+static uint8_t cmd_buffer[15];
+static uint8_t cmd_length = 0;
+static uint8_t cmd_read_pos = 0;
+static uint16_t baud_rate = 9600;
+static uint16_t baud_change = 0;
+static uint32_t baud_changed_at = 0;
+
+static uint8_t dispatch_command(const uint8_t *, uint8_t);
+uint8_t interface_command(const uint8_t *, uint8_t);