b/esp8266/main.c
index 95315dae467057576db2c05647a77f984e045e68..18fd2bd64acd29350ee15b4b85104d9ca315392a 100644
--- a/esp8266/main.c
+++ b/esp8266/main.c
@@ -56,7 +56,7 @@ STATIC void mp_reset(void) {
 
 void soft_reset(void) {
     mp_hal_stdout_tx_str("PYB: soft reset\r\n");
-    mp_hal_udelay(10000); // allow UART to flush output
+    mp_hal_delay_us(10000); // allow UART to flush output
     mp_reset();
     pyexec_event_repl_init();
 }
diff --git a/esp8266/modpyb.c b/esp8266/modpyb.c
index aaa359a93d272075d419ccad8a9c072bb551b473..45096f8cbaa370b620b7e5235a78d5e5c1077cb9 100644
--- a/esp8266/modpyb.c
+++ b/esp8266/modpyb.c
@@ -137,7 +137,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_delay_obj, pyb_delay);
 STATIC mp_obj_t pyb_udelay(mp_obj_t usec_in) {
     mp_int_t usec = mp_obj_get_int(usec_in);
     if (usec >= 0) {
-        mp_hal_udelay(usec);
+        mp_hal_delay_us(usec);
     }
     return mp_const_none;
 }