diff --git a/Makefile b/Makefile
index 40904bf..5820e74 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@
 PROGRAMMER_ARGS = 
 
 MAIN = avrrfm.c
-SRC = rfm69.c spi.c usart.c
+SRC = rfm69.c i2c.c spi.c usart.c
 
 CC = avr-gcc
 OBJCOPY = avr-objcopy
@@ -33,7 +33,7 @@
 OBJ = $(SRC:.c=.o) 
 OBJ = $(SRC:.S=.o)
 	
-$(TARGET).elf: pins.h rfm69.h spi.h usart.h utils.h Makefile
+$(TARGET).elf: pins.h rfm69.h i2c.h spi.h usart.h utils.h Makefile
 
 all: $(TARGET).hex
 
diff --git a/avrrfm.c b/avrrfm.c
index 0716777..5ba9d4f 100644
--- a/avrrfm.c
+++ b/avrrfm.c
@@ -39,8 +39,8 @@
     PORT_SPI |= (1 << PIN_MISO);
 
     // set SDA and SCL as output pin
-    // DDR_I2C |= (1 << PIN_SCL);
-    // DDR_I2C |= (1 << PIN_SDA);
+    DDR_I2C |= (1 << PIN_SCL);
+    DDR_I2C |= (1 << PIN_SDA);
 
     // set radio CS and RST pin as output pin
     DDR_RFM |= (1 << PIN_RCS);
diff --git a/i2c.c b/i2c.c
new file mode 100644
index 0000000..f6d52c1
--- /dev/null
+++ b/i2c.c
@@ -0,0 +1,37 @@
+/* 
+ * File:   i2c.c
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 15. Dezember 2023, 19:01
+ */
+
+#include "i2c.h"
+
+void i2cStart(void) {
+    TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTA);
+    loop_until_bit_is_set(TWCR, TWINT);
+}
+
+void i2cStop(void) {
+    TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);
+}
+
+void i2cSend(uint8_t data) {
+    TWDR = data;
+    TWCR = (1 << TWINT) | (1 << TWEN);
+    loop_until_bit_is_set(TWCR, TWINT);
+}
+
+uint8_t i2cReadAck(void) {
+    TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWEA);
+    loop_until_bit_is_set(TWCR, TWINT);
+
+    return TWDR;
+}
+
+uint8_t i2cReadNack(void) {
+    TWCR = (1 << TWINT) | (1 << TWEN);
+    loop_until_bit_is_set(TWCR, TWINT);
+
+    return TWDR;
+}
\ No newline at end of file
diff --git a/i2c.h b/i2c.h
new file mode 100644
index 0000000..d62f3af
--- /dev/null
+++ b/i2c.h
@@ -0,0 +1,48 @@
+/* 
+ * File:   i2c.h
+ * Author: torsten.roemer@luniks.net
+ *
+ * Created on 15. Dezember 2023, 19:01
+ */
+
+#ifndef I2C_H
+#define I2C_H
+
+#include <avr/io.h>
+#include <util/twi.h> // TODO check status register
+
+#include "pins.h"
+
+/**
+ * Begins a message.
+ */
+void i2cStart(void);
+
+/**
+ * Ends a message.
+ */
+void i2cStop(void);
+
+/**
+ * Transmits the given byte of data.
+ * 
+ * @param data
+ */
+void i2cSend(uint8_t data);
+
+/**
+ * Reads one byte with ack.
+ * 
+ * @return data
+ */
+uint8_t i2cReadAck(void);
+
+/**
+ * Reads one byte without ack.
+ * 
+ * @return 
+ */
+uint8_t i2cReadNack(void);
+
+#endif /* I2C_H */
+
diff --git a/rfm69.c b/rfm69.c
index 70b66f4..669f6e5 100644
--- a/rfm69.c
+++ b/rfm69.c
@@ -98,9 +98,9 @@
     do { } while (!(regRead(OSC1) & 0x40));
     
     // LNA 200 Ohm, gain AGC (default)
-    // regWrite(0x18, 0x88);
+    // regWrite(LNA, 0x88);
     // reduce gain for transmitter and receiver are so close to each other
-    regWrite(LNA, 0x8c);
+    regWrite(LNA, 0x86);
     
     // freq of DC offset canceller and channel filter bandwith (default)
     regWrite(RX_BW, 0x55);
@@ -166,7 +166,7 @@
     spiSel();
     transmit(FIFO);
     for (size_t i = 0; i < len; i++) {
-        payload[i] = (transmit(FIFO));
+        payload[i] = transmit(FIFO);
     }
     spiDes();
     
diff --git a/utils.h b/utils.h
index 3d9a00b..a924c21 100644
--- a/utils.h
+++ b/utils.h
@@ -35,6 +35,5 @@
     _a < _b ? _a : _b;       \
 })
 
-
 #endif /* UTILS_H */