2 files changed, 2 insertions, 2 deletions

diff --git a/firmware/common/ctype.c b/firmware/common/ctype.c
index 5ec0af8add..651dacda86 100644
--- a/firmware/common/ctype.c
+++ b/firmware/common/ctype.c
@@ -1,6 +1,6 @@
 #include <ctype.h>
 
-char    _ctype_[257]={
+const char _ctype_[257]={
         0,
     _C, _C,     _C,     _C,     _C,     _C,     _C,     _C,
         _C,     _C|_S,  _C|_S,  _C|_S,  _C|_S,  _C|_S,  _C,     _C,
diff --git a/firmware/include/ctype.h b/firmware/include/ctype.h
index c72a256e4b..f884b09f81 100644
--- a/firmware/include/ctype.h
+++ b/firmware/include/ctype.h
@@ -39,7 +39,7 @@ int _EXFUN(_toupper, (int __c));
 #ifdef PLUGIN
 #define _ctype_ (rb->_ctype_)
 #else
-extern  char    _ctype_[];
+extern  const char _ctype_[];
 #endif
 
 #ifndef __cplusplus