diff --git a/pid/controller.cpp b/pid/controller.cpp
new file mode 100644
index 0000000..a5360fe
--- /dev/null
+++ b/pid/controller.cpp
@@ -0,0 +1,48 @@
+/**
+ * Copyright 2017 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <algorithm>
+#include <chrono>
+#include <iostream>
+#include <map>
+#include <memory>
+#include <thread>
+#include <vector>
+
+#include "controller.hpp"
+#include "ec/pid.hpp"
+
+
+void PIDController::pid_process(void)
+{
+    float input;
+    float setpt;
+    float output;
+
+    // Get setpt value
+    setpt = setpt_proc();
+
+    // Get input value
+    input = input_proc();
+
+    // Calculate new output
+    output = ec::pid(get_pid_info(), input, setpt);
+
+    // Output new value
+    output_proc(output);
+
+    return;
+}