diff --git a/cc3200/mods/pybrtc.c b/cc3200/mods/pybrtc.c
index d57e11167..a9cc995d5 100644
--- a/cc3200/mods/pybrtc.c
+++ b/cc3200/mods/pybrtc.c
@@ -210,7 +210,7 @@ STATIC mp_obj_t pyb_rtc_callback (mp_uint_t n_args, const mp_obj_t *pos_args, mp
         // set the match value
         MAP_PRCMRTCMatchSet(seconds, mseconds);
 
-        // save the match data for later
+        // save the power mode data for later
         pybrtc_data.prwmode = args[4].u_int;
 
         // create the callback
diff --git a/cc3200/mods/pybuart.c b/cc3200/mods/pybuart.c
index 9465cef08..8d1f79b03 100644
--- a/cc3200/mods/pybuart.c
+++ b/cc3200/mods/pybuart.c
@@ -516,7 +516,7 @@ STATIC mp_obj_t pyb_uart_callback (mp_uint_t n_args, const mp_obj_t *pos_args, m
         uint priority = mpcallback_translate_priority (args[2].u_int);
 
         // check the power mode
-        if (PYB_PWR_MODE_ACTIVE != args[3].u_int) {
+        if (PYB_PWR_MODE_ACTIVE != args[4].u_int) {
             nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, mpexception_value_invalid_arguments));
         }