diff --git a/README.md b/README.md
index 20b7d95..8b82b80 100644
--- a/README.md
+++ b/README.md
@@ -51,16 +51,12 @@ Set the functional mode, Tos and Thyst: if that functionally desired.
 **Connections**
 
 The Sensor uses I2C for communication's, data is outputted to a PC.
-Pins and I2C port can be set in the main.cpp. Default is I2C0 and GPIO16(data) GPIO17(clock).
-If you want to use the other I2C port (I2C1) in addition to changing in the main.ccp,
-The user must change it in library (lm75.h) as well:
-* i2c_inst_t *i2c = i2c0 to i2c_inst_t *i2c = i2c1
-Could not find a way around this.
+Pins and I2C port(I2C0 or I2C1) can be set in the main.cpp. Default is I2C0 and GPIO16(data) GPIO17(clock).
  
 **Files**
 
 The main.cpp contains tests showing library functions
-There is also the library files(LM75A.cpp and LM75A.h),
+There is also the library files(LM75A.cpp and LM75A.hpp),
 
 **Output**
 
diff --git a/extra/doc/CHANGELOG.md b/extra/doc/CHANGELOG.md
index dff3768..59c8f48 100644
--- a/extra/doc/CHANGELOG.md
+++ b/extra/doc/CHANGELOG.md
@@ -2,5 +2,7 @@
 
 * version 1.0.0 September 2022
 	* first release
+* version 1.0.1 December 2022	
+	* Change so user can pick any I2C interface (IC20 or IC21)
 
 
diff --git a/include/lm75/lm75.h b/include/lm75/lm75.hpp
similarity index 85%
rename from include/lm75/lm75.h
rename to include/lm75/lm75.hpp
index 3291d04..55a7c39 100644
--- a/include/lm75/lm75.h
+++ b/include/lm75/lm75.hpp
@@ -1,6 +1,6 @@
 /*
  * Project Name: Library for the LM75A temperature sensor by NXP and Texas Instruments.
- * File: lm75.h
+ * File: lm75.hpp
  * Description: library header file
  * Author: Gavin Lyons.
  * IDE:  Rpi=PICo rp2040 C++
@@ -53,7 +53,11 @@ class LIB_LM75A
 {
 private:
 	// Private variables
-	uint8_t _i2cAddress;
+	uint8_t _i2cAddress; 
+	i2c_inst_t *i2c = i2c0;  // i2C port number, i2c1 or i2c0
+    uint8_t _SDataPin;
+    uint8_t _SClkPin;
+    uint16_t _CLKSpeed = 100; //I2C bus speed in khz typically 100-400
 
 	// Private functions
 	uint8_t read8bitRegister(const uint8_t reg);
@@ -64,11 +68,11 @@ class LIB_LM75A
 public:
 
 	// Constructor
-    LIB_LM75A(uint8_t address);
+    LIB_LM75A(uint8_t address, i2c_inst_t* i2c_type, uint8_t SDApin, uint8_t  SCLKpin, uint16_t CLKspeed);
 
 	//I2c init & deinit
-	void initLM75A(i2c_inst_t* i2c_type, uint8_t  SDApin, uint8_t  SCLKpin, uint16_t CLKspeed);
-	void deinitLM75A(i2c_inst_t* i2c_type);
+	void initLM75A();
+	void deinitLM75A();
 
 	// Power management
 	void shutdown();
@@ -96,8 +100,7 @@ class LIB_LM75A
 	uint8_t getConfig();
 	float getProdId();
 
-    i2c_inst_t *i2c = i2c0;  // i2C port number
-    int16_t return_value = 0; //return value
+	int16_t return_value = 0; //return value, I2C routines
 };
 
 #endif
diff --git a/src/lm75/lm75.cpp b/src/lm75/lm75.cpp
index 5cef26f..1a4a36d 100644
--- a/src/lm75/lm75.cpp
+++ b/src/lm75/lm75.cpp
@@ -10,14 +10,22 @@
  */
 
 #include "pico/stdlib.h"
-#include "../include/lm75/lm75.h"
+#include "../include/lm75/lm75.hpp"
 
 
 // Constructor
-// Param 1 I2C address (7-bit)
-LIB_LM75A::LIB_LM75A(uint8_t i2cAddress)
+// Param1 : I2C address (7-bit)
+// Param2 : I2C instance of port IC20 or I2C1
+// Param3 : I2C Data pin
+// Param4 : I2C Clock pin
+// Param5 : I2C Bus Clock speed in KHz. Typically 100-400
+LIB_LM75A::LIB_LM75A(uint8_t i2cAddress, i2c_inst_t* i2c_type, uint8_t SDApin, uint8_t SCLKpin, uint16_t CLKspeed)
 {
-	_i2cAddress = i2cAddress;
+    _i2cAddress = i2cAddress;
+    _SClkPin = SCLKpin;
+    _SDataPin = SDApin;
+    _CLKSpeed = CLKspeed;
+     i2c = i2c_type; 
 }
 
 // Power management
@@ -25,15 +33,15 @@ LIB_LM75A::LIB_LM75A(uint8_t i2cAddress)
 // Func Desc : enter Shutdown mode : 4 μA (Typical) current draw.
 void LIB_LM75A::shutdown()
 {
-	uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11111110) | 0b1);
+    uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11111110) | 0b1);
 }
 
 // Func Desc : exit Shutdown mode for  Operating  mode: 280 μA (Typical)
 void LIB_LM75A::wakeup()
 {
-	uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, config & 0b11111110);
+    uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, config & 0b11111110);
 }
 // Fucn Desc get power mode
 // Return bool
@@ -41,7 +49,7 @@ void LIB_LM75A::wakeup()
 // 0 operating mode
 bool LIB_LM75A::isShutdown()
 {
-	return (read8bitRegister(LM75A_REGISTER_CONFIG) & 0b1) == 1;	
+    return (read8bitRegister(LM75A_REGISTER_CONFIG) & 0b1) == 1;	
 }
 
 
@@ -51,84 +59,84 @@ bool LIB_LM75A::isShutdown()
 // returns float
 float LIB_LM75A::getTemperature()
 {
-	uint16_t result;
-	if (!read16bitRegister(LM75A_REGISTER_TEMP, result))
-	{
-		return LM75A_INVALID_TEMPERATURE;
-	}
-	return (float)result / 256.0f;
+    uint16_t result;
+    if (!read16bitRegister(LM75A_REGISTER_TEMP, result))
+    {
+        return LM75A_INVALID_TEMPERATURE;
+    }
+    return (float)result / 256.0f;
 }
 
 // Get temperature Farenheit(
 // returns float
 float LIB_LM75A::getTemperatureInFarenheit()
 {
-	return getTemperature() * 1.8f + 32.0f;
+    return getTemperature() * 1.8f + 32.0f;
 }
 
 // Configuration functions
 
 float LIB_LM75A::getHysterisisTemperature()
 {
-	uint16_t result;
-	if (!read16bitRegister(LM75A_REGISTER_THYST, result))
-	{
-		return LM75A_INVALID_TEMPERATURE;
-	}
-	return (float)result / 256.0f;
+    uint16_t result;
+    if (!read16bitRegister(LM75A_REGISTER_THYST, result))
+    {
+        return LM75A_INVALID_TEMPERATURE;
+    }
+    return (float)result / 256.0f;
 }
 
 FaultQueueValue LIB_LM75A::getFaultQueueValue()
 {
-	return (FaultQueueValue)(read8bitRegister(LM75A_REGISTER_CONFIG) & 0b00011000);
+    return (FaultQueueValue)(read8bitRegister(LM75A_REGISTER_CONFIG) & 0b00011000);
 }
 
 float LIB_LM75A::getOSTripTemperature()
 {
-	uint16_t result;
-	if (!read16bitRegister(LM75A_REGISTER_TOS, result))
-	{
-		return LM75A_INVALID_TEMPERATURE;
-	}
-	return (float)result / 256.0f;
+    uint16_t result;
+    if (!read16bitRegister(LM75A_REGISTER_TOS, result))
+    {
+        return LM75A_INVALID_TEMPERATURE;
+    }
+    return (float)result / 256.0f;
 }
 
 OsPolarity LIB_LM75A::getOsPolarity()
 {
-	return (OsPolarity)(read8bitRegister(LM75A_REGISTER_CONFIG) & 0b100);
+    return (OsPolarity)(read8bitRegister(LM75A_REGISTER_CONFIG) & 0b100);
 }
 
 DeviceMode LIB_LM75A::getDeviceMode()
 {
-	return (DeviceMode)(read8bitRegister(LM75A_REGISTER_CONFIG) & 0b010);
+    return (DeviceMode)(read8bitRegister(LM75A_REGISTER_CONFIG) & 0b010);
 }
 
 void LIB_LM75A::setHysterisisTemperature(float temperature)
 {
-	write16bitRegister(LM75A_REGISTER_THYST, temperature * 256);
+    write16bitRegister(LM75A_REGISTER_THYST, temperature * 256);
 }
 
 void LIB_LM75A::setOsTripTemperature(float temperature)
 {
-	write16bitRegister(LM75A_REGISTER_TOS, temperature * 256);
+    write16bitRegister(LM75A_REGISTER_TOS, temperature * 256);
 }
 
 void LIB_LM75A::setFaultQueueValue(FaultQueueValue value)
 {
-	uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11100111) | value);
+    uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11100111) | value);
 }
 
 void LIB_LM75A::setOsPolarity(OsPolarity polarity)
 {
-	uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11111011) | polarity);
+    uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11111011) | polarity);
 }
 
 void LIB_LM75A::setDeviceMode(DeviceMode deviceMode)
 {
-	uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11111101) | deviceMode);
+    uint8_t config = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, (config & 0b11111101) | deviceMode);
 }
 
 
@@ -137,114 +145,113 @@ void LIB_LM75A::setDeviceMode(DeviceMode deviceMode)
 // Returns 1 for success 0 if not.
 bool LIB_LM75A::isConnected()
 {
-	uint8_t oldValue = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, 0x0f);
-	uint8_t newValue = read8bitRegister(LM75A_REGISTER_CONFIG);
-	write8bitRegister(LM75A_REGISTER_CONFIG, oldValue);
-	return newValue == 0x0f;
+    uint8_t oldValue = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, 0x0f);
+    uint8_t newValue = read8bitRegister(LM75A_REGISTER_CONFIG);
+    write8bitRegister(LM75A_REGISTER_CONFIG, oldValue);
+    return newValue == 0x0f;
 }
 
 // Func Desc :  reads config register
 // Returns Byte with values of config register
 uint8_t LIB_LM75A::getConfig()
 {
-	return read8bitRegister(LM75A_REGISTER_CONFIG);
+    return read8bitRegister(LM75A_REGISTER_CONFIG);
 }
 
 // Func Desc :  reads value of product ID register
 float LIB_LM75A::getProdId()
 {
-	uint8_t value = read8bitRegister(LM75A_REGISTER_PRODID);
-	return (float)(value >> 4) + (value & 0x0F) / 10.0f;
+    uint8_t value = read8bitRegister(LM75A_REGISTER_PRODID);
+    return (float)(value >> 4) + (value & 0x0F) / 10.0f;
 } 
 
 // *************** Private function  ************************
 
 uint8_t LIB_LM75A::read8bitRegister(const uint8_t reg)
 {
-	uint8_t result;
-	uint8_t BufTx[1];
-	BufTx[0] = reg;
-
-	return_value = i2c_write_blocking(i2c, _i2cAddress, BufTx, 1 , true);
-	if (return_value < 1)
-	{
-		return 0xFF;
-	}
-
-	return_value =  i2c_read_blocking(i2c, _i2cAddress, &result, 1, false); 	
-	if (return_value < 1)
-	{
-		return 0xFF;
-	}
-	return result;
+    uint8_t result;
+    uint8_t BufTx[1];
+    BufTx[0] = reg;
+
+    return_value = i2c_write_blocking(i2c, _i2cAddress, BufTx, 1 , true);
+    if (return_value < 1)
+    {
+        return 0xFF;
+    }
+
+    return_value =  i2c_read_blocking(i2c, _i2cAddress, &result, 1, false); 	
+    if (return_value < 1)
+    {
+        return 0xFF;
+    }
+    return result;
 }
 
 bool LIB_LM75A::read16bitRegister(const uint8_t reg, uint16_t& response)
 {
-	uint8_t bufRX[3];
-	uint8_t bufTX[1];
-	bufTX[0] = reg;
-
-	return_value = i2c_write_blocking(i2c, _i2cAddress, bufTX, 1 , true);
-	if (return_value < 1)
-	{
-		return false;
-	}
-
-	return_value =  i2c_read_blocking(i2c, _i2cAddress, bufRX, 2, false); 
-	if (return_value < 1)
-	{
-		return false;
-	}
-	
-	response = bufRX[0] << 8 | bufRX[1];
-	return true;
+    uint8_t bufRX[3];
+    uint8_t bufTX[1];
+    bufTX[0] = reg;
+
+    return_value = i2c_write_blocking(i2c, _i2cAddress, bufTX, 1 , true);
+    if (return_value < 1)
+    {
+        return false;
+    }
+
+    return_value =  i2c_read_blocking(i2c, _i2cAddress, bufRX, 2, false); 
+    if (return_value < 1)
+    {
+        return false;
+    }
+    
+    response = bufRX[0] << 8 | bufRX[1];
+    return true;
 }
 
 bool LIB_LM75A::write16bitRegister(const uint8_t reg, const uint16_t value)
 {
-	uint8_t bufTX[3];
-	bufTX[0] = reg;
-	bufTX[1] = value >> 8;
-	bufTX[2] = value;
-		
-	return_value = i2c_write_blocking(i2c, _i2cAddress, bufTX, 3 , false);
-	if (return_value < 1)
-	{
-		return false;
-	}
-
-	return true;
+    uint8_t bufTX[3];
+    bufTX[0] = reg;
+    bufTX[1] = value >> 8;
+    bufTX[2] = value;
+        
+    return_value = i2c_write_blocking(i2c, _i2cAddress, bufTX, 3 , false);
+    if (return_value < 1)
+    {
+        return false;
+    }
+
+    return true;
 }
 
 bool LIB_LM75A::write8bitRegister(const uint8_t reg, const uint8_t value)
 {
-	uint8_t bufTX[2];
-	bufTX[0] = reg;
-	bufTX[1] = value;
-
-	return_value = i2c_write_blocking(i2c, _i2cAddress, bufTX, 2 ,false);
-	if (return_value < 1)
-	{
-		return false;
-	}
-	return true;
+    uint8_t bufTX[2];
+    bufTX[0] = reg;
+    bufTX[1] = value;
+
+    return_value = i2c_write_blocking(i2c, _i2cAddress, bufTX, 2 ,false);
+    if (return_value < 1)
+    {
+        return false;
+    }
+    return true;
 }
 
-void LIB_LM75A::initLM75A(i2c_inst_t* i2c_type, uint8_t SDApin, uint8_t SCLKpin, uint16_t CLKspeed)
+void LIB_LM75A::initLM75A()
 {
-	i2c_inst_t *i2c = i2c_type;
-	//init I2C
-	i2c_init(i2c, CLKspeed * 1000);
-	gpio_set_function(SDApin, GPIO_FUNC_I2C);
-    gpio_set_function(SCLKpin, GPIO_FUNC_I2C);
-	gpio_pull_up(SDApin);
-    gpio_pull_up(SCLKpin);
+    gpio_set_function(_SDataPin, GPIO_FUNC_I2C);
+    gpio_set_function(_SClkPin, GPIO_FUNC_I2C);
+    gpio_pull_up(_SDataPin);
+    gpio_pull_up(_SClkPin);
+    i2c_init(i2c, _CLKSpeed * 1000);
 }
 
-void LIB_LM75A::deinitLM75A(i2c_inst_t* i2c_type)
+void LIB_LM75A::deinitLM75A()
 {
-	i2c_inst_t *i2c = i2c_type;
-	i2c_deinit(i2c); 	
+    gpio_set_function(_SDataPin, GPIO_FUNC_NULL);
+    gpio_set_function(_SClkPin, GPIO_FUNC_NULL);
+    i2c_deinit(i2c); 	
 }
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 5cdd277..817791a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -12,7 +12,7 @@
 // *** Libraries ***
 #include <stdio.h>
 #include "pico/stdlib.h"
-#include "lm75/lm75.h"
+#include "lm75/lm75.hpp"
 
 // *** Mode select ***
 // mode 1 or mode 2
@@ -20,7 +20,7 @@
 //#define LIB_TEST // Mode 2 :: Full library test example
 
 // *** Globals ***
-LIB_LM75A lm75a(LM75A_DEFAULT_ADDRESS);
+LIB_LM75A lm75a(LM75A_DEFAULT_ADDRESS, i2c0, 16, 17, 100);
 uint8_t is_connected = 0; // test control
 uint16_t test_count = 0 ;   // test control
 
@@ -59,11 +59,10 @@ DeviceMode newDeviceMode = DeviceMode::DEVICE_MODE_INTERRUPT;
 // *** Main ***
 int main()
 {
-  stdio_init_all();              // Initialize chosen serial port
-  lm75a.initLM75A(i2c0, 16, 17, 100); // initLM75A(port, data pin, clock pin, clock speed(KHZ));
-  
+  stdio_init_all(); // Initialize chosen serial port
   busy_wait_ms(1000);
   printf("LM75 : Start!\r\n");
+  lm75a.initLM75A(); 
   
   // Check for connection
   is_connected = lm75a.isConnected();