tested ELM327 connection and refactored bt driver to include elm327

due_obd2/obd2_elm327.cpp

@@ -0,0 +1,62 @@
+#include <string.h>
+#include "ELMduino.h"
+
+#include "obd2_elm327.h"
+
+ELM327 myELM327;
+
+void obd2_elm327_init(obd2_elm327_t *elm327)
+{
+    elm327->bt_state = BT_INITIALISING;
+}
+
+void obd2_elm327_get_state(obd2_elm327_t *elm327, char *state)
+{
+    // char bt_states[3][13] = {"Initializing", "Connecting  ", "Connected   "};
+    // char bt_states;
+    // (void) bt_states;
+
+    if (sizeof(state) != BT_STATE_LENGTH)
+    {
+        /* result string must be of size 13 */
+        return;
+    }
+    switch (elm327->bt_state)
+    {
+    case BT_INITIALISING:
+        strcpy(state, "Initializing");
+        break;
+    case BT_CONNECTING:
+        strcpy(state, "Connecting  ");
+        break;
+    case BT_CONNECTED:
+        strcpy(state, "Connected   ");
+        break;
+    default:
+        strcpy(state, "Unknown     ");
+        break;
+    }
+}
+
+void obd2_elm327_process(obd2_elm327_t *elm327)
+{
+    if (elm327->bt_state != BT_CONNECTED)
+    {
+        __UINT32_TYPE__ bt_state = digitalRead(BT_STATE_PIN);
+
+        if (bt_state != elm327->bt_state)
+        {
+            if (bt_state)
+            {
+                elm327->bt_state = BT_CONNECTED;
+            }
+            else
+            {
+                elm327->bt_state = BT_INITIALISING;
+            }
+            elm327->on_state_change();
+        }
+    }
+
+    /* TODO read from Serial2 to read OBD2 data */
+}