diff --git a/I2C_eeprom.cpp b/I2C_eeprom.cpp
index d71d4d0..977cde4 100644
--- a/I2C_eeprom.cpp
+++ b/I2C_eeprom.cpp
@@ -1,7 +1,7 @@
 //
 //    FILE: I2C_eeprom.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 1.4.2
+// VERSION: 1.4.3
 // PURPOSE: Arduino Library for external I2C EEPROM 24LC256 et al.
 //     URL: https://github.com/RobTillaart/I2C_EEPROM.git
 //
@@ -37,6 +37,7 @@
 //  1.4.1   2021-01-28  fixed addressing bug 24LC04/08/16 equivalents from ST e.g. m24c08w
 //                      add Wire1..WireN;
 //  1.4.2   2021-01-31  add updateBlock()
+//  1.4.3   2021-05-05  adjust buffer size AVR / ESP +rename
 
 
 #include <I2C_eeprom.h>
@@ -56,9 +57,11 @@
 
 //  TWI buffer needs max 2 bytes for eeprom address
 //  1 byte for eeprom register address is available in txbuffer
-//  NOTE this is typical on an UNO.
-//  TODO investigate
-#define I2C_TWIBUFFERSIZE           30
+#if defined(ESP32) || defined(ESP8266)
+#define I2C_BUFFERSIZE           128
+#else
+#define I2C_BUFFERSIZE           30   //  AVR, STM 
+#endif
 
 
 I2C_eeprom::I2C_eeprom(const uint8_t deviceAddress, TwoWire *wire)
@@ -120,8 +123,8 @@ int I2C_eeprom::writeByte(const uint16_t memoryAddress, const uint8_t data)
 
 int I2C_eeprom::setBlock(const uint16_t memoryAddress, const uint8_t data, const uint16_t length)
 {
-  uint8_t buffer[I2C_TWIBUFFERSIZE];
-  for (uint8_t i = 0; i < I2C_TWIBUFFERSIZE; i++)
+  uint8_t buffer[I2C_BUFFERSIZE];
+  for (uint8_t i = 0; i < I2C_BUFFERSIZE; i++)
   {
     buffer[i] = data;
   }
@@ -152,7 +155,7 @@ uint16_t I2C_eeprom::readBlock(const uint16_t memoryAddress, uint8_t* buffer, co
   uint16_t rv = 0;
   while (len > 0)
   {
-    uint8_t cnt = I2C_TWIBUFFERSIZE;
+    uint8_t cnt = I2C_BUFFERSIZE;
     if (cnt > len) cnt = len;
     rv     += _ReadBlock(addr, buffer, cnt);
     addr   += cnt;
@@ -177,8 +180,8 @@ int I2C_eeprom::updateBlock(const uint16_t memoryAddress, const uint8_t* buffer,
   uint16_t rv = 0;
   while (len > 0)
   {
-    uint8_t buf[I2C_TWIBUFFERSIZE];
-    uint8_t cnt = I2C_TWIBUFFERSIZE;
+    uint8_t buf[I2C_BUFFERSIZE];
+    uint8_t cnt = I2C_BUFFERSIZE;
     
     if (cnt > len) cnt = len;
     rv     += _ReadBlock(addr, buf, cnt);
@@ -281,7 +284,7 @@ int I2C_eeprom::_pageBlock(const uint16_t memoryAddress, const uint8_t* buffer,
   {
     uint8_t bytesUntilPageBoundary = this->_pageSize - addr % this->_pageSize;
 
-    uint8_t cnt = I2C_TWIBUFFERSIZE;
+    uint8_t cnt = I2C_BUFFERSIZE;
     if (cnt > len) cnt = len;
     if (cnt > bytesUntilPageBoundary) cnt = bytesUntilPageBoundary;
 
@@ -316,7 +319,7 @@ void I2C_eeprom::_beginTransmission(const uint16_t memoryAddress)
 }
 
 
-// pre: length <= this->_pageSize  && length <= I2C_TWIBUFFERSIZE;
+// pre: length <= this->_pageSize  && length <= I2C_BUFFERSIZE;
 // returns 0 = OK otherwise error
 int I2C_eeprom::_WriteBlock(const uint16_t memoryAddress, const uint8_t* buffer, const uint8_t length)
 {
diff --git a/I2C_eeprom.h b/I2C_eeprom.h
index 0c139c7..e0323d5 100644
--- a/I2C_eeprom.h
+++ b/I2C_eeprom.h
@@ -2,7 +2,7 @@
 //
 //    FILE: I2C_eeprom.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 1.4.2
+// VERSION: 1.4.3
 // PURPOSE: Arduino Library for external I2C EEPROM 24LC256 et al.
 //     URL: https://github.com/RobTillaart/I2C_EEPROM.git
 //
@@ -13,7 +13,7 @@
 #include "Wire.h"
 
 
-#define I2C_EEPROM_VERSION          (F("1.4.2"))
+#define I2C_EEPROM_VERSION          (F("1.4.3"))
 
 
 #define I2C_DEVICESIZE_24LC512      65536
diff --git a/library.json b/library.json
index 647c980..9f3d000 100644
--- a/library.json
+++ b/library.json
@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/I2C_EEPROM.git"
   },
-  "version":"1.4.2",
+  "version":"1.4.3",
   "frameworks": "arduino",
   "platforms": "*"
 }
diff --git a/library.properties b/library.properties
index 02e2b52..09e17f7 100644
--- a/library.properties
+++ b/library.properties
@@ -1,5 +1,5 @@
 name=I2C_EEPROM
-version=1.4.2
+version=1.4.3
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Library for I2C EEPROMS