From 87d5c0cad2031f23d9ce6b80536a152b44b2ae7f Mon Sep 17 00:00:00 2001
From: alanbjohnston <alan.b.johnston@gmail.com>
Date: Wed, 17 Aug 2022 06:40:17 -0400
Subject: [PATCH] only update callsign if length > 0

---
 cubesatsim/cubesatsim.ino | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/cubesatsim/cubesatsim.ino b/cubesatsim/cubesatsim.ino
index fb58a4f3..8dfd83d4 100644
--- a/cubesatsim/cubesatsim.ino
+++ b/cubesatsim/cubesatsim.ino
@@ -3729,10 +3729,13 @@ void prompt_for_input() {
       Serial.print("Enter callsign in all capitals: ");
       get_serial_string();
 		  
-      print_string(serial_string);		  
+      print_string(serial_string);
 		  
-      strcpy(callsign, serial_string);
-      Serial.println("Callsign updated!");	 	  
+      if (strlen(callsign) > 0)	{	  
+        strcpy(callsign, serial_string);
+        Serial.println("Callsign updated!");
+      } else
+        Serial.println("Callsign not updated!");	      
 /*
 	echo	
 	echo "Editing the CALLSIGN in the"