diff --git a/.vscode/settings.json b/.vscode/settings.json
index 527a059..3400d72 100755
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,6 +1,8 @@
 {
     "files.associations": {
         "neopixel_driver.h": "c",
-        "bit_bang_neopixel.h": "c"
-    }
+        "bit_bang_neopixel.h": "c",
+        "i2c_slave.h": "c"
+    },
+    "idf.portWin": "COM9"
 }
\ No newline at end of file
diff --git a/src/i2c_slave.c b/src/i2c_slave.c
index dff3d5e..6e22ac2 100644
--- a/src/i2c_slave.c
+++ b/src/i2c_slave.c
@@ -1,2 +1,82 @@
 #include "i2c_slave.h"
+#include "uart_driver.h"
+
+// https://pallavaggarwal.in/2023/10/05/ch32v003-programming-i2c-eeprom/
+void i2c_init() {
+    GPIO_InitTypeDef GPIO_InitStructure={0};
+    I2C_InitTypeDef I2C_InitTSturcture={0};
+
+    RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOC | RCC_APB2Periph_AFIO, ENABLE );
+    RCC_APB1PeriphClockCmd( RCC_APB1Periph_I2C1, ENABLE );
+
+    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
+    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
+    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
+    GPIO_Init( GPIOC, &GPIO_InitStructure );
+
+    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
+    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
+    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
+    GPIO_Init( GPIOC, &GPIO_InitStructure );
+
+    I2C_InitTSturcture.I2C_ClockSpeed = 100*1000;
+    I2C_InitTSturcture.I2C_Mode = I2C_Mode_I2C;
+    I2C_InitTSturcture.I2C_DutyCycle = I2C_DutyCycle_2;
+    I2C_InitTSturcture.I2C_OwnAddress1 = I2C_SLAVE_ADDR;
+    I2C_InitTSturcture.I2C_Ack = I2C_Ack_Enable;
+    I2C_InitTSturcture.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
+
+    NVIC_EnableIRQ(I2C1_EV_IRQn); // Event interrupt
+    NVIC_SetPriority(I2C1_EV_IRQn, 2 << 4);
+    NVIC_EnableIRQ(I2C1_ER_IRQn); // Error interrupt
+    NVIC_SetPriority(I2C1_ER_IRQn, 2 << 4);
+
+    I2C_Init( I2C1, &I2C_InitTSturcture );
+
+    I2C_Cmd( I2C1, ENABLE );
+
+    I2C_AcknowledgeConfig( I2C1, ENABLE );
+}
+
+void I2C1_EV_IRQHandler(void) {
+    uint16_t STAR1, STAR2 __attribute__((unused));
+    STAR1 = I2C1->STAR1;
+    STAR2 = I2C1->STAR2;
+
+    if (STAR1 & I2C_STAR1_ADDR) { // Start event
+        UartStringSend("Start Event\r\n");
+    }
+
+    if (STAR1 & I2C_STAR1_RXNE) { // Write event
+        UartStringSend("Write Event\r\n");
+    }
+
+    if (STAR1 & I2C_STAR1_TXE) { // Read event
+        UartStringSend("Read Event\r\n");
+    }
+
+    if (STAR1 & I2C_STAR1_STOPF) { // Stop event
+        I2C1->CTLR1 &= ~(I2C_CTLR1_STOP); // Clear stop
+        UartStringSend("Stop Event\r\n");
+    }
+}
+
+void I2C1_ER_IRQHandler(void) {
+    uint16_t STAR1 = I2C1->STAR1;
+
+    if (STAR1 & I2C_STAR1_BERR) { // Bus error
+        I2C1->STAR1 &= ~(I2C_STAR1_BERR); // Clear error
+        UartStringSend("Bus error\r\n");
+    }
+
+    if (STAR1 & I2C_STAR1_ARLO) { // Arbitration lost error
+        I2C1->STAR1 &= ~(I2C_STAR1_ARLO); // Clear error
+        UartStringSend("Arbitration lost error\r\n");
+    }
+
+    if (STAR1 & I2C_STAR1_AF) { // Acknowledge failure
+        I2C1->STAR1 &= ~(I2C_STAR1_AF); // Clear error
+        UartStringSend("Ack Failure\r\n");
+    }
+}
 
diff --git a/src/i2c_slave.h b/src/i2c_slave.h
index 09bdb8e..2108757 100644
--- a/src/i2c_slave.h
+++ b/src/i2c_slave.h
@@ -3,6 +3,11 @@
 
 #include <ch32v00x.h>
 
+#define I2C_SLAVE_ADDR 0x33
 
+void i2c_init();
+
+void I2C1_EV_IRQHandler(void) __attribute__((interrupt));
+void I2C1_ER_IRQHandler(void) __attribute__((interrupt));
 
 #endif /* I2C_SLAVE_H */
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
index e46b2da..7f8e055 100755
--- a/src/main.c
+++ b/src/main.c
@@ -4,6 +4,7 @@
 // #include "bit_bang_neopixel.h"
 #include "uart_driver.h"
 #include "hall_driver.h"
+#include "i2c_slave.h"
  
 void NMI_Handler(void) __attribute__((interrupt("WCH-Interrupt-fast")));
 void HardFault_Handler(void) __attribute__((interrupt("WCH-Interrupt-fast")));
@@ -21,11 +22,13 @@ int main(void)
     Delay_Ms(1000);
 
     USARTx_CFG();
-    // UartStringSend("Hello World!\r\n");
+    UartStringSend("Hello World!\r\n");
 
     SPINeoPixelDriverInit();
     // BBNeoPixelDriverInit();
 
+    i2c_init();
+
     init_button();
     ADCConfig();
 
@@ -57,8 +60,8 @@ int main(void)
         adcFlag = 0;
         
         char buffer[64] = {0};
-        sprintf(buffer, "%d\t%d\t%d\t%d\r\n", adc_readings[0], adc_readings[1], adc_readings[2], adc_readings[3]);
-        UartStringSend(buffer);
+        // sprintf(buffer, "%d\t%d\t%d\t%d\r\n", adc_readings[0], adc_readings[1], adc_readings[2], adc_readings[3]);
+        // UartStringSend(buffer);
 
         for (int i = 0; i < 4; i++) {
             if (adc_readings[i] > adc_calibration_values[i] + 5) {
diff --git a/src/uart_driver.c b/src/uart_driver.c
index a1d5c75..331d839 100644
--- a/src/uart_driver.c
+++ b/src/uart_driver.c
@@ -17,7 +17,7 @@ void USARTx_CFG(void) {
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
     GPIO_Init(GPIOD, &GPIO_InitStructure);
 
-    USART_InitStructure.USART_BaudRate = 9600;
+    USART_InitStructure.USART_BaudRate = 115200;
     USART_InitStructure.USART_WordLength = USART_WordLength_8b;
     USART_InitStructure.USART_StopBits = USART_StopBits_1;
     USART_InitStructure.USART_Parity = USART_Parity_No;