diff --git a/libraries/SHT31_SW/CHANGELOG.md b/libraries/SHT31_SW/CHANGELOG.md
index afc51a7f..a1bee4af 100644
--- a/libraries/SHT31_SW/CHANGELOG.md
+++ b/libraries/SHT31_SW/CHANGELOG.md
@@ -6,10 +6,14 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.2.0] - 2023-12-09
+- refactor API, follow SHT31
+
+----
+
 ## [0.1.3] - 2023-11-22
 - update readme.md
 
-
 ## [0.1.2] - 2023-07-23
 - update documentation
 - remove commented **SoftwareWire** version => own repo.
diff --git a/libraries/SHT31_SW/README.md b/libraries/SHT31_SW/README.md
index 186494e9..e4eb72f0 100644
--- a/libraries/SHT31_SW/README.md
+++ b/libraries/SHT31_SW/README.md
@@ -59,6 +59,12 @@ Test on UNO
 |  SHT85   |  ~0.2         |  1.5       |  no            |  See SHT31_SWW
 
 
+#### 0.2.0 Breaking change
+
+Version 0.2.0 introduced a breaking change in constructor and begin().
+Parameters have moved from begin() to the constructor.
+
+
 #### Related
 
 These libraries need to be installed to get SHT31_SW working:
diff --git a/libraries/SHT31_SW/SHT31_SW.cpp b/libraries/SHT31_SW/SHT31_SW.cpp
index 57346699..bac5aef9 100644
--- a/libraries/SHT31_SW/SHT31_SW.cpp
+++ b/libraries/SHT31_SW/SHT31_SW.cpp
@@ -1,7 +1,7 @@
 //
 //    FILE: SHT31_SW.cpp
-//  AUTHOR: Rob Tillaart
-// VERSION: 0.1.3
+//  AUTHOR: Rob Tillaart, Gunter Haug
+// VERSION: 0.2.0
 //    DATE: 2019-02-08 (base SHT31 lib)
 // PURPOSE: Arduino library for the SHT31 temperature and humidity sensor
 //          to be used with the SoftWire library instead of (hardware) Wire.
@@ -14,10 +14,10 @@
 #include "SHT31_SW.h"
 
 
-SHT31_SW::SHT31_SW()
+SHT31_SW::SHT31_SW(const uint8_t address,  SoftWire *softWire)
 {
-  _softWire       = NULL;
-  _address        = 0;
+  _address        = address;
+  _softWire       = softWire;
   _lastRead       = 0;
   _rawTemperature = 0;
   _rawHumidity    = 0;
@@ -29,25 +29,17 @@ SHT31_SW::SHT31_SW()
 }
 
 
-bool SHT31_SW::begin(const uint8_t address,  SoftWire *softWire)
+bool SHT31_SW::begin()
 {
-  if ((address != 0x44) && (address != 0x45))
+  if ((_address != 0x44) && (_address != 0x45))
   {
     return false;
   }
-  _address  = address;
-  _softWire = softWire;
   _softWire->begin();
   return reset();
 }
 
 
-bool SHT31_SW::begin(SoftWire *softWire)
-{
-  return begin(SHT_DEFAULT_ADDRESS, softWire);
-}
-
-
 bool SHT31_SW::isConnected()
 {
   _softWire->beginTransmission(_address);
diff --git a/libraries/SHT31_SW/SHT31_SW.h b/libraries/SHT31_SW/SHT31_SW.h
index b35030ca..f209a0c1 100644
--- a/libraries/SHT31_SW/SHT31_SW.h
+++ b/libraries/SHT31_SW/SHT31_SW.h
@@ -2,7 +2,7 @@
 //
 //    FILE: SHT31_SW.h
 //  AUTHOR: Rob Tillaart, Gunter Haug
-// VERSION: 0.1.3
+// VERSION: 0.2.0
 //    DATE: 2019-02-08 (base SHT31 lib)
 // PURPOSE: Arduino library for the SHT31 temperature and humidity sensor
 //          to be used with the SoftWire library instead of (hardware) Wire.
@@ -12,7 +12,7 @@
 //          https://github.com/RobTillaart/SHT31
 
 
-#define SHT31_SW_LIB_VERSION             (F("0.1.3"))
+#define SHT31_SW_LIB_VERSION             (F("0.2.0"))
 
 
 #include "Arduino.h"
@@ -23,11 +23,8 @@
 class SHT31_SW : public SHT31
 {
 public:
-  SHT31_SW();
-
-  //  use SHT_DEFAULT_ADDRESS
-  bool begin(const uint8_t address,  SoftWire *wire);
-  bool begin(SoftWire *wire);
+  SHT31_SW(uint8_t address, SoftWire *wire);
+  bool begin();
 
   //  check if sensor is reachable over I2C
   bool isConnected();
diff --git a/libraries/SHT31_SW/examples/SHT31_I2Cspeed/SHT31_I2Cspeed.ino b/libraries/SHT31_SW/examples/SHT31_I2Cspeed/SHT31_I2Cspeed.ino
index 0e028ec4..a19f5e80 100644
--- a/libraries/SHT31_SW/examples/SHT31_I2Cspeed/SHT31_I2Cspeed.ino
+++ b/libraries/SHT31_SW/examples/SHT31_I2Cspeed/SHT31_I2Cspeed.ino
@@ -16,7 +16,7 @@ SoftWire sw(6, 7);
 uint32_t start;
 uint32_t stop;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -27,8 +27,8 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
   uint16_t stat = sht.readStatus();
   Serial.print(stat, HEX);
@@ -58,7 +58,7 @@ void test()
   Serial.print(sht.getTemperature(), 1);
   Serial.print("\t");
   Serial.println(sht.getHumidity(), 1);
-  delay(100);
+  delay(1000);
 }
 
 
diff --git a/libraries/SHT31_SW/examples/SHT31_async/SHT31_async.ino b/libraries/SHT31_SW/examples/SHT31_async/SHT31_async.ino
index 70fa6f69..de9e8cf8 100644
--- a/libraries/SHT31_SW/examples/SHT31_async/SHT31_async.ino
+++ b/libraries/SHT31_SW/examples/SHT31_async/SHT31_async.ino
@@ -17,7 +17,7 @@ uint32_t start;
 uint32_t stop;
 uint32_t cnt;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -28,8 +28,8 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
   uint16_t stat = sht.readStatus();
   Serial.print(stat, HEX);
@@ -45,9 +45,9 @@ void loop()
   if (sht.dataReady())
   {
     start = micros();
-    bool success  = sht.readData();   // default = true = fast
+    bool success  = sht.readData();   //  default = true = fast
     stop = micros();
-    sht.requestData();                // request for next sample
+    sht.requestData();                //  request for next sample
 
     Serial.print("\t");
     Serial.print(stop - start);
@@ -66,8 +66,8 @@ void loop()
       cnt = 0;
     }
   }
-  cnt++; // simulate other activity
+  cnt++;  //  simulate other activity
 }
 
 
-// -- END OF FILE --
+//  -- END OF FILE --
diff --git a/libraries/SHT31_SW/examples/SHT31_demo/SHT31_demo.ino b/libraries/SHT31_SW/examples/SHT31_demo/SHT31_demo.ino
index 52e3698c..75f18059 100644
--- a/libraries/SHT31_SW/examples/SHT31_demo/SHT31_demo.ino
+++ b/libraries/SHT31_SW/examples/SHT31_demo/SHT31_demo.ino
@@ -16,7 +16,7 @@ SoftWire sw(6, 7);
 uint32_t start;
 uint32_t stop;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -28,7 +28,7 @@ void setup()
 
   sw.begin();
   sw.setClock(100000);
-  sht.begin(SHT31_ADDRESS, &sw);
+  sht.begin();
 
   Serial.print("CON:\t");
   Serial.println(sht.isConnected());
diff --git a/libraries/SHT31_SW/examples/SHT31_heater/SHT31_heater.ino b/libraries/SHT31_SW/examples/SHT31_heater/SHT31_heater.ino
index a260ea69..c930aeed 100644
--- a/libraries/SHT31_SW/examples/SHT31_heater/SHT31_heater.ino
+++ b/libraries/SHT31_SW/examples/SHT31_heater/SHT31_heater.ino
@@ -16,7 +16,7 @@ SoftWire sw(6, 7);
 uint32_t start;
 uint32_t stop;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 uint16_t status;
 
 
@@ -28,10 +28,10 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
-  sht.setHeatTimeout(30);  // heater timeout 30 seconds, just for demo.
+  sht.setHeatTimeout(30);  //  heater timeout 30 seconds, just for demo.
 
   status = sht.readStatus();
   printHeaterStatus(status);
@@ -71,4 +71,4 @@ void printHeaterStatus(uint16_t status)
 }
 
 
-// -- END OF FILE --
+//  -- END OF FILE --
diff --git a/libraries/SHT31_SW/examples/SHT31_isConnected/SHT31_isConnected.ino b/libraries/SHT31_SW/examples/SHT31_isConnected/SHT31_isConnected.ino
index b43589df..fa5cfe7a 100644
--- a/libraries/SHT31_SW/examples/SHT31_isConnected/SHT31_isConnected.ino
+++ b/libraries/SHT31_SW/examples/SHT31_isConnected/SHT31_isConnected.ino
@@ -17,7 +17,7 @@ uint32_t start;
 uint32_t stop;
 uint32_t connectionFails = 0;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -28,8 +28,8 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
   uint16_t stat = sht.readStatus();
   Serial.print(stat, HEX);
diff --git a/libraries/SHT31_SW/examples/SHT31_lastRead/SHT31_lastRead.ino b/libraries/SHT31_SW/examples/SHT31_lastRead/SHT31_lastRead.ino
index a93c44b8..98a1b2a1 100644
--- a/libraries/SHT31_SW/examples/SHT31_lastRead/SHT31_lastRead.ino
+++ b/libraries/SHT31_SW/examples/SHT31_lastRead/SHT31_lastRead.ino
@@ -16,7 +16,7 @@ SoftWire sw(6, 7);
 uint32_t start;
 uint32_t stop;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -27,8 +27,8 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
 
   uint16_t stat = sht.readStatus();
@@ -39,7 +39,7 @@ void setup()
 
 void loop()
 {
-  sht.read();         // default = true/fast       slow = false
+  sht.read();         //  default = true/fast       slow = false
   Serial.print("\t");
   Serial.print(sht.lastRead());
   Serial.print("\t");
@@ -50,5 +50,5 @@ void loop()
 }
 
 
-// -- END OF FILE --
+//  -- END OF FILE --
 
diff --git a/libraries/SHT31_SW/examples/SHT31_rawValues/SHT31_rawValues.ino b/libraries/SHT31_SW/examples/SHT31_rawValues/SHT31_rawValues.ino
index e7f45afc..f9c5e785 100644
--- a/libraries/SHT31_SW/examples/SHT31_rawValues/SHT31_rawValues.ino
+++ b/libraries/SHT31_SW/examples/SHT31_rawValues/SHT31_rawValues.ino
@@ -17,7 +17,7 @@ uint32_t start;
 uint32_t stop;
 uint32_t cnt;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -28,8 +28,8 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
 
   uint16_t stat = sht.readStatus();
@@ -49,9 +49,9 @@ void loop()
   if (sht.dataReady())
   {
     start = micros();
-    bool success  = sht.readData();   // default = true = fast
+    bool success  = sht.readData();   //  default = true = fast
     stop = micros();
-    sht.requestData();                // request for next sample
+    sht.requestData();                //  request for next sample
 
     Serial.print("\t");
     Serial.print(stop - start);
@@ -66,19 +66,23 @@ void loop()
       rawHumidity = sht.getRawHumidity();
       Serial.print(rawTemperature, HEX);
       Serial.print(" = ");
-      Serial.print(rawTemperature * (175.0 / 65535) - 45, 1); // This formula comes from page 14 of the SHT31 datasheet
+
+      // This formula comes from page 14 of the SHT31 datasheet
+      Serial.print(rawTemperature * (175.0 / 65535) - 45, 1);
       Serial.print("°C\t");
       Serial.print(sht.getRawHumidity(), HEX);
       Serial.print(" = ");
-      Serial.print(rawHumidity * (100.0 / 65535), 1); // This formula comes from page 14 of the SHT31 datasheet
+
+      // This formula comes from page 14 of the SHT31 datasheet
+      Serial.print(rawHumidity * (100.0 / 65535), 1);
       Serial.print("%\t");
       Serial.println(cnt);
       cnt = 0;
     }
   }
-  cnt++; // simulate other activity
+  cnt++;  //  simulate other activity
 }
 
 
-// -- END OF FILE --
+//  -- END OF FILE --
 
diff --git a/libraries/SHT31_SW/examples/SHT31_slowRead/SHT31_slowRead.ino b/libraries/SHT31_SW/examples/SHT31_slowRead/SHT31_slowRead.ino
index 9a11ec93..7feafee5 100644
--- a/libraries/SHT31_SW/examples/SHT31_slowRead/SHT31_slowRead.ino
+++ b/libraries/SHT31_SW/examples/SHT31_slowRead/SHT31_slowRead.ino
@@ -16,7 +16,7 @@ SoftWire sw(6, 7);
 uint32_t start;
 uint32_t stop;
 
-SHT31_SW sht;
+SHT31_SW sht(SHT31_ADDRESS, &sw);
 
 
 void setup()
@@ -27,8 +27,8 @@ void setup()
   Serial.println(SHT31_SW_LIB_VERSION);
 
   sw.begin();
-  sht.begin(SHT31_ADDRESS, &sw);
   sw.setClock(100000);
+  sht.begin();
 
   uint16_t stat = sht.readStatus();
   Serial.print(stat, HEX);
diff --git a/libraries/SHT31_SW/library.json b/libraries/SHT31_SW/library.json
index f1bd83c5..b33107b3 100644
--- a/libraries/SHT31_SW/library.json
+++ b/libraries/SHT31_SW/library.json
@@ -31,7 +31,7 @@
       "version": "^1.1.2"
     }
   ],
-  "version": "0.1.3",
+  "version": "0.2.0",
   "license": "MIT",
   "frameworks": "arduino",
   "platforms": "*",
diff --git a/libraries/SHT31_SW/library.properties b/libraries/SHT31_SW/library.properties
index 6bb8107a..dac6b2e7 100644
--- a/libraries/SHT31_SW/library.properties
+++ b/libraries/SHT31_SW/library.properties
@@ -1,5 +1,5 @@
 name=SHT31_SW
-version=0.1.3
+version=0.2.0
 author=Rob Tillaart <rob.tillaart@gmail.com>, Gunter Haug
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino library for the I2C SHT31 temperature and humidity sensor
diff --git a/libraries/SHT31_SW/test/unit_test_001.cpp b/libraries/SHT31_SW/test/unit_test_001.cpp
index ec4006fe..fc66232c 100644
--- a/libraries/SHT31_SW/test/unit_test_001.cpp
+++ b/libraries/SHT31_SW/test/unit_test_001.cpp
@@ -36,7 +36,7 @@
 #include "SHT31_SW.h"
 
 
-int expect;  // TODO needed as there seems a problem with 8 bit comparisons (char?)
+int expect;  //  TODO needed as there seems a problem with 8 bit comparisons (char?)
 
 uint32_t start, stop;