diff --git a/Arduino/CanGrow/include/CanGrow.h b/Arduino/CanGrow/include/CanGrow.h
index 9eb890b..9933a4e 100644
--- a/Arduino/CanGrow/include/CanGrow.h
+++ b/Arduino/CanGrow/include/CanGrow.h
@@ -63,6 +63,8 @@
  *   5 - NO_PWM: No PWM output
  *   6 - PWM_BOOT: PWM at boot time
  */
+const byte GPIO_Index_len = 6;
+
 const byte BOOTFAILS_LOW = 1;
 const byte BOOTFAILS_HIGH = 2;
 const byte FLASHMODE_LOW = 3;
@@ -70,6 +72,25 @@ const byte INPUT_ONLY = 4;
 const byte NO_PWM = 5;
 const byte HIGH_BOOT = 6;
 
+
+char BOOTFAILS_LOW_descr[] = "BF_LOW";
+char BOOTFAILS_HIGH_descr[] = "BF_HIGH";
+char FLASMODE_LOW_descr[] = "FM_LOW";
+char INPUT_ONLY_descr[] = "IN_ONLY";
+char NO_PWM_descr[] = "NO_PWM";
+char HIGH_BOOT_descr[] = "B_HIGH";
+
+const char * GPIO_Index_note[] = {
+  NULL, // 0 - no note
+  BOOTFAILS_LOW_descr, // 1
+  BOOTFAILS_HIGH_descr, // 2
+  FLASMODE_LOW_descr, // 3
+  INPUT_ONLY_descr, // 4
+  NO_PWM_descr, // 5
+  HIGH_BOOT_descr, // 6
+};
+
+
 const byte OUTPUT_TYPE_GPIO = 1;
 const byte OUTPUT_TYPE_I2C = 2;
 const byte OUTPUT_TYPE_WEB = 3;
diff --git a/Arduino/CanGrow/include/Webserver/Page_system.h b/Arduino/CanGrow/include/Webserver/Page_system.h
index 4514fa4..8c5eb98 100644
--- a/Arduino/CanGrow/include/Webserver/Page_system.h
+++ b/Arduino/CanGrow/include/Webserver/Page_system.h
@@ -369,37 +369,30 @@ String Proc_WebPage_system_output_add(const String& var) {
     
   } else if(var == "GPIO_INDEX") {
     String gpioIndex_html;
+    // iterate through through all available GPIOs in index
     for(byte i = 0; i < GPIOindex_length; i++) {
       gpioIndex_html += "<option value='";
       gpioIndex_html += i;
       gpioIndex_html += "'";
-      // set disabled option of gpio is already in use
-      if(Check_GPIOindex_Used(i) == true) {
+      // set disabled option for gpio which are already in use or incompatible
+      if((Check_GPIOindex_Used(i) == true) || (GPIOindex[i].note == INPUT_ONLY)) {
         gpioIndex_html += " disabled";
       }
-      
       gpioIndex_html += ">GPIO ";
       gpioIndex_html += GPIOindex[i].gpio;
       //add gpio note if there is some
-      if(GPIOindex[i].note > 0) {
-        switch(GPIOindex[i].note) {
-          case BOOTFAILS_LOW: gpioIndex_html += " BFL"; break;
-          case BOOTFAILS_HIGH: gpioIndex_html += " BFH"; break;
-          case FLASHMODE_LOW: gpioIndex_html += " FML"; break;
-          case INPUT_ONLY: gpioIndex_html += " INO"; break;
-          case NO_PWM: gpioIndex_html += " NPWM"; break;
-          case HIGH_BOOT: gpioIndex_html += " HB"; break;
-          default: break;
-        }
-      }
-      // add USED if gpio is already in use
-      if(Check_GPIOindex_Used(i) == true) {
-        gpioIndex_html += " USED";
+      //if(GPIOindex[i].note > 0) {
+      gpioIndex_html += " ";
+      gpioIndex_html += GPIO_Index_note[GPIOindex[i].note];
+
+      // disable output incompatible gpio
+      if(GPIOindex[i].note == INPUT_ONLY) {
+        gpioIndex_html += " (N/A)";
+      // add USED if gpio is already in use  
+      } else if(Check_GPIOindex_Used(i) == true) {
+        gpioIndex_html += " (used)";
       }
       gpioIndex_html += "</option>";
-
-      
-      
     }
     return gpioIndex_html;
   } else {