diff --git a/ports/unix/unix_mphal.c b/ports/unix/unix_mphal.c
index 5f5abc2e05..39311c9872 100644
--- a/ports/unix/unix_mphal.c
+++ b/ports/unix/unix_mphal.c
@@ -242,9 +242,13 @@ uint64_t mp_hal_time_ns(void) {
 
 #ifndef mp_hal_delay_ms
 void mp_hal_delay_ms(mp_uint_t ms) {
-    mp_uint_t start = mp_hal_ticks_ms();
-    while (mp_hal_ticks_ms() - start < ms) {
-        mp_event_wait_ms(1);
+    if (ms) {
+        mp_uint_t start = mp_hal_ticks_ms();
+        while (mp_hal_ticks_ms() - start < ms) {
+            mp_event_wait_ms(1);
+        }
+    } else {
+        mp_handle_pending(true);
     }
 }
 #endif