diff --git a/src/display.cpp b/src/display.cpp
index bfc55f05..ba71a544 100644
--- a/src/display.cpp
+++ b/src/display.cpp
@@ -4,7 +4,7 @@
 #include "globals.h"
 #include <esp_spi_flash.h> // needed for reading ESP32 chip attributes
 
-HAS_DISPLAY u8x8(OLED_RST, OLED_SCL, OLED_SDA);
+HAS_DISPLAY u8x8(OLED_RST, I2C_SCL, I2C_SDA);
 
 // helper string for converting LoRa spread factor values
 #if defined(CFG_eu868)
diff --git a/src/hal/generic.h b/src/hal/generic.h
index bedff5e8..d5863038 100644
--- a/src/hal/generic.h
+++ b/src/hal/generic.h
@@ -34,5 +34,5 @@
 
 // pin definitions for I2C interface of OLED Display
 #define OLED_RST GPIO_NUM_16 // SSD1306 RST
-#define OLED_SDA GPIO_NUM_4  // SD1306 D1+D2
-#define OLED_SCL GPIO_NUM_15 // SD1306 D0
\ No newline at end of file
+#define I2C_SDA GPIO_NUM_4  // SD1306 D1+D2
+#define I2C_SCL GPIO_NUM_15 // SD1306 D0
\ No newline at end of file
diff --git a/src/hal/heltec.h b/src/hal/heltec.h
index 2671fac8..44316c63 100644
--- a/src/hal/heltec.h
+++ b/src/hal/heltec.h
@@ -22,5 +22,5 @@
 
 // Hardware pin definitions for Heltec LoRa-32 Board with OLED SSD1306 I2C Display
 #define OLED_RST GPIO_NUM_16 // ESP32 GPIO16 (Pin16) -- SD1306 RST
-#define OLED_SDA GPIO_NUM_4  // ESP32 GPIO4 (Pin4)   -- SD1306 D1+D2
-#define OLED_SCL GPIO_NUM_15 // ESP32 GPIO15 (Pin15) -- SD1306 D0
+#define I2C_SDA GPIO_NUM_4  // ESP32 GPIO4 (Pin4)   -- SD1306 D1+D2
+#define I2C_SCL GPIO_NUM_15 // ESP32 GPIO15 (Pin15) -- SD1306 D0
diff --git a/src/hal/lolin32litelora.h b/src/hal/lolin32litelora.h
index 4275ea00..6427dbcd 100644
--- a/src/hal/lolin32litelora.h
+++ b/src/hal/lolin32litelora.h
@@ -31,8 +31,8 @@
 
 // Hardware pin definitions for LoRaNode32 Board with OLED I2C Display
 #define OLED_RST U8X8_PIN_NONE  // Not reset pin
-#define OLED_SDA 14             // ESP32 GPIO14 (Pin14) -- OLED SDA
-#define OLED_SCL 12             // ESP32 GPIO12 (Pin12) -- OLED SCL
+#define I2C_SDA 14             // ESP32 GPIO14 (Pin14) -- OLED SDA
+#define I2C_SCL 12             // ESP32 GPIO12 (Pin12) -- OLED SCL
 
 // I2C config for Microchip 24AA02E64 DEVEUI unique address
 #define MCP_24AA02E64_I2C_ADDRESS 0x50 // I2C address for the 24AA02E64 
diff --git a/src/hal/lolin32lora.h b/src/hal/lolin32lora.h
index 976092d7..7964a561 100644
--- a/src/hal/lolin32lora.h
+++ b/src/hal/lolin32lora.h
@@ -32,8 +32,8 @@
 
 // Hardware pin definitions for LoRaNode32 Board with OLED I2C Display
 #define OLED_RST U8X8_PIN_NONE  // Not reset pin
-#define OLED_SDA 21             // ESP32 GPIO21 (Pin21) -- OLED SDA
-#define OLED_SCL 22             // ESP32 GPIO22 (Pin22) -- OLED SCL
+#define I2C_SDA 21             // ESP32 GPIO21 (Pin21) -- OLED SDA
+#define I2C_SCL 22             // ESP32 GPIO22 (Pin22) -- OLED SCL
 
 // I2C config for Microchip 24AA02E64 DEVEUI unique address
 #define MCP_24AA02E64_I2C_ADDRESS 0x50 // I2C address for the 24AA02E64 
diff --git a/src/hal/ttgov1.h b/src/hal/ttgov1.h
index fb04cbb0..f64fe380 100644
--- a/src/hal/ttgov1.h
+++ b/src/hal/ttgov1.h
@@ -24,5 +24,5 @@
 
 // Hardware pin definitions for TTGOv1 Board with OLED SSD1306 I2C Display
 #define OLED_RST GPIO_NUM_16 // ESP32 GPIO16 (Pin16) -- SD1306 Reset
-#define OLED_SDA GPIO_NUM_4  // ESP32 GPIO4 (Pin4)   -- SD1306 Data
-#define OLED_SCL GPIO_NUM_15 // ESP32 GPIO15 (Pin15) -- SD1306 Clock
+#define I2C_SDA GPIO_NUM_4  // ESP32 GPIO4 (Pin4)   -- SD1306 Data
+#define I2C_SCL GPIO_NUM_15 // ESP32 GPIO15 (Pin15) -- SD1306 Clock
diff --git a/src/hal/ttgov2.h b/src/hal/ttgov2.h
index e622af02..0df3146e 100644
--- a/src/hal/ttgov2.h
+++ b/src/hal/ttgov2.h
@@ -25,8 +25,8 @@
 
 // Hardware pin definitions for TTGO V2 Board with OLED SSD1306 0,96" I2C Display
 #define OLED_RST U8X8_PIN_NONE // connected to CPU RST/EN
-#define OLED_SDA GPIO_NUM_21  // ESP32 GPIO21 -- SD1306 D1+D2
-#define OLED_SCL GPIO_NUM_22 // ESP32 GPIO22 -- SD1306 D0
+#define I2C_SDA GPIO_NUM_21  // ESP32 GPIO21 -- SD1306 D1+D2
+#define I2C_SCL GPIO_NUM_22 // ESP32 GPIO22 -- SD1306 D0
 
 /* source:
 https://www.thethingsnetwork.org/forum/t/big-esp32-sx127x-topic-part-2/11973
diff --git a/src/hal/ttgov21new.h b/src/hal/ttgov21new.h
index ce64323f..5cadc961 100644
--- a/src/hal/ttgov21new.h
+++ b/src/hal/ttgov21new.h
@@ -26,5 +26,5 @@
 
 // Hardware pin definitions for TTGO V2 Board with OLED SSD1306 0,96" I2C Display
 #define OLED_RST U8X8_PIN_NONE // connected to CPU RST/EN
-#define OLED_SDA GPIO_NUM_21 // ESP32 GPIO21 -- SD1306 D1+D2
-#define OLED_SCL GPIO_NUM_22 // ESP32 GPIO22 -- SD1306 D0
\ No newline at end of file
+#define I2C_SDA GPIO_NUM_21 // ESP32 GPIO21 -- SD1306 D1+D2
+#define I2C_SCL GPIO_NUM_22 // ESP32 GPIO22 -- SD1306 D0
\ No newline at end of file
diff --git a/src/hal/ttgov21old.h b/src/hal/ttgov21old.h
index f6882187..c423ca67 100644
--- a/src/hal/ttgov21old.h
+++ b/src/hal/ttgov21old.h
@@ -28,5 +28,5 @@
 
 // Hardware pin definitions for TTGO V2 Board with OLED SSD1306 0,96" I2C Display
 #define OLED_RST U8X8_PIN_NONE // connected to CPU RST/EN
-#define OLED_SDA GPIO_NUM_21 // ESP32 GPIO21 -- SD1306 D1+D2
-#define OLED_SCL GPIO_NUM_22 // ESP32 GPIO22 -- SD1306 D0
+#define I2C_SDA GPIO_NUM_21 // ESP32 GPIO21 -- SD1306 D1+D2
+#define I2C_SCL GPIO_NUM_22 // ESP32 GPIO22 -- SD1306 D0
diff --git a/src/lorawan.cpp b/src/lorawan.cpp
index 0ee8b6c0..5ffed2cb 100644
--- a/src/lorawan.cpp
+++ b/src/lorawan.cpp
@@ -37,6 +37,27 @@ void gen_lora_deveui(uint8_t *pdeveui) {
   }
 }
 
+/* The above function should be changed to this one, but this would be a breaking change
+
+// DevEUI generator using devices's MAC address
+void gen_lora_deveui(uint8_t *pdeveui) {
+  uint8_t *p = pdeveui, dmac[6];
+  ESP_ERROR_CHECK(esp_efuse_mac_get_default(dmac));
+   // deveui is LSB, we reverse it so TTN DEVEUI display
+  // will remain the same as MAC address
+  // MAC is 6 bytes, devEUI 8, set middle 2 ones
+  // to an arbitrary value
+  *p++ = dmac[5];
+  *p++ = dmac[4];
+  *p++ = dmac[3];
+  *p++ = 0xff;
+  *p++ = 0xfe;
+  *p++ = dmac[2];
+  *p++ = dmac[1];
+  *p++ = dmac[0];
+}
+*/
+
 // Function to do a byte swap in a byte array
 void RevBytes(unsigned char *b, size_t c) {
   u1_t i;
@@ -79,7 +100,7 @@ void get_hard_deveui(uint8_t *pdeveui) {
 #ifdef MCP_24AA02E64_I2C_ADDRESS
   uint8_t i2c_ret;
   // Init this just in case, no more to 100KHz
-  Wire.begin(OLED_SDA, OLED_SCL, 100000);
+  Wire.begin(I2C_SDA, I2C_SCL, 100000);
   Wire.beginTransmission(MCP_24AA02E64_I2C_ADDRESS);
   Wire.write(MCP_24AA02E64_MAC_ADDRESS);
   i2c_ret = Wire.endTransmission();