diff --git a/firmware/user/src/i2c.c b/firmware/user/src/i2c.c
index 68eb6d8..d00b5cf 100644
--- a/firmware/user/src/i2c.c
+++ b/firmware/user/src/i2c.c
@@ -18,7 +18,7 @@
 #define I2C_TIMEOUT             0xefff
 #define I2C_TIMEOUT_ACK_POLL    0x180
 
-static uint16_t timeout;
+static uint32_t timeout;
 
 
 void i2c_init()
@@ -29,8 +29,7 @@ void i2c_init()
 
     i2c.I2C_ClockSpeed = 666666;
     i2c.I2C_Mode = I2C_Mode_I2C;
-    i2c.I2C_DutyCycle = I2C_DutyCycle_16_9;
-    i2c.I2C_OwnAddress1 = 0x7f;
+    i2c.I2C_DutyCycle = I2C_DutyCycle_2; // 16_9;
     i2c.I2C_Ack = I2C_Ack_Enable;
     i2c.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
     I2C_Init(I2C1, &i2c);
@@ -57,11 +56,13 @@ int8_t i2c_read_addr1b(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len)
     while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED) && timeout--);
     if (!timeout) return -3;
 
+    I2C_AcknowledgeConfig(I2C1, DISABLE);
     I2C_SendData(I2C1, reg);
     timeout = I2C_TIMEOUT;
     while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED) && timeout--);
     if (!timeout) return -4;
 
+    I2C_AcknowledgeConfig(I2C1, ENABLE);
     I2C_GenerateSTART(I2C1, ENABLE);
     timeout = I2C_TIMEOUT;
     while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT) && timeout--);
@@ -79,12 +80,10 @@ int8_t i2c_read_addr1b(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len)
 
        *data++ = I2C_ReceiveData(I2C1);
        len--;
-
-       if (!len) {
-           I2C_GenerateSTOP(I2C1, ENABLE);
-       }
     }
 
+    I2C_GenerateSTOP(I2C1, ENABLE);
+
     return 0;
 }
 
@@ -102,6 +101,8 @@ int8_t i2c_write_addr1b(uint8_t addr, uint8_t reg, const uint8_t *data, uint8_t
     while((I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY) != RESET) && timeout--);
     if (!timeout) return -1;
 
+    I2C_AcknowledgeConfig(I2C1, ENABLE);
+
     I2C_GenerateSTART(I2C1, ENABLE);
     timeout = I2C_TIMEOUT;
     while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT) && timeout--);
@@ -124,11 +125,10 @@ int8_t i2c_write_addr1b(uint8_t addr, uint8_t reg, const uint8_t *data, uint8_t
             I2C_SendData(I2C1, *data++);
             len--;
             while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED));
+            continue;
         }
-        // failed to acknowledge... reset bus
+        // failed to acknowledge...
         if (I2C_GetFlagStatus(I2C1, I2C_FLAG_AF)) {
-            I2C1->STAR1 = 0;
-            I2C_GenerateSTOP(I2C1, ENABLE);
             break;
         }
     }
@@ -138,14 +138,20 @@ int8_t i2c_write_addr1b(uint8_t addr, uint8_t reg, const uint8_t *data, uint8_t
     return 0;
 }
 
-void i2c_write_reg_8b(uint8_t addr, uint8_t reg, uint8_t dat)
+void i2c_write_reg_8b(uint8_t addr, uint8_t reg, const uint8_t dat)
 {
     i2c_write_addr1b(addr, reg, &dat, 1);
 }
 
-int8_t i2c_ack_poll(uint8_t addr)
+int8_t i2c_addr_scan(uint8_t addr)
 {
-    int8_t addr_match = 0;
+    uint8_t found = 1;
+    uint32_t event;
+
+    // no low addresses
+    if ((addr >> 4) == 0) return 0;
+    // no high addresses
+    if ((addr & 0xf8) == 0xf8) return 0;
 
     timeout = I2C_TIMEOUT;
     while((I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY) != RESET) && timeout--);
@@ -156,14 +162,30 @@ int8_t i2c_ack_poll(uint8_t addr)
     while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT) && timeout--);
     if (!timeout) return -2;
 
-    I2C_Send7bitAddress(I2C1, addr, I2C_Direction_Receiver);
+    I2C_Send7bitAddress(I2C1, (addr & 0xfe), (addr & 0x01));
     timeout = I2C_TIMEOUT_ACK_POLL;
-    while (!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED) && timeout--);
-    if (!timeout) {
-        addr_match = -128;
+    if (addr & 1) event = I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED;
+    else          event = I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED;
+
+    while ((I2C_CheckEvent(I2C1, event) == NoREADY) && timeout--) {
+        if (I2C_GetFlagStatus(I2C1, I2C_FLAG_AF)) {
+            found = 0;
+            break;
+        }
     }
 
+    if (!timeout) {
+        found = 0;
+    }
+
+    // send a stop to make sure anything listening knows to stfu
     I2C_GenerateSTOP(I2C1, ENABLE);
 
-    return addr_match;
+    // reset flags; it might be in a fucked state
+    if (!found) {
+        I2C1->STAR1 = 0;
+        return 0;
+    }
+
+    return addr;
 }
diff --git a/firmware/user/src/i2c.h b/firmware/user/src/i2c.h
index a17fe48..7ca772c 100644
--- a/firmware/user/src/i2c.h
+++ b/firmware/user/src/i2c.h
@@ -1,8 +1,5 @@
 /*
- * i2c.h
- *
- *  Created on: Jul 27, 2024
- *      Author: true
+ * Created on: Jul 27, 2024
  */
 
 #ifndef USER_SRC_I2C_H_
@@ -20,9 +17,9 @@ int8_t i2c_read_addr1b(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len);
 int8_t i2c_write_addr1b(uint8_t addr, uint8_t reg, const uint8_t *data, uint8_t len);
 
 uint8_t i2c_read_reg_8b(uint8_t addr, uint8_t reg);
-void i2c_write_reg_8b(uint8_t addr, uint8_t reg, uint8_t dat);
+void i2c_write_reg_8b(uint8_t addr, uint8_t reg, const uint8_t dat);
 
-int8_t i2c_ack_poll(uint8_t devaddr);
+int8_t i2c_addr_scan(uint8_t addr);