diff --git a/src/i2c.c b/src/i2c.c
index 8e8e56e..ab4356c 100644
--- a/src/i2c.c
+++ b/src/i2c.c
@@ -24,6 +24,8 @@ int i2c_open(const struct i2c_bb *i2c)
 
     res = gpio_open(i2c->sda);
     res |= gpio_open(i2c->scl);
+    res |= gpio_write(i2c->sda, 1);
+    res |= gpio_write(i2c->scl, 1);
 
     return res;
 }
@@ -51,7 +53,7 @@ int i2c_read(const struct i2c_bb *i2c, uint8_t slave_addr, char *buffer, unsigne
     }
 
     start_condition(i2c);
-    write_byte(i2c, (slave_addr & 0x80));
+    write_byte(i2c, (slave_addr << 1) | 1);
     for(i = 0; i < len; i++) {
         buffer[i] = read_byte(i2c, true);
     }
@@ -72,7 +74,7 @@ int i2c_write(const struct i2c_bb *i2c, uint8_t slave_addr, const char *buffer,
     }
 
     start_condition(i2c);
-    write_byte(i2c, (slave_addr & 0x7F));
+    write_byte(i2c, slave_addr << 1);
     for(i = 0; i < len; i++) {
         write_byte(i2c, buffer[i]);
     }
@@ -136,7 +138,7 @@ static uint8_t read_byte(const struct i2c_bb *i2c, bool ack)
     if(ack) {
         write_bit(i2c, 0);
     } else {
-        write_bit(i2c, 0);
+        write_bit(i2c, 1);
     }
 
     return res;
@@ -146,15 +148,15 @@ static void write_bit(const struct i2c_bb *i2c, uint8_t bit)
 {
     assert( NULL != i2c);
 
-    if((bit & 0x01) > 0) {
+    if(bit > 0) {
         gpio_write(i2c->sda, 1);
     } else {
-        gpio_write(i2c->sda, 1);
+        gpio_write(i2c->sda, 0);
     }
     usleep(5);
     gpio_write(i2c->scl, 1);
     usleep(5);
-    gpio_write(i2c->scl, 1);
+    gpio_write(i2c->scl, 0);
 }
 
 static uint8_t read_bit(const struct i2c_bb *i2c)
@@ -168,7 +170,7 @@ static uint8_t read_bit(const struct i2c_bb *i2c)
     gpio_write(i2c->scl, 1);
     usleep(5);
     gpio_read(i2c->sda, &res);
-    gpio_write(i2c->scl, 1);
+    gpio_write(i2c->scl, 0);
 
     return (uint8_t) res;
 }