diff --git a/qemu-char.c b/qemu-char.c
index 88f4025..242b799 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -134,9 +134,9 @@ static void qemu_chr_fire_open_event(void *opaque)
 void qemu_chr_generic_open(CharDriverState *s)
 {
     if (s->open_timer == NULL) {
-        s->open_timer = qemu_new_timer_ms(vm_clock,
+        s->open_timer = qemu_new_timer_ms(rt_clock,
                                           qemu_chr_fire_open_event, s);
-        qemu_mod_timer(s->open_timer, qemu_get_clock_ms(vm_clock) - 1);
+        qemu_mod_timer(s->open_timer, qemu_get_clock_ms(rt_clock) - 1);
     }
 }