diff --git a/src/pid.c b/src/pid.c
--- a/src/pid.c
+++ b/src/pid.c
@@ -3,23 +3,64 @@
 //
 
 #include "pid.h"
+#include "flash.h"
 
 // PID implementation
 
-void pid_init(pid_state_t* state)
+static pid_state_t state;
+
+
+void pid_init()
 {
-	state->i_state = 0;
-	state->last_pid_temp = 0;
-	state->last_pid_temp_frac = 0;
+	state.i_state = 0;
+	state.last_pid_temp = 0;
+	state.last_pid_temp_frac = 0;
 }
 
-int16_t pid_update(therm_settings_t* set, therm_status_t* status, pid_state_t *state)
+float pid_process(void)
 {
 
+//            #ifdef MAX31865_RTD_SENSOR
+//            max31865_readtemp(spi_get(), &set, &status);
+//			#else
+//			max31855_readtemp(spi_get(), &set, &status); // Read MAX31855
+//			#endif
+
+		float ssr_output = 0;
+
+
+		if(runtime_status()->pid_enabled)
+		{
+			// Get ssr output for next time
+			int16_t power_percent = pid_update();
+
+			if(flash_getsettings()->val.plant_type == PLANT_HEATER)
+				power_percent *= -1;
+
+			//power-percent is 0-1000?
+			ssr_output = power_percent; //(((uint32_t)SSR_PERIOD * (uint32_t)10 * (uint32_t)100) * power_percent) / (uint32_t)1000000;
+
+			// put ssr output on display
+			ssd1306_drawstring("      ", 0, 90); //fixme: this is bad, but I can't get the old digits to clear otherwise
+			char tempstr[6];
+			itoa(ssr_output, tempstr, 10);
+			ssd1306_drawstring(tempstr, 0, 90);
+		}
+		else
+		{
+			ssr_output = 0.0;
+		}
+
+		return ssr_output;
+}
+
+int16_t pid_update(void)
+{
+	therm_status_t* status = runtime_status();
+	therm_settings_t* set = flash_getsettings();
+
   // Convert temperature to fixed point number with 1/10th resolution
-  int8_t temp_frac = status->temp_frac > 9 ? status->temp_frac / 10 : status->temp_frac;
-  temp_frac = status->temp > 0 ? temp_frac : temp_frac * -1;
-  int32_t temp = (status->temp * 10) + temp_frac;
+  float temp = status->temp;
 
   // Calculate instantaneous error
   int16_t error = status->setpoint * 10 - temp; // TODO: Use fixed point fraction
@@ -28,7 +69,7 @@ int16_t pid_update(therm_settings_t* set
   int32_t p_term = set->val.k_p * error;
 
   // Error accumulator (integrator)
-  state->i_state += error;
+  state.i_state += error;
 
   // to prevent the iTerm getting huge from lots of 
   //  error, we use a "windup guard" 
@@ -39,18 +80,18 @@ int16_t pid_update(therm_settings_t* set
   int32_t windup_guard_res = (set->val.windup_guard * 10) / set->val.k_i;
 
   // Calculate integral term with windup guard 
-  if (state->i_state > windup_guard_res)
-	  state->i_state = windup_guard_res;
-  else if (state->i_state < -windup_guard_res)
-	  state->i_state = -windup_guard_res;
+  if (state.i_state > windup_guard_res)
+	  state.i_state = windup_guard_res;
+  else if (state.i_state < -windup_guard_res)
+	  state.i_state = -windup_guard_res;
 
-  int32_t i_term = set->val.k_i * state->i_state;
+  int32_t i_term = set->val.k_i * state.i_state;
 
   // Calculate differential term (slope since last iteration)
-  int32_t d_term = (set->val.k_d * (temp - state->last_pid_temp));
+  int32_t d_term = (set->val.k_d * (temp - state.last_pid_temp));
 
   // Save temperature for next iteration
-  state->last_pid_temp = temp;
+  state.last_pid_temp = temp;
 
   int16_t result = (p_term + i_term - d_term) / 10;