diff --git a/tasmota/xdrv_15_pca9685.ino b/tasmota/xdrv_15_pca9685.ino
index 950a7df2b..254103d0a 100644
--- a/tasmota/xdrv_15_pca9685.ino
+++ b/tasmota/xdrv_15_pca9685.ino
@@ -119,20 +119,20 @@ bool PCA9685_Command(void)
     serviced = false;
     return serviced;
   }
-  char sub_string[XdrvMailbox.data_len];
+  char argument[XdrvMailbox.data_len];
   for (uint32_t ca=0;ca<XdrvMailbox.data_len;ca++) {
     if ((' ' == XdrvMailbox.data[ca]) || ('=' == XdrvMailbox.data[ca])) { XdrvMailbox.data[ca] = ','; }
     if (',' == XdrvMailbox.data[ca]) { paramcount++; }
   }
   UpperCase(XdrvMailbox.data,XdrvMailbox.data);
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET"))  {  PCA9685_Reset(); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET"))  {  PCA9685_Reset(); return serviced; }
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"STATUS"))  { PCA9685_OutputTelemetry(false); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"STATUS"))  { PCA9685_OutputTelemetry(false); return serviced; }
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"PWMF")) {
+  if (!strcmp(ArgV(argument, 1),"PWMF")) {
     if (paramcount > 1) {
-      uint16_t new_freq = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint16_t new_freq = atoi(ArgV(argument, 2));
       if ((new_freq >= 24) && (new_freq <= 1526)) {
         PCA9685_SetPWMfreq(new_freq);
         Response_P(PSTR("{\"PCA9685\":{\"PWMF\":%i, \"Result\":\"OK\"}}"),new_freq);
@@ -143,23 +143,23 @@ bool PCA9685_Command(void)
       return serviced;
     }
   }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"PWM")) {
+  if (!strcmp(ArgV(argument, 1),"PWM")) {
     if (paramcount > 1) {
-      uint8_t pin = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint8_t pin = atoi(ArgV(argument, 2));
       if (paramcount > 2) {
-        if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 3), "ON")) {
+        if (!strcmp(ArgV(argument, 3), "ON")) {
           PCA9685_SetPWM(pin, 4096, false);
           Response_P(PSTR("{\"PCA9685\":{\"PIN\":%i,\"PWM\":%i}}"),pin,4096);
           serviced = true;
           return serviced;
         }
-        if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 3), "OFF")) {
+        if (!strcmp(ArgV(argument, 3), "OFF")) {
           PCA9685_SetPWM(pin, 0, false);
           Response_P(PSTR("{\"PCA9685\":{\"PIN\":%i,\"PWM\":%i}}"),pin,0);
           serviced = true;
           return serviced;
         }
-        uint16_t pwm = atoi(subStr(sub_string, XdrvMailbox.data, ",", 3));
+        uint16_t pwm = atoi(ArgV(argument, 3));
         if ((pin >= 0 && pin <= 15) && (pwm >= 0 && pwm <= 4096)) {
           PCA9685_SetPWM(pin, pwm, false);
           Response_P(PSTR("{\"PCA9685\":{\"PIN\":%i,\"PWM\":%i}}"),pin,pwm);
diff --git a/tasmota/xsns_29_mcp230xx.ino b/tasmota/xsns_29_mcp230xx.ino
index d973f1b77..b450d63d7 100644
--- a/tasmota/xsns_29_mcp230xx.ino
+++ b/tasmota/xsns_29_mcp230xx.ino
@@ -451,25 +451,25 @@ bool MCP230xx_Command(void)
     serviced = false;
     return serviced;
   }
-  char sub_string[XdrvMailbox.data_len];
+  char argument[XdrvMailbox.data_len];
   for (uint32_t ca=0;ca<XdrvMailbox.data_len;ca++) {
     if ((' ' == XdrvMailbox.data[ca]) || ('=' == XdrvMailbox.data[ca])) { XdrvMailbox.data[ca] = ','; }
     if (',' == XdrvMailbox.data[ca]) { paramcount++; }
   }
   UpperCase(XdrvMailbox.data,XdrvMailbox.data);
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET"))  {  MCP230xx_Reset(1); return serviced; }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET1")) {  MCP230xx_Reset(1); return serviced; }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET2")) {  MCP230xx_Reset(2); return serviced; }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET3")) {  MCP230xx_Reset(3); return serviced; }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET4")) {  MCP230xx_Reset(4); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET"))  {  MCP230xx_Reset(1); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET1")) {  MCP230xx_Reset(1); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET2")) {  MCP230xx_Reset(2); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET3")) {  MCP230xx_Reset(3); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET4")) {  MCP230xx_Reset(4); return serviced; }
 #ifdef USE_MCP230xx_OUTPUT
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET5")) {  MCP230xx_Reset(5); return serviced; }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"RESET6")) {  MCP230xx_Reset(6); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET5")) {  MCP230xx_Reset(5); return serviced; }
+  if (!strcmp(ArgV(argument, 1),"RESET6")) {  MCP230xx_Reset(6); return serviced; }
 #endif // USE_MCP230xx_OUTPUT
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"INTPRI")) {
+  if (!strcmp(ArgV(argument, 1),"INTPRI")) {
     if (paramcount > 1) {
-      uint8_t intpri = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint8_t intpri = atoi(ArgV(argument, 2));
       if ((intpri >= 0) && (intpri <= 20)) {
         Settings.mcp230xx_int_prio = intpri;
         Response_P(MCP230XX_INTCFG_RESPONSE,"PRI",99,Settings.mcp230xx_int_prio);  // "{\"MCP230xx_INT%s\":{\"D_%i\":%i}}";
@@ -481,9 +481,9 @@ bool MCP230xx_Command(void)
     }
   }
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"INTTIMER")) {
+  if (!strcmp(ArgV(argument, 1),"INTTIMER")) {
     if (paramcount > 1) {
-      uint8_t inttim = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint8_t inttim = atoi(ArgV(argument, 2));
       if ((inttim >= 0) && (inttim <= 3600)) {
         Settings.mcp230xx_int_timer = inttim;
         MCP230xx_CheckForIntCounter(); // update register on whether or not we should be counting interrupts
@@ -496,19 +496,19 @@ bool MCP230xx_Command(void)
     }
   }
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"INTDEF")) {
+  if (!strcmp(ArgV(argument, 1),"INTDEF")) {
     if (paramcount > 1) {
-      uint8_t pin = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint8_t pin = atoi(ArgV(argument, 2));
       if (pin < mcp230xx_pincount) {
         if (pin == 0) {
-          if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "0")) validpin=true;
+          if (!strcmp(ArgV(argument, 2), "0")) validpin=true;
         } else {
           validpin = true;
         }
       }
       if (validpin) {
         if (paramcount > 2) {
-          uint8_t intdef = atoi(subStr(sub_string, XdrvMailbox.data, ",", 3));
+          uint8_t intdef = atoi(ArgV(argument, 3));
           if ((intdef >= 0) && (intdef <= 15)) {
             Settings.mcp230xx_config[pin].int_report_defer=intdef;
             if (Settings.mcp230xx_config[pin].int_count_en) {
@@ -535,19 +535,19 @@ bool MCP230xx_Command(void)
     }
   }
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"INTCNT")) {
+  if (!strcmp(ArgV(argument, 1),"INTCNT")) {
     if (paramcount > 1) {
-      uint8_t pin = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint8_t pin = atoi(ArgV(argument, 2));
       if (pin < mcp230xx_pincount) {
         if (pin == 0) {
-          if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "0")) validpin=true;
+          if (!strcmp(ArgV(argument, 2), "0")) validpin=true;
         } else {
           validpin = true;
         }
       }
       if (validpin) {
         if (paramcount > 2) {
-          uint8_t intcnt = atoi(subStr(sub_string, XdrvMailbox.data, ",", 3));
+          uint8_t intcnt = atoi(ArgV(argument, 3));
           if ((intcnt >= 0) && (intcnt <= 1)) {
             Settings.mcp230xx_config[pin].int_count_en=intcnt;
             if (Settings.mcp230xx_config[pin].int_report_defer) {
@@ -581,19 +581,19 @@ bool MCP230xx_Command(void)
     }
   }
 
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"INTRETAIN")) {
+  if (!strcmp(ArgV(argument, 1),"INTRETAIN")) {
     if (paramcount > 1) {
-      uint8_t pin = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      uint8_t pin = atoi(ArgV(argument, 2));
       if (pin < mcp230xx_pincount) {
         if (pin == 0) {
-          if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "0")) validpin=true;
+          if (!strcmp(ArgV(argument, 2), "0")) validpin=true;
         } else {
           validpin = true;
         }
       }
       if (validpin) {
         if (paramcount > 2) {
-          uint8_t int_retain = atoi(subStr(sub_string, XdrvMailbox.data, ",", 3));
+          uint8_t int_retain = atoi(ArgV(argument, 3));
           if ((int_retain >= 0) && (int_retain <= 1)) {
             Settings.mcp230xx_config[pin].int_retain_flag=int_retain;
             Response_P(MCP230XX_INTCFG_RESPONSE,"INT_RETAIN",pin,Settings.mcp230xx_config[pin].int_retain_flag);
@@ -616,17 +616,17 @@ bool MCP230xx_Command(void)
     }
   }
 
-  uint8_t pin = atoi(subStr(sub_string, XdrvMailbox.data, ",", 1));
+  uint8_t pin = atoi(ArgV(argument, 1));
 
   if (pin < mcp230xx_pincount) {
     if (0 == pin) {
-      if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1), "0")) validpin=true;
+      if (!strcmp(ArgV(argument, 1), "0")) validpin=true;
     } else {
       validpin=true;
     }
   }
   if (validpin && (paramcount > 1)) {
-    if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "?")) {
+    if (!strcmp(ArgV(argument, 2), "?")) {
       uint8_t port = 0;
       if (pin > 7) { port = 1; }
       uint8_t portdata = MCP230xx_readGPIO(port);
@@ -652,15 +652,15 @@ bool MCP230xx_Command(void)
         if ( mcp230xx_outpinmapping[relay_no] == pin) break;
       }
       relay_no = TasmotaGlobal.devices_present - mcp230xx_oldoutpincount + relay_no +1;
-      if ((!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "ON")) || (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "1"))) {
+      if ((!strcmp(ArgV(argument, 2), "ON")) || (!strcmp(ArgV(argument, 2), "1"))) {
         ExecuteCommandPower(relay_no, 1, SRC_IGNORE);
         return serviced;
       }
-      if ((!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "OFF")) || (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "0"))) {
+      if ((!strcmp(ArgV(argument, 2), "OFF")) || (!strcmp(ArgV(argument, 2), "0"))) {
         ExecuteCommandPower(relay_no, 0, SRC_IGNORE);
         return serviced;
       }
-      if ((!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "T")) || (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 2), "2")))  {
+      if ((!strcmp(ArgV(argument, 2), "T")) || (!strcmp(ArgV(argument, 2), "2")))  {
         ExecuteCommandPower(relay_no, 2, SRC_IGNORE);
         return serviced;
       }
@@ -670,13 +670,13 @@ bool MCP230xx_Command(void)
     uint8_t pullup = 0;
     uint8_t intmode = 0;
     if (paramcount > 1) {
-      pinmode = atoi(subStr(sub_string, XdrvMailbox.data, ",", 2));
+      pinmode = atoi(ArgV(argument, 2));
     }
     if (paramcount > 2) {
-      pullup = atoi(subStr(sub_string, XdrvMailbox.data, ",", 3));
+      pullup = atoi(ArgV(argument, 3));
     }
     if (paramcount > 3) {
-      intmode = atoi(subStr(sub_string, XdrvMailbox.data, ",", 4));
+      intmode = atoi(ArgV(argument, 4));
     }
 #ifdef USE_MCP230xx_OUTPUT
     if ((pin < mcp230xx_pincount) && (pinmode > 0) && (pinmode < 7) && (pullup < 2) && (paramcount > 2)) {
diff --git a/tasmota/xsns_34_hx711.ino b/tasmota/xsns_34_hx711.ino
index aeb54f542..db89f432e 100644
--- a/tasmota/xsns_34_hx711.ino
+++ b/tasmota/xsns_34_hx711.ino
@@ -193,7 +193,7 @@ bool HxCommand(void)
 {
   bool serviced = true;
   bool show_parms = false;
-  char sub_string[XdrvMailbox.data_len +1];
+  char argument[XdrvMailbox.data_len];
 
   for (uint32_t ca = 0; ca < XdrvMailbox.data_len; ca++) {
     if ((' ' == XdrvMailbox.data[ca]) || ('=' == XdrvMailbox.data[ca])) { XdrvMailbox.data[ca] = ','; }
@@ -206,7 +206,7 @@ bool HxCommand(void)
       break;
     case 2:  // Calibrate
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-        Settings.weight_reference = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10);
+        Settings.weight_reference = strtol(ArgV(argument, 2), nullptr, 10);
       }
       Hx.scale = 1;
       HxReset();
@@ -216,26 +216,26 @@ bool HxCommand(void)
       break;
     case 3:  // WeightRef to user reference
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-        Settings.weight_reference = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10);
+        Settings.weight_reference = strtol(ArgV(argument, 2), nullptr, 10);
       }
       show_parms = true;
       break;
     case 4:  // WeightCal to user calculated value
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-        Settings.weight_calibration = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10);
+        Settings.weight_calibration = strtol(ArgV(argument, 2), nullptr, 10);
         Hx.scale = Settings.weight_calibration;
       }
       show_parms = true;
       break;
     case 5:  // WeightMax
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-        Settings.weight_max = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10) / 1000;
+        Settings.weight_max = strtol(ArgV(argument, 2), nullptr, 10) / 1000;
       }
       show_parms = true;
       break;
     case 6:  // WeightItem
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-        Settings.weight_item = (unsigned long)(CharToFloat(subStr(sub_string, XdrvMailbox.data, ",", 2)) * 10);
+        Settings.weight_item = (unsigned long)(CharToFloat(ArgV(argument, 2)) * 10);
       }
       show_parms = true;
       break;
@@ -245,13 +245,13 @@ bool HxCommand(void)
       break;
     case 8:  // Json on weight change
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-        Settings.SensorBits1.hx711_json_weight_change = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10) & 1;
+        Settings.SensorBits1.hx711_json_weight_change = strtol(ArgV(argument, 2), nullptr, 10) & 1;
       }
       show_parms = true;
       break;
     case 9:  // WeightDelta
       if (strchr(XdrvMailbox.data, ',') != nullptr) {
-	Settings.weight_change = strtol(subStr(sub_string, XdrvMailbox.data, ",", 2), nullptr, 10);
+	Settings.weight_change = strtol(ArgV(argument, 2), nullptr, 10);
 	SetWeightDelta();
       }
       show_parms = true;
diff --git a/tasmota/xsns_40_pn532.ino b/tasmota/xsns_40_pn532.ino
index 4f03f185d..03eba20c7 100644
--- a/tasmota/xsns_40_pn532.ino
+++ b/tasmota/xsns_40_pn532.ino
@@ -500,29 +500,28 @@ bool PN532_Command(void) {
     serviced = false;
     return serviced;
   }
-  char sub_string[XdrvMailbox.data_len];
-  char sub_string_tmp[XdrvMailbox.data_len];
+  char argument[XdrvMailbox.data_len];
   for (uint32_t ca=0;ca<XdrvMailbox.data_len;ca++) {
     if ((' ' == XdrvMailbox.data[ca]) || ('=' == XdrvMailbox.data[ca])) { XdrvMailbox.data[ca] = ','; }
     if (',' == XdrvMailbox.data[ca]) { paramcount++; }
   }
   UpperCase(XdrvMailbox.data,XdrvMailbox.data);
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"E")) {
+  if (!strcmp(ArgV(argument, 1),"E")) {
     Pn532.function = 1; // Block 1 of next card/tag will be reset to 0x00...
     AddLog(LOG_LEVEL_INFO, PSTR("NFC: PN532 NFC - Next scanned tag data block 1 will be erased"));
     ResponseTime_P(PSTR(",\"PN532\":{\"COMMAND\":\"E\"}}"));
     return serviced;
   }
-  if (!strcmp(subStr(sub_string, XdrvMailbox.data, ",", 1),"S")) {
+  if (!strcmp(ArgV(argument, 1),"S")) {
     if (paramcount > 1) {
       if (XdrvMailbox.data[XdrvMailbox.data_len-1] == ',') {
         serviced = false;
         return serviced;
       }
-      sprintf(sub_string_tmp,subStr(sub_string, XdrvMailbox.data, ",", 2));
-      Pn532.newdata_len = strlen(sub_string_tmp);
+      ArgV(argument, 2);
+      Pn532.newdata_len = strlen(argument);
       if (Pn532.newdata_len > 15) { Pn532.newdata_len = 15; }
-      memcpy(&Pn532.newdata,&sub_string_tmp,Pn532.newdata_len);
+      memcpy(&Pn532.newdata,&argument,Pn532.newdata_len);
       Pn532.newdata[Pn532.newdata_len] = 0x00; // Null terminate the string
       Pn532.function = 2;
       AddLog(LOG_LEVEL_INFO, PSTR("NFC: PN532 NFC - Next scanned tag data block 1 will be set to '%s'"), Pn532.newdata);