Aircon: Do not crash on receiving 0x00 on debug USART

This happens during initialization if the debug port is not connected.

diff --git a/aircon/firmware/main.c b/aircon/firmware/main.c
index c43012162caa840a9e01da1c7958b17017bc8fcb..129ac71fbe8e35e5ceb66e5ee001369b7aa6a063 100644 (file)
--- a/aircon/firmware/main.c
+++ b/aircon/firmware/main.c
@@ -347,6 +347,8 @@ static bool rc_send(char key)
 {
        if (rc_pending)
                return false;
+       if (!key)
+               return false;
 
        const char *s = strchr(rc_keys, key);
        if (!s)