diff --git a/src/bridge.c b/src/bridge.c
index 0ee0103..5a488e9 100644
--- a/src/bridge.c
+++ b/src/bridge.c
@@ -51,7 +51,7 @@ int parse_ip_data(modem_config *cfg, char *data, int len)
 {
   // I'm going to cheat and assume it comes in chunks.
   int i = 0;
-  char ch;
+  int ch;
   char text[1025];
   int text_len = 0;
 
diff --git a/src/ip232.c b/src/ip232.c
index b0a62fe..07eb181 100644
--- a/src/ip232.c
+++ b/src/ip232.c
@@ -194,7 +194,7 @@ int ip232_read(modem_config *cfg, char *data, int len)
   int rc;
   char buf[256];
   int i = 0;
-  char ch;
+  int ch;
   int text_len = 0;
 
 
diff --git a/src/nvt.c b/src/nvt.c
index bcf319a..67a854c 100644
--- a/src/nvt.c
+++ b/src/nvt.c
@@ -17,7 +17,7 @@ int nvt_init_config(nvt_vars *vars)
   return 0;
 }
 
-char get_nvt_cmd_response(char action, char type)
+int get_nvt_cmd_response(int action, int type)
 {
   char rc = 0;
 
diff --git a/src/nvt.h b/src/nvt.h
index a99ded9..c606417 100644
--- a/src/nvt.h
+++ b/src/nvt.h
@@ -48,7 +48,7 @@ typedef struct nvt_vars {
   char term[256];
 } nvt_vars;
 
-extern char get_nvt_cmd_response(char action, char type);
+extern int get_nvt_cmd_response(int action, int type);
 extern int parse_nvt_subcommand(int fd, nvt_vars *vars, char *data, int len, int speed);
 extern int parse_nvt_command(int fd, nvt_vars *vars, nvtCommand action, nvtOption opt, int parity);
 extern int nvt_init_config(nvt_vars *vars);