diff --git a/examples/fmsynth/keyboard_main.c b/examples/fmsynth/keyboard_main.c
index d3f0c9bc4..0cf434a6a 100644
--- a/examples/fmsynth/keyboard_main.c
+++ b/examples/fmsynth/keyboard_main.c
@@ -372,7 +372,7 @@ int main(int argc, FAR char *argv[])
 {
   int i;
   int ret;
-  char key;
+  int key;
   bool running = true;
   pthread_t pid;
   struct app_options appopt;
@@ -416,7 +416,7 @@ int main(int argc, FAR char *argv[])
 
   while (running)
     {
-      key = (char)getchar();
+      key = getchar();
       if (key != EOF)
         {
           switch (key)
diff --git a/examples/fmsynth/mmlplayer_main.c b/examples/fmsynth/mmlplayer_main.c
index edab3cb9a..c5e11f5a0 100644
--- a/examples/fmsynth/mmlplayer_main.c
+++ b/examples/fmsynth/mmlplayer_main.c
@@ -502,7 +502,7 @@ int main(int argc, FAR char *argv[])
 {
   int i;
   int ret;
-  char key;
+  int key;
   bool running = true;
   pthread_t pid;
   struct app_options appopt;
@@ -542,7 +542,7 @@ int main(int argc, FAR char *argv[])
 
   while (running)
     {
-      key = (char)getchar();
+      key = getchar();
       if (key != EOF)
         {
           switch (key)