diff --git a/tests/gy521_driver/test_gy521_driver.c b/tests/gy521_driver/test_gy521_driver.c
index 2784f1b..e2f12b5 100644
--- a/tests/gy521_driver/test_gy521_driver.c
+++ b/tests/gy521_driver/test_gy521_driver.c
@@ -6,45 +6,70 @@
 #include <cmocka.h>
 #include "gy521_driver.h"
 
+#define WRITE_BIT   (1<<7)
+
+uint8_t fake_twi_addr = 0x0;
+uint8_t fake_twi_data[16] = {0x0};
 
-/* A test case that does nothing and succeeds. */
-static void null_test_success(void **state) {
-    (void) state; /* unused */
-}
 
 /* Fake Object for TWI_TX*/
 void fake_twi_tx(uint8_t slave_addr, uint8_t *data, uint8_t size)
 {
-
+    fake_twi_addr = slave_addr; 
 }
 
+/* Fake Object for TWI_RX*/
+void fake_twi_rx(uint8_t slave_addr, uint8_t *data, uint8_t size)
+{
+    fake_twi_addr = slave_addr;
+    for(int i = 0; i < size; i++) {
+        *data++ = fake_twi_data[i];
+    }
+}
+
+
+
+/*Setup the fake twi*/
+void (*gy521_twi_tx)(uint8_t, uint8_t*, uint8_t) = &fake_twi_tx;
+void (*gy521_twi_rx)(uint8_t, uint8_t*, uint8_t) = &fake_twi_rx;
+
 /* Tests the donothing function */ 
 static void test_gy521_init(void **state) { 
+    gy521_module *m = gy521_new();
+    assert_false(gy521_init(m, 0x0));
+    assert_false(gy521_init(m, 0x67));
+    assert_false(gy521_init(m, 0x6A));
 
-    _Bool result = init_gy521(0); 
-    assert_false(result);
+    /*Check for it's confirmation of the right twi device*/
+    assert_false(gy521_init(m, TWI_GY521_ADDR1));
 
-    result = init_gy521(1);
-    assert_false(result);
+    /*Now give it the correct response*/
+    fake_twi_data[0] = TWI_GY521_ADDR1;
+    assert_true(gy521_init(m, TWI_GY521_ADDR1));
+    assert_true(TWI_GY521_ADDR1 == fake_twi_addr); 
 
-    result = init_gy521((uint8_t) TWI_GY521_ADDR1);
-    assert_true(result);
+
+    fake_twi_data[0] = TWI_GY521_ADDR2;
+    assert_true(gy521_init(m, TWI_GY521_ADDR2));
+    assert_true(TWI_GY521_ADDR2 == fake_twi_addr); 
+
+    gy521_free(m);
  
 }
 
-static void test_gy521_module_methods(void **state) {
-    gy521_module *module = malloc(sizeof(gy521_module));
-    assert_true(module_test(*module)); 
-}
 
+static void test_gy521_update(void **sate)
+{
+    assert_false(1);
+}
 
 
 int main(void)
 {
     const struct CMUnitTest tests[] = {
-        cmocka_unit_test(null_test_success),
         cmocka_unit_test(test_gy521_init),
-        cmocka_unit_test(test_gy521_module_methods),
+        cmocka_unit_test(test_gy521_update),
+
     }; 
     return cmocka_run_group_tests(tests, NULL, NULL);
 }