diff --git a/inc/pid.h b/inc/pid.h
new file mode 100644
--- /dev/null
+++ b/inc/pid.h
@@ -0,0 +1,16 @@
+#ifndef PIDS_H
+#define PIDS_H
+
+#include "stm32f3xx_hal.h"
+#include "states.h"
+
+typedef struct {
+	int16_t last_pid_temp;
+	uint8_t last_pid_temp_frac;
+	int32_t i_state;
+} pid_state_t;
+
+void pid_init(pid_state_t* state);
+int16_t pid_update(therm_settings_t* set, therm_status_t* status, pid_state_t* state);
+
+#endif