diff --git a/main/driver.c b/main/driver.c
index 01f0b4e..faabfc1 100644
--- a/main/driver.c
+++ b/main/driver.c
@@ -477,10 +477,13 @@ IRAM_ATTR static void driver_delay_ms (uint32_t ms, void (*callback)(void))
             xTimerDelete(xDelayTimer, 3);
             xDelayTimer = NULL;
         }
-        xDelayTimer = xTimerCreate("msDelay", pdMS_TO_TICKS(ms), pdFALSE, callback, vTimerCallback);
-        xTimerStartFromISR(xDelayTimer, &xHigherPriorityTaskWoken);
-        if(xHigherPriorityTaskWoken)
-            portYIELD_FROM_ISR();
+        if(ms) {
+            xDelayTimer = xTimerCreate("msDelay", pdMS_TO_TICKS(ms), pdFALSE, callback, vTimerCallback);
+            xTimerStartFromISR(xDelayTimer, &xHigherPriorityTaskWoken);
+            if(xHigherPriorityTaskWoken)
+                portYIELD_FROM_ISR();
+        } else
+            callback();
     } else {
         if(xDelayTimer) {
             xTimerDelete(xDelayTimer, 3);
@@ -2735,7 +2738,7 @@ bool driver_init (void)
 #else
     hal.info = "ESP32";
 #endif
-    hal.driver_version = "240127";
+    hal.driver_version = "240202";
     hal.driver_url = GRBL_URL "/ESP32";
 #ifdef BOARD_NAME
     hal.board = BOARD_NAME;
diff --git a/main/ioports.c b/main/ioports.c
index 8c332a9..64dc8f5 100644
--- a/main/ioports.c
+++ b/main/ioports.c
@@ -326,8 +326,7 @@ static void on_setting_changed (setting_id_t id)
     switch(id) {
 
         case Settings_IoPort_InvertIn:
-            port = digital.in.n_ports;
-            do {
+            if((port = digital.in.n_ports)) do {
                 port--;
                 aux_in[port].mode.inverted = !!(settings.ioport.invert_in.mask & (1 << port));
                 if(aux_in[port].aux_ctrl) {
@@ -341,8 +340,7 @@ static void on_setting_changed (setting_id_t id)
             break;
 
         case Settings_IoPort_InvertOut:
-            if(invert_digital_out.mask != settings.ioport.invert_out.mask) {
-                port = digital.out.n_ports;
+            if((port = digital.out.n_ports) && invert_digital_out.mask != settings.ioport.invert_out.mask) {
                 do {
                     port--;
                     aux_out[port].mode.inverted = !!(settings.ioport.invert_out.mask & (1 << port));
@@ -355,8 +353,7 @@ static void on_setting_changed (setting_id_t id)
             break;
 
         case Setting_ControlInvertMask:
-            port = digital.in.n_ports;
-            do {
+            if((port = digital.in.n_ports)) do {
                 if(aux_in[--port].aux_ctrl) {
                     write = true;
                     if(settings.control_invert.mask & aux_in[port].aux_ctrl->cap.mask)
@@ -379,18 +376,17 @@ static void on_setting_changed (setting_id_t id)
 static void on_settings_loaded (void)
 {
     bool write = false;
-    uint_fast8_t port = digital.out.n_ports;
+    uint_fast8_t port;
 
     invert_digital_out = settings.ioport.invert_out;
 
-    if(digital.out.n_ports) do {
+    if((port = digital.out.n_ports)) do {
         port--;
         aux_out[port].mode.inverted = !!(settings.ioport.invert_out.mask & (1 << port));
         DIGITAL_OUT(aux_out[port].pin, aux_out[port].mode.inverted);
     } while(port);
 
-    port = digital.in.n_ports;
-    do {
+    if((port = digital.in.n_ports)) do {
         if(aux_in[--port].aux_ctrl &&
             !!(settings.control_invert.mask & aux_in[port].aux_ctrl->cap.mask) !=
              !!(settings.ioport.invert_in.mask & (1 << port))) {