diff --git a/sonoff/_changelog.ino b/sonoff/_changelog.ino
index 36de9f29c..c54e2199d 100644
--- a/sonoff/_changelog.ino
+++ b/sonoff/_changelog.ino
@@ -3,6 +3,7 @@
  * Update TasmotaModbus and TasmotaSerial libraries for support of serial 8N2 communication
  * Add support for Pzem-003/017 DC Energy monitoring module (#3694)
  * Change support for Pzem-014/016 AC Energy monitoring module (#3694)
+ * Rewrite Tuya Dimmer code
  *
  * 6.2.1.16 20181015
  * Add TasmotaModbus library for very basic modbus wrapper for TasmotaSerial
diff --git a/sonoff/sonoff.h b/sonoff/sonoff.h
index eb99cc2a1..8acbc8db5 100644
--- a/sonoff/sonoff.h
+++ b/sonoff/sonoff.h
@@ -202,7 +202,7 @@ enum ButtonStates { PRESSED, NOT_PRESSED };
 
 enum Shortcuts { SC_CLEAR, SC_DEFAULT, SC_USER };
 
-enum SettingsParmaIndex {P_HOLD_TIME, P_MAX_POWER_RETRY, P_MAX_PARAM8};
+enum SettingsParmaIndex {P_HOLD_TIME, P_MAX_POWER_RETRY, P_TUYA_DIMMER_ID, P_MAX_PARAM8};
 
 enum DomoticzSensors {DZ_TEMP, DZ_TEMP_HUM, DZ_TEMP_HUM_BARO, DZ_POWER_ENERGY, DZ_ILLUMINANCE, DZ_COUNT, DZ_VOLTAGE, DZ_CURRENT, DZ_AIRQUALITY, DZ_MAX_SENSORS};
 
@@ -212,7 +212,7 @@ enum LightTypes {LT_BASIC, LT_PWM1, LT_PWM2, LT_PWM3, LT_PWM4, LT_PWM5, LT_PWM6,
 enum LichtSubtypes {LST_NONE, LST_SINGLE, LST_COLDWARM, LST_RGB, LST_RGBW, LST_RGBWC};
 enum LichtSchemes {LS_POWER, LS_WAKEUP, LS_CYCLEUP, LS_CYCLEDN, LS_RANDOM, LS_MAX};
 
-enum XsnsFunctions {FUNC_PRE_INIT, FUNC_INIT, FUNC_LOOP, FUNC_EVERY_50_MSECOND, FUNC_EVERY_100_MSECOND, FUNC_EVERY_200_MSECOND, FUNC_EVERY_250_MSECOND, FUNC_EVERY_SECOND, FUNC_PREP_BEFORE_TELEPERIOD,
+enum XsnsFunctions {FUNC_MODULE_INIT, FUNC_PRE_INIT, FUNC_INIT, FUNC_LOOP, FUNC_EVERY_50_MSECOND, FUNC_EVERY_100_MSECOND, FUNC_EVERY_200_MSECOND, FUNC_EVERY_250_MSECOND, FUNC_EVERY_SECOND, FUNC_PREP_BEFORE_TELEPERIOD,
                     FUNC_JSON_APPEND, FUNC_WEB_APPEND, FUNC_SAVE_BEFORE_RESTART, FUNC_COMMAND, FUNC_MQTT_SUBSCRIBE, FUNC_MQTT_INIT, FUNC_MQTT_DATA, FUNC_SET_POWER, FUNC_SHOW_SENSOR,
                     FUNC_RULES_PROCESS, FUNC_SERIAL, FUNC_FREE_MEM, FUNC_WEB_ADD_BUTTON, FUNC_WEB_ADD_MAIN_BUTTON, FUNC_WEB_ADD_HANDLER};
 
diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index a5dbcef4e..edb9253fb 100755
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -200,8 +200,6 @@ char mqtt_data[MESSZ];                      // MQTT publish buffer and web page
 char log_data[LOGSZ];                       // Logging
 char web_log[WEB_LOG_SIZE] = {'\0'};        // Web log buffer
 String backlog[MAX_BACKLOG];                // Command backlog
-uint8_t tuya_new_dim = 0;                   // Tuya dimmer value temp
-boolean tuya_ignore_dim = false;            // Flag to skip serial send to prevent looping when processing inbound states from the faceplate interaction
 
 /********************************************************************************************/
 
@@ -342,9 +340,11 @@ void SetDevicePower(power_t rpower, int source)
   }
 
   XdrvMailbox.index = rpower;
-  XdrvCall(FUNC_SET_POWER);
+  XdrvMailbox.payload = source;
+  if (XdrvCall(FUNC_SET_POWER)) {
 
-  if ((SONOFF_DUAL == Settings.module) || (CH4 == Settings.module)) {
+  }
+  else if ((SONOFF_DUAL == Settings.module) || (CH4 == Settings.module)) {
     Serial.write(0xA0);
     Serial.write(0x04);
     Serial.write(rpower &0xFF);
@@ -352,23 +352,6 @@ void SetDevicePower(power_t rpower, int source)
     Serial.write('\n');
     Serial.flush();
   }
-  else if (TUYA_DIMMER == Settings.module && source != SRC_SWITCH ) {  // ignore to prevent loop from pushing state from faceplate interaction
-    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: SetDevicePower.rpower=%d"), rpower);
-    AddLog(LOG_LEVEL_DEBUG);
-    Serial.write(0x55); // Tuya header 55AA
-    Serial.write(0xAA);
-    Serial.write(0x00); // version 00
-    Serial.write(0x06); // Tuya command 06
-    Serial.write(0x00);
-    Serial.write(0x05); // following data length 0x05
-    Serial.write(0x01); // relay number 1,2,3
-    Serial.write(0x01);
-    Serial.write(0x00);
-    Serial.write(0x01);
-    Serial.write(rpower); // status
-    Serial.write(0x0D + rpower); // checksum sum of all bytes in packet mod 256
-    Serial.flush();
-  }
   else if (EXS_RELAY == Settings.module) {
     SetLatchingRelay(rpower, 1);
   }
@@ -770,19 +753,16 @@ void MqttDataHandler(char* topic, byte* data, unsigned int data_len)
           }
         }
         else {                   // SetOption32 .. 49
-/*
+          uint8_t param_low = 0;
+          uint8_t param_high = 255;
           switch (pindex) {
             case P_HOLD_TIME:
             case P_MAX_POWER_RETRY:
-              if ((payload >= 1) && (payload <= 250)) {
-                Settings.param[pindex] = payload;
-              }
+              param_low = 1;
+              param_high = 250;
               break;
-            default:
-              ptype = 99;        // Command Error
           }
-*/
-          if ((payload >= 1) && (payload <= 250)) {
+          if ((payload >= param_low) && (payload <= param_high)) {
             Settings.param[pindex] = payload;
           }
         }
@@ -2234,48 +2214,6 @@ void ArduinoOTAInit()
 
 /********************************************************************************************/
 
-void TuyaPacketProcess()
-{
-  char scmnd[20];
-  snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Packet Size=%d"), serial_in_byte_counter);
-  AddLog(LOG_LEVEL_DEBUG);
-  if (serial_in_byte_counter == 7 && serial_in_buffer[3] == 14 ) {  // heartbeat packet
-    AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: Heartbeat"));
-  }
-  if (serial_in_byte_counter == 12 && serial_in_buffer[3] == 7 && serial_in_buffer[5] == 5) {  // on/off packet
-    if (serial_in_buffer[10] == 0) {
-      AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: Rcvd - Off State"));
-      ExecuteCommandPower(1, 0, SRC_SWITCH);  // send SRC_SWITCH? to use as flag to prevent loop from inbound states from faceplate interaction
-    } else
-    {
-      AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: Rcvd - On State"));
-      ExecuteCommandPower(1, 1, SRC_SWITCH);  // send SRC_SWITCH? to use as flag to prevent loop from inbound states from faceplate interaction
-    }
-    serial_in_byte_counter = 0;
-    serial_in_buffer[serial_in_byte_counter] = 0;  // serial data completed
-  }
-  if (serial_in_byte_counter == 15 && serial_in_buffer[3] == 7 && serial_in_buffer[5] == 8) {  // dim packet
-    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Rcvd Dim State=%d"), serial_in_buffer[13]);
-    AddLog(LOG_LEVEL_DEBUG);
-    tuya_new_dim = round(serial_in_buffer[13] * (100. / 255.));
-    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Send CMND_DIMMER=%d"), tuya_new_dim );
-    AddLog(LOG_LEVEL_DEBUG);
-    snprintf_P(scmnd, sizeof(scmnd), PSTR(D_CMND_DIMMER " %d"), tuya_new_dim );
-    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Send CMND_DIMMER_STR=%s"), scmnd );
-    AddLog(LOG_LEVEL_DEBUG);
-    tuya_ignore_dim = true;
-    ExecuteCommand(scmnd, SRC_SWITCH);
-    serial_in_byte_counter = 0;
-    serial_in_buffer[serial_in_byte_counter] = 0;  // serial data completed
-  }
-  if (serial_in_byte_counter == 8 && serial_in_buffer[3] == 5 && serial_in_buffer[5] == 1 && serial_in_buffer[7] == 5 ) {  // reset WiFi settings packet - to do: reset red MCU LED after WiFi is up
-    AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: WiFi Reset Rcvd"));
-    serial_in_byte_counter = 0;
-    serial_in_buffer[serial_in_byte_counter] = 0;  // serial data completed
-    snprintf_P(scmnd, sizeof(scmnd), D_CMND_WIFICONFIG " 2");
-    ExecuteCommand(scmnd, SRC_BUTTON);
-  }
-}
 void SerialInput()
 {
   while (Serial.available()) {
@@ -2304,29 +2242,6 @@ void SerialInput()
       }
     }
 
-/*-------------------------------------------------------------------------------------------*\
- * Tuya based Dimmer with Serial Communications to MCU dimmer at 9600 baud
-\*-------------------------------------------------------------------------------------------*/
-    if (TUYA_DIMMER == Settings.module) {
-      if (serial_in_byte == '\x55') {            // Start TUYA Packet
-        if (serial_in_byte_counter > 0 && serial_in_byte_counter < 11) {
-           TuyaPacketProcess();
-        }
-        AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: 0x55 Packet Start"));
-        serial_in_byte_counter = 0;
-        serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
-//        return;  // test to see if we need this
-      } else {                                  // read additional packets from TUYA
-      if (serial_in_byte_counter < INPUT_BUFFER_SIZE -1) {  // add char to string if it still fits
-        serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
-        serial_polling_window = millis();
-//        return;  // test to see if we need this
-      } else {
-        serial_in_byte_counter = 0;
-      }
-     }
-    }
-
 /*-------------------------------------------------------------------------------------------*/
 
     if (XdrvCall(FUNC_SERIAL)) {
@@ -2336,33 +2251,33 @@ void SerialInput()
     }
 
 /*-------------------------------------------------------------------------------------------*/
-    if (TUYA_DIMMER != Settings.module) {
-      if (serial_in_byte > 127 && !Settings.flag.mqtt_serial_raw) { // binary data...
-        serial_in_byte_counter = 0;
-        Serial.flush();
-        return;
-      }
-      if (!Settings.flag.mqtt_serial) {
-        if (isprint(serial_in_byte)) {
-          if (serial_in_byte_counter < INPUT_BUFFER_SIZE -1) {  // add char to string if it still fits
-            serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
-          } else {
-            serial_in_byte_counter = 0;
-          }
+
+    if (serial_in_byte > 127 && !Settings.flag.mqtt_serial_raw) { // binary data...
+      serial_in_byte_counter = 0;
+      Serial.flush();
+      return;
+    }
+    if (!Settings.flag.mqtt_serial) {
+      if (isprint(serial_in_byte)) {
+        if (serial_in_byte_counter < INPUT_BUFFER_SIZE -1) {  // add char to string if it still fits
+          serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
+        } else {
+          serial_in_byte_counter = 0;
         }
-      } else {
-        if (serial_in_byte || Settings.flag.mqtt_serial_raw) {
-          if ((serial_in_byte_counter < INPUT_BUFFER_SIZE -1) &&
-              ((serial_in_byte != Settings.serial_delimiter) || Settings.flag.mqtt_serial_raw)) {  // add char to string if it still fits
-            serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
-            serial_polling_window = millis();
-          } else {
-            serial_polling_window = 0;
-            break;
-          }
+      }
+    } else {
+      if (serial_in_byte || Settings.flag.mqtt_serial_raw) {
+        if ((serial_in_byte_counter < INPUT_BUFFER_SIZE -1) &&
+            ((serial_in_byte != Settings.serial_delimiter) || Settings.flag.mqtt_serial_raw)) {  // add char to string if it still fits
+          serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
+          serial_polling_window = millis();
+        } else {
+          serial_polling_window = 0;
+          break;
         }
       }
     }
+
 /*-------------------------------------------------------------------------------------------*\
  * Sonoff SC 19200 baud serial interface
 \*-------------------------------------------------------------------------------------------*/
@@ -2391,32 +2306,20 @@ void SerialInput()
     }
   }
 
-  if (TUYA_DIMMER == Settings.module && serial_in_byte_counter > 6 && (millis() > (serial_polling_window + SERIAL_POLLING))) {
-    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: 0x55 Packet End: \""));
-    for (int i = 0; i < serial_in_byte_counter; i++) {
-      snprintf_P(log_data, sizeof(log_data), PSTR("%s%02x"), log_data, serial_in_buffer[i]);
-    }
-    snprintf_P(log_data, sizeof(log_data), PSTR("%s\""), log_data);
-    AddLog(LOG_LEVEL_DEBUG);
-    TuyaPacketProcess();
+  if (Settings.flag.mqtt_serial && serial_in_byte_counter && (millis() > (serial_polling_window + SERIAL_POLLING))) {
     serial_in_buffer[serial_in_byte_counter] = 0;  // serial data completed
-    serial_in_byte_counter = 0;
-  } else {
-    if (Settings.flag.mqtt_serial && serial_in_byte_counter && (millis() > (serial_polling_window + SERIAL_POLLING))) {
-      serial_in_buffer[serial_in_byte_counter] = 0;  // serial data completed
-      if (!Settings.flag.mqtt_serial_raw) {
-        snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("{\"" D_JSON_SERIALRECEIVED "\":\"%s\"}"), serial_in_buffer);
-      } else {
-        snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("{\"" D_JSON_SERIALRECEIVED "\":\""));
-        for (int i = 0; i < serial_in_byte_counter; i++) {
-          snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s%02x"), mqtt_data, serial_in_buffer[i]);
-        }
-        snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s\"}"), mqtt_data);
+    if (!Settings.flag.mqtt_serial_raw) {
+      snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("{\"" D_JSON_SERIALRECEIVED "\":\"%s\"}"), serial_in_buffer);
+    } else {
+      snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("{\"" D_JSON_SERIALRECEIVED "\":\""));
+      for (int i = 0; i < serial_in_byte_counter; i++) {
+        snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s%02x"), mqtt_data, serial_in_buffer[i]);
       }
-      MqttPublishPrefixTopic_P(RESULT_OR_TELE, PSTR(D_JSON_SERIALRECEIVED));
-//      XdrvRulesProcess();
-      serial_in_byte_counter = 0;
+      snprintf_P(mqtt_data, sizeof(mqtt_data), PSTR("%s\"}"), mqtt_data);
     }
+    MqttPublishPrefixTopic_P(RESULT_OR_TELE, PSTR(D_JSON_SERIALRECEIVED));
+//      XdrvRulesProcess();
+    serial_in_byte_counter = 0;
   }
 }
 /********************************************************************************************/
@@ -2545,7 +2448,9 @@ void GpioInit()
     baudrate = 19200;
   }
 
-  if (SONOFF_DUAL == Settings.module) {
+  if (XdrvCall(FUNC_MODULE_INIT)) {
+  }
+  else if (SONOFF_DUAL == Settings.module) {
     Settings.flag.mqtt_serial = 0;
     devices_present = 2;
     baudrate = 19200;
@@ -2560,11 +2465,6 @@ void GpioInit()
     devices_present = 0;
     baudrate = 19200;
   }
-  else if (TUYA_DIMMER == Settings.module) {
-    Settings.flag.mqtt_serial = 0;
-    baudrate = 9600;
-    light_type = LT_SERIAL;
-  }
   else if (SONOFF_BN == Settings.module) {   // PWM Single color led (White)
     light_type = LT_PWM1;
   }
diff --git a/sonoff/sonoff_template.h b/sonoff/sonoff_template.h
index b7d591801..ad2a44e6b 100644
--- a/sonoff/sonoff_template.h
+++ b/sonoff/sonoff_template.h
@@ -1138,13 +1138,19 @@ const mytmplt kModules[MAXMODULE] PROGMEM = {
   },
   { "Tuya Dimmer",     // Tuya Dimmer (ESP8266 w/ separate MCU dimmer)
                        // https://www.amazon.com/gp/product/B07CTNSZZ8/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
-     0,
-     GPIO_TXD,         // TX to dimmer MCU
-     0,
-     GPIO_RXD,         // RX from dimmer MCU
-     0, 0,
+     GPIO_KEY1,        // Virtual Button (controlled by MCU)
+     GPIO_TXD,         // GPIO01 MCU serial control
+     GPIO_USER,
+     GPIO_RXD,         // GPIO03 MCU serial control
+     GPIO_USER,
+     GPIO_USER,
      0, 0, 0, 0, 0, 0, // Flash connection
-     0, 0, 0, 0, 0, 0
+     GPIO_USER,
+     GPIO_USER,
+     GPIO_LED1,        // GPIO14 Green Led
+     GPIO_USER,
+     GPIO_USER,
+     0
   }
 };
 
diff --git a/sonoff/user_config.h b/sonoff/user_config.h
index 1d66a92c4..32fbaa8ca 100644
--- a/sonoff/user_config.h
+++ b/sonoff/user_config.h
@@ -378,6 +378,9 @@
 
 #define USE_RF_FLASH                             // Add support for flashing the EFM8BB1 chip on the Sonoff RF Bridge. C2CK must be connected to GPIO4, C2D to GPIO5 on the PCB (+3k code)
 
+#define USE_TUYA_DIMMER                          // Add support for Tuya Serial Dimmer
+  #define TUYA_DIMMER_ID       3                 // Default dimmer Id
+
 /*********************************************************************************************\
  * Debug features are only supported in development branch
 \*********************************************************************************************/
diff --git a/sonoff/xdrv_04_light.ino b/sonoff/xdrv_04_light.ino
index a4f58ae67..c5ba2acc7 100644
--- a/sonoff/xdrv_04_light.ino
+++ b/sonoff/xdrv_04_light.ino
@@ -343,37 +343,6 @@ void LightMy92x1Duty(uint8_t duty_r, uint8_t duty_g, uint8_t duty_b, uint8_t dut
   os_delay_us(12);                      // TStop > 12us.
 }
 
-// *************** Tuya Dimmer Serial Comms
-void LightSerialDuty(uint8_t duty)
-{
-  if (duty > 0 && !tuya_ignore_dim ) {
-    if (duty < 25) {
-      duty = 25;  // dimming acts odd below 25(10%) - this mirrors the threshold set on the faceplate itself
-    }
-    Serial.write(0x55); // Tuya header 55AA
-    Serial.write(0xAA);
-    Serial.write(0x00); // version 00
-    Serial.write(0x06); // Tuya command 06 - send order
-    Serial.write(0x00);
-    Serial.write(0x08); // following data length 0x08
-    Serial.write(0x03); // dimmer id
-    Serial.write(0x02); // type=value
-    Serial.write(0x00); // length hi
-    Serial.write(0x04); // length low
-    Serial.write(0x00); // 
-    Serial.write(0x00); // 
-    Serial.write(0x00); // 
-    Serial.write( duty ); // dim value (0-255)
-    Serial.write( byte(22 + duty) ); // checksum:sum of all bytes in packet mod 256
-    Serial.flush();
-    snprintf_P(log_data, sizeof(log_data), PSTR( "TYA: Send Serial Packet Dim Value=%d"), duty);
-    AddLog(LOG_LEVEL_DEBUG);
-  } else {
-    tuya_ignore_dim = false;  // reset flag
-    snprintf_P(log_data, sizeof(log_data), PSTR( "TYA: Send Dim Level skipped due to 0 or already set. Value=%d"), duty);
-    AddLog(LOG_LEVEL_DEBUG);
-  }
-}
 /********************************************************************************************/
 
 void LightInit()
@@ -424,7 +393,7 @@ void LightInit()
 #endif  // USE_WS2812 ************************************************************************
   else if (LT_SERIAL == light_type) {
     light_subtype = LST_SINGLE;
-  }  
+  }
   else {
     light_pdi_pin = pin[GPIO_DI];
     light_pdcki_pin = pin[GPIO_DCKI];
@@ -855,9 +824,11 @@ void LightAnimate()
       if (light_type > LT_WS2812) {
         LightMy92x1Duty(cur_col[0], cur_col[1], cur_col[2], cur_col[3], cur_col[4]);
       }
+#ifdef USE_TUYA_DIMMER
       if (light_type == LT_SERIAL) {
         LightSerialDuty(cur_col[0]);
       }
+#endif  // USE_TUYA_DIMMER
     }
   }
 }
diff --git a/sonoff/xdrv_16_tuyadimmer.ino b/sonoff/xdrv_16_tuyadimmer.ino
new file mode 100644
index 000000000..cb5c31038
--- /dev/null
+++ b/sonoff/xdrv_16_tuyadimmer.ino
@@ -0,0 +1,263 @@
+/*
+  xdrv_16_tuyadimmer.ino - Tuya dimmer support for Sonoff-Tasmota
+
+  Copyright (C) 2018  digiblur, Joel Stein and Theo Arends
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifdef USE_TUYA_DIMMER
+
+#ifndef TUYA_DIMMER_ID
+#define TUYA_DIMMER_ID  3
+#endif
+
+uint8_t tuya_new_dim = 0;                   // Tuya dimmer value temp
+boolean tuya_ignore_dim = false;            // Flag to skip serial send to prevent looping when processing inbound states from the faceplate interaction
+uint8_t tuya_cmd_status = 0;                // Current status of serial-read
+uint8_t tuya_cmd_checksum = 0;              // Checksum of tuya command
+uint8_t tuya_data_len = 0;                  // Data lenght of command
+
+boolean TuyaSetPower()
+{
+  boolean status = false;
+
+  uint8_t rpower = XdrvMailbox.index;
+  int16_t source = XdrvMailbox.payload;
+
+  if (source != SRC_SWITCH ) {  // ignore to prevent loop from pushing state from faceplate interaction
+
+    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: SetDevicePower.rpower=%d"), rpower);
+    AddLog(LOG_LEVEL_DEBUG);
+
+    Serial.write(0x55); // Tuya header 55AA
+    Serial.write(0xAA);
+    Serial.write(0x00); // version 00
+    Serial.write(0x06); // Tuya command 06
+    Serial.write(0x00);
+    Serial.write(0x05); // following data length 0x05
+    Serial.write(0x01); // relay number 1,2,3
+    Serial.write(0x01);
+    Serial.write(0x00);
+    Serial.write(0x01);
+    Serial.write(rpower); // status
+    Serial.write(0x0D + rpower); // checksum sum of all bytes in packet mod 256
+    Serial.flush();
+
+    status = true;
+  }
+  return status;
+}
+
+void LightSerialDuty(uint8_t duty)
+{
+  if (duty > 0 && !tuya_ignore_dim ) {
+    if (duty < 25) {
+      duty = 25;  // dimming acts odd below 25(10%) - this mirrors the threshold set on the faceplate itself
+    }
+    Serial.write(0x55); // Tuya header 55AA
+    Serial.write(0xAA);
+    Serial.write(0x00); // version 00
+    Serial.write(0x06); // Tuya command 06 - send order
+    Serial.write(0x00);
+    Serial.write(0x08); // following data length 0x08
+    Serial.write(Settings.param[P_TUYA_DIMMER_ID]); // dimmer id
+    Serial.write(0x02); // type=value
+    Serial.write(0x00); // length hi
+    Serial.write(0x04); // length low
+    Serial.write(0x00); //
+    Serial.write(0x00); //
+    Serial.write(0x00); //
+    Serial.write( duty ); // dim value (0-255)
+    Serial.write( byte(Settings.param[P_TUYA_DIMMER_ID] + 19 + duty) ); // checksum:sum of all bytes in packet mod 256
+    Serial.flush();
+
+    snprintf_P(log_data, sizeof(log_data), PSTR( "TYA: Send Serial Packet Dim Value=%d (id=%d)"), duty, Settings.param[P_TUYA_DIMMER_ID]);
+    AddLog(LOG_LEVEL_DEBUG);
+
+  } else {
+    tuya_ignore_dim = false;  // reset flag
+
+    snprintf_P(log_data, sizeof(log_data), PSTR( "TYA: Send Dim Level skipped due to 0 or already set. Value=%d"), duty);
+    AddLog(LOG_LEVEL_DEBUG);
+
+  }
+}
+
+void TuyaPacketProcess()
+{
+  char scmnd[20];
+
+  snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Packet Size=%d"), serial_in_byte_counter);
+  AddLog(LOG_LEVEL_DEBUG);
+
+  if (serial_in_byte_counter == 7 && serial_in_buffer[3] == 14 ) {  // heartbeat packet
+    AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: Heartbeat"));
+  }
+  else if (serial_in_byte_counter == 12 && serial_in_buffer[3] == 7 && serial_in_buffer[5] == 5) {  // on/off packet
+
+    snprintf_P(log_data, sizeof(log_data),PSTR("TYA: Rcvd - %s State"),serial_in_buffer[10]?"On":"Off");
+    AddLog(LOG_LEVEL_DEBUG);
+
+    if((power || Settings.light_dimmer > 0) && (power != serial_in_buffer[10])) {
+      ExecuteCommandPower(1, serial_in_buffer[10], SRC_SWITCH);  // send SRC_SWITCH? to use as flag to prevent loop from inbound states from faceplate interaction
+    }
+  }
+  else if (serial_in_byte_counter == 15 && serial_in_buffer[3] == 7 && serial_in_buffer[5] == 8) {  // dim packet
+
+    snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Rcvd Dim State=%d"), serial_in_buffer[13]);
+    AddLog(LOG_LEVEL_DEBUG);
+
+    tuya_new_dim = round(serial_in_buffer[13] * (100. / 255.));
+    if((power || !Settings.light_dimmer ) && (tuya_new_dim > 0) && (abs(tuya_new_dim - Settings.light_dimmer) > 2)) {
+
+      snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Send CMND_DIMMER=%d"), tuya_new_dim );
+      AddLog(LOG_LEVEL_DEBUG);
+
+      snprintf_P(scmnd, sizeof(scmnd), PSTR(D_CMND_DIMMER " %d"), tuya_new_dim );
+
+      snprintf_P(log_data, sizeof(log_data), PSTR("TYA: Send CMND_DIMMER_STR=%s"), scmnd );
+      AddLog(LOG_LEVEL_DEBUG);
+
+      tuya_ignore_dim = true;
+      ExecuteCommand(scmnd, SRC_SWITCH);
+    }
+  }
+  else if (serial_in_byte_counter == 8 && serial_in_buffer[3] == 5 && serial_in_buffer[5] == 1 && serial_in_buffer[7] == 5 ) {  // reset WiFi settings packet - to do: reset red MCU LED after WiFi is up
+
+    AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: WiFi Reset Rcvd"));
+
+    snprintf_P(scmnd, sizeof(scmnd), D_CMND_WIFICONFIG " 2");
+    ExecuteCommand(scmnd, SRC_BUTTON);
+  }
+}
+
+void TuyaSerialInput()
+{
+  while (Serial.available()) {
+    yield();
+    serial_in_byte = Serial.read();
+
+    //snprintf_P(log_data, sizeof(log_data), PSTR("TYA: serial_in_byte %d, tuya_cmd_status %d, tuya_cmd_checksum %d, tuya_data_len %d, serial_in_byte_counter %d"), serial_in_byte, tuya_cmd_status, tuya_cmd_checksum, tuya_data_len, serial_in_byte_counter);
+    //AddLog(LOG_LEVEL_DEBUG);
+
+    if (serial_in_byte == 0x55) {            // Start TUYA Packet
+      tuya_cmd_status = 1;
+      serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
+      tuya_cmd_checksum += serial_in_byte;
+    }
+    else if (tuya_cmd_status == 1 && serial_in_byte == 0xAA){ // Only packtes with header 0x55AA are valid
+      tuya_cmd_status = 2;
+
+      AddLog_P(LOG_LEVEL_DEBUG, PSTR("TYA: 0x55AA Packet Start"));
+
+      serial_in_byte_counter = 0;
+      serial_in_buffer[serial_in_byte_counter++] = 0x55;
+      serial_in_buffer[serial_in_byte_counter++] = 0xAA;
+      tuya_cmd_checksum = 0xFF;
+    }
+    else if (tuya_cmd_status == 2){
+      if(serial_in_byte_counter == 5){ // Get length of data
+        tuya_cmd_status = 3;
+        tuya_data_len = serial_in_byte;
+      }
+      tuya_cmd_checksum += serial_in_byte;
+      serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
+    }
+    else if ((tuya_cmd_status == 3) && (serial_in_byte_counter == (6 + tuya_data_len)) && (tuya_cmd_checksum == serial_in_byte)){ // Compare checksum and process packet
+      serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
+
+      snprintf_P(log_data, sizeof(log_data), PSTR("TYA: 0x55 Packet End: \""));
+      for (int i = 0; i < serial_in_byte_counter; i++) {
+        snprintf_P(log_data, sizeof(log_data), PSTR("%s%02x"), log_data, serial_in_buffer[i]);
+      }
+      snprintf_P(log_data, sizeof(log_data), PSTR("%s\""), log_data);
+      AddLog(LOG_LEVEL_DEBUG);
+
+      TuyaPacketProcess();
+      serial_in_byte_counter = 0;
+      tuya_cmd_status = 0;
+      tuya_cmd_checksum = 0;
+      tuya_data_len = 0;
+    }                               // read additional packets from TUYA
+    else if(serial_in_byte_counter < INPUT_BUFFER_SIZE -1) {  // add char to string if it still fits
+      serial_in_buffer[serial_in_byte_counter++] = serial_in_byte;
+      tuya_cmd_checksum += serial_in_byte;
+    } else {
+      serial_in_byte_counter = 0;
+      tuya_cmd_status = 0;
+      tuya_cmd_checksum = 0;
+      tuya_data_len = 0;
+    }
+  }
+}
+
+boolean TuyaModuleSelected()
+{
+  baudrate = 9600;
+  light_type = LT_SERIAL;
+  return true;
+}
+
+void TuyaInit()
+{
+  if (!Settings.param[P_TUYA_DIMMER_ID]) {
+    Settings.param[P_TUYA_DIMMER_ID] = TUYA_DIMMER_ID;
+  }
+  Serial.setDebugOutput(false);
+  ClaimSerial();
+
+  // Get current status of MCU
+  snprintf_P(log_data, sizeof(log_data), "TYA: Request MCU state");
+  AddLog(LOG_LEVEL_DEBUG);
+  Serial.write(0x55); // header 55AA
+  Serial.write(0xAA);
+  Serial.write(0x00); // version 00
+  Serial.write(0x08); // command 08 - get status
+  Serial.write(0x00);
+  Serial.write(0x00); // following data length 0x00
+  Serial.write(0x07); // checksum:sum of all bytes in packet mod 256
+  Serial.flush();
+}
+
+/*********************************************************************************************\
+ * Interface
+\*********************************************************************************************/
+
+#define XDRV_16
+
+boolean Xdrv16(byte function)
+{
+  boolean result = false;
+
+  if (TUYA_DIMMER == Settings.module) {
+    switch (function) {
+      case FUNC_MODULE_INIT:
+        result = TuyaModuleSelected();
+        break;
+      case FUNC_INIT:
+        TuyaInit();
+        break;
+      case FUNC_LOOP:
+        TuyaSerialInput();
+        break;
+      case FUNC_SET_POWER:
+        result = TuyaSetPower();
+        break;
+    }
+  }
+  return result;
+}
+
+#endif  // USE_TUYA_DIMMER
\ No newline at end of file