diff --git a/site_ansto/hardsup/Monitor/device.c b/site_ansto/hardsup/Monitor/device.c
index 2b7c9e9d..4ba741fe 100644
--- a/site_ansto/hardsup/Monitor/device.c
+++ b/site_ansto/hardsup/Monitor/device.c
@@ -368,7 +368,7 @@ int device_command(void* counter, const char* command)
   return 0;
 }
 
-static void device_event(DEVICE *device, char* event)
+static void device_event(DEVICE *device, const char* event)
 {
   BUFFER buffer;
   sprintf(buffer.body, "EVENT %s %s\r\n",
diff --git a/site_ansto/hardsup/Monitor/display.c b/site_ansto/hardsup/Monitor/display.c
index 98cee84d..2e127487 100644
--- a/site_ansto/hardsup/Monitor/display.c
+++ b/site_ansto/hardsup/Monitor/display.c
@@ -19,7 +19,7 @@
  * The browser will return name=value for the selection, using the name from
  * the selection box and the value from the option selected.
  */
-static void add_select_begin(BUFFER* buffer, char* title, char* name)
+static void add_select_begin(BUFFER* buffer, const char* title, const char* name)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -41,7 +41,7 @@ static void add_select_begin(BUFFER* buffer, char* title, char* name)
  * The browser will return name=value for the selection, using the name from
  * the selection box and the value from the option selected.
  */
-static void add_option(BUFFER* buffer, char* name, char* value, bool selected)
+static void add_option(BUFFER* buffer, const char* name, const char* value, bool selected)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -69,7 +69,7 @@ static void add_select_end(BUFFER* buffer)
  *
  * \param buffer where the text is appended
  */
-static void add_text(BUFFER* buffer, char* text)
+static void add_text(BUFFER* buffer, const char* text)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length, "%s", text);
@@ -87,7 +87,7 @@ static void add_text(BUFFER* buffer, char* text)
  * The title is displayed in column one and the integer in column two. The
  * name=value is returned by the browser.
  */
-static void add_int(BUFFER* buffer, char* title, char* name, int value)
+static void add_int(BUFFER* buffer, const char* title, const char* name, int value)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -111,7 +111,7 @@ static void add_int(BUFFER* buffer, char* title, char* name, int value)
  * The title is displayed in column one and the double in column two. The
  * name=value is returned by the browser.
  */
-static void add_double(BUFFER* buffer, char* title, char* name, double value)
+static void add_double(BUFFER* buffer, const char* title, const char* name, double value)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -135,7 +135,7 @@ static void add_double(BUFFER* buffer, char* title, char* name, double value)
  * The title is displayed in column one and the counter value in column two.
  * The name=value is returned by the browser.
  */
-static void add_counter(BUFFER* buffer, char* title, char* name, uint64 value)
+static void add_counter(BUFFER* buffer, const char* title, const char* name, uint64 value)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -266,7 +266,7 @@ static void show_text(BUFFER* buffer, const char* title, const char* value)
   buffer->length += strlen(bp);
 }
 
-static void show_int(BUFFER* buffer, char* title, int value)
+static void show_int(BUFFER* buffer, const char* title, int value)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -278,7 +278,7 @@ static void show_int(BUFFER* buffer, char* title, int value)
   buffer->length += strlen(bp);
 }
 
-static void show_real(BUFFER* buffer, char* title, double value)
+static void show_real(BUFFER* buffer, const char* title, double value)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -290,7 +290,7 @@ static void show_real(BUFFER* buffer, char* title, double value)
   buffer->length += strlen(bp);
 }
 
-static void show_counter(BUFFER* buffer, char* title, unsigned long long value)
+static void show_counter(BUFFER* buffer, const char* title, unsigned long long value)
 {
   char* bp = &buffer->body[buffer->length];
   snprintf(bp, sizeof(buffer->body) - buffer->length,
@@ -303,7 +303,7 @@ static void show_counter(BUFFER* buffer, char* title, unsigned long long value)
 }
 
 static void show_time(BUFFER* buffer,
-    char* title,
+    const char* title,
     struct timeval* value,
     bool days_flag)
 {
@@ -391,7 +391,7 @@ void put_page(int n)
   show_real(&buffer, "Max", sp->maximum_rate);
   if (pp->range_check_enable)
   {
-    char* result;
+    const char* result;
     if (device->range_error == 1)
       result = "<font color=\"BLUE\">LOW</font>";
     else if (device->range_error == 2)
diff --git a/site_ansto/hardsup/Monitor/params.c b/site_ansto/hardsup/Monitor/params.c
index a81a89f0..98cb2603 100644
--- a/site_ansto/hardsup/Monitor/params.c
+++ b/site_ansto/hardsup/Monitor/params.c
@@ -38,8 +38,8 @@
 #define TXT_FILTER      "FILTER"
 
 static struct param_command_t {
-  int cmd;
-  char* txt;
+  const int cmd;
+  const char* txt;
 } param_command[] = {
   {CMD_DIRECTION, TXT_DIRECTION},
   {CMD_SCAN, TXT_SCAN},
@@ -278,7 +278,7 @@ bool param_set_cmd(pPARAMETERS pp, char* cmd)
   return param_set(pp, name, value);
 }
 
-bool param_get_cmd(pPARAMETERS pp, char* cmd, int n)
+bool param_get_cmd(pPARAMETERS pp, const char* cmd, int n)
 {
   char name[100];
   int len;