Index: firmware/App/Modes/ModeDrain.c
===================================================================
diff -u -rdcbd821e41803adc6e582d909207bc97f85ff939 -r8a553b10a224c745cb4bd6d963c867391905ba8c
--- firmware/App/Modes/ModeDrain.c	(.../ModeDrain.c)	(revision dcbd821e41803adc6e582d909207bc97f85ff939)
+++ firmware/App/Modes/ModeDrain.c	(.../ModeDrain.c)	(revision 8a553b10a224c745cb4bd6d963c867391905ba8c)
@@ -1,65 +1,326 @@
 /**************************************************************************
- *
- *  Copyright (c) 2019-2019 Diality Inc. - All Rights Reserved.
- *
- *  THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
- *  WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
- *
- *  @file ModeDrain.c
- *
- *  @date 20-Dec-2019
- *  @author L. Baloa
- *
- *  @brief Top-level state machine for the drain mode.
- *
- **************************************************************************/
+*
+* Copyright (c) 2019-2021 Diality Inc. - All Rights Reserved.
+*
+* THIS CODE MAY NOT BE COPIED OR REPRODUCED IN ANY FORM, IN PART OR IN
+* WHOLE, WITHOUT THE EXPLICIT PERMISSION OF THE COPYRIGHT OWNER.
+*
+* @file    ModeDrain.c
+*
+* @author  (last)      Sean Nash
+* @date    (last)      12-Nov-2021
+*
+* @author  (original)  Leonardo Baloa
+* @date    (original)  20-Dec-2019
+*
+***************************************************************************/
 
-#include <ModeDrain.h>
-#include "Common.h"
+#include "ConcentratePumps.h"
+#include "ConductivitySensors.h"
+#include "DrainPump.h"
+#include "Heaters.h"
+#include "ModeDrain.h"
 #include "OperationModes.h"
+#include "Pressures.h"
+#include "Reservoirs.h"
+#include "ROPump.h"
+#include "SystemComm.h"
+#include "TaskGeneral.h"
+#include "TemperatureSensors.h"
+#include "Timers.h"
+#include "Valves.h"
 
+/**
+ *  @addtogroup DGDrainMode
+ *  @{
+ */
+
+// ********** private definitions **********
+
+#define TARGET_DRAIN_PUMP_RPM           2300                                                  ///< Target drain pump speed (in RPM).
+#define DRAIN_WEIGHT_UNCHANGE_TIMEOUT   ( 2 * MS_PER_SECOND )                                 ///< Time period of unchanged weight during draining before timeout.
+
+#define DRAIN_EMPTY_TARE_WAIT           ( MS_PER_SECOND / TASK_GENERAL_INTERVAL )             /// Time period to wait after drain complete and before taring load cells.
+
+#define TARGET_RO_PRESSURE_PSI          130                                                   ///< Target pressure for RO pump.
+#define TARGET_RO_FLOW_RATE_L           0.3                                                   ///< Target flow rate for RO pump.
+
+#define DELAY_RES_DRAIN_VALVE_MS        1000                                                  ///< Delay reservoir drain valve open by 1 second.
+#define DELAY_DRAIN_PUMP_MS             2000                                                  ///< Delay drain pump on by 2 seconds.
+
+#define DIALYSATE_DRAIN_TIME_OUT        ( 2 * SEC_PER_MIN * MS_PER_SECOND )                   ///< Dialysate drain time out.
+
+/// Time period to wait for concentrate lines to rinse.
+#define RINSE_CONCENTRATE_LINES_WAIT    ( 25 * MS_PER_SECOND / TASK_GENERAL_INTERVAL )
+/// Reserver the concentrate speed to rinse out concentrate lines.
+#define RINSE_SPEED                     ( ( CONCENTRATE_PUMP_MAX_SPEED - 3.0 ) * -1.0 )
+
 // ********** private data **********
 
+static DG_DRAIN_STATE_T drainState;                                                           ///< Currently active drain state.
+static U32 drainEmptyTareTimerCtr;                                                            ///< Timer counter for delay between drain complete and load cell tare.
+static BOOL rinseConcentrateLines;                                                            ///< Flag indicates to rinse concentrate lines.
+static U32 rinseConcentrateLinesTimerCtr;                                                     ///< Timer counter for rinsing concentrate lines.
+static U32 dialysateDrainStartTime;                                                           ///< Dialysate drain start time.
+
 // ********** private function prototypes **********
+static DG_DRAIN_STATE_T handleDrainStateStart( void );
+static DG_DRAIN_STATE_T handleDrainStateDrain( void );
+static DG_DRAIN_STATE_T handleDrainStateTare( void );
+static DG_DRAIN_STATE_T handleRinseState( void );
 
-/*************************************************************************
- * @brief initDrainMode
- * The initOpParamsMode function initializes the Drain Mode module.
- * @details
- * Inputs : none
- * Outputs : Operating Parameters Mode module initialized.
- * @param none
+/*********************************************************************//**
+ * @brief
+ * The initDrainMode function initializes the drain mode module.
+ * @details Inputs: none
+ * @details Outputs: drainState, drainEmptyTareTimerCtr, dialysateDrainStartTime
  * @return none
  *************************************************************************/
 void initDrainMode( void )
 {
+    drainState              = DG_DRAIN_STATE_START;
+    drainEmptyTareTimerCtr  = 0;
+    rinseConcentrateLines = FALSE;
+    rinseConcentrateLinesTimerCtr = 0;
+    dialysateDrainStartTime = 0;
 }
 
-/*************************************************************************
- * @brief transitionToDrainMode
- * The transitionToDrainMode function prepares for transition to drain \n
- * mode.
- * @details
- * Inputs : none
- * Outputs :
- * @param none
- * @return none
+/*********************************************************************//**
+ * @brief
+ * The transitionToDrainMode function prepares for transition to drain mode.
+ * @details Inputs: none
+ * @details Outputs: Drain mode initialized
+ * @return initial state
  *************************************************************************/
-void transitionToDrainMode( void )
+U32 transitionToDrainMode( void )
 {
+    // re-initialize each time we transition to drain mode
+    initDrainMode();
+
+    DG_RESERVOIR_ID_T inactiveReservoir = getInactiveReservoir();
+
+    if ( DG_RESERVOIR_1 == inactiveReservoir )
+    {
+        setValveStateDelayed( VRD1, VALVE_STATE_OPEN, DELAY_RES_DRAIN_VALVE_MS );
+    }
+    else if ( DG_RESERVOIR_2 == inactiveReservoir )
+    {
+        setValveStateDelayed( VRD2, VALVE_STATE_OPEN, DELAY_RES_DRAIN_VALVE_MS );
+    }
+    // set initial actuator states
+    setValveState( VDR, VALVE_STATE_DRAIN_C_TO_NO );
+    setDrainPumpTargetRPMDelayed( TARGET_DRAIN_PUMP_RPM, DELAY_DRAIN_PUMP_MS );
+
+    // NOTE: The target flow rate should be set prior to setting the start primary heater
+    // because the initial guess in the heaters driver needs the target flow to calculate
+    // the new PWMs for the main and small primary heaters
+#ifndef DISABLE_FLOW_CONTROL_TREATMENT
+    setROPumpTargetFlowRateLPM( TARGET_RO_FLOW_RATE_L, TARGET_RO_PRESSURE_PSI );
+#endif
+    setHeaterTargetTemperature( DG_PRIMARY_HEATER, getPrimaryHeaterTargetTemperature() );
+    startHeater( DG_PRIMARY_HEATER );
+
+    return drainState;
 }
 
-/*************************************************************************
- * @brief execDrainMode
- * The execDrainMode function executes the Drain Mode state machine.
- * @details
- * Inputs : none
- * Outputs :
- * @param none
+/*********************************************************************//**
+ * @brief
+ * The execDrainMode function executes the drain mode state machine.
+ * @details Inputs: drainState
+ * @details Outputs: Check water quality, drain mode state machine executed
+ * @return current state.
+ *************************************************************************/
+U32 execDrainMode( void )
+{
+    // check inlet water conductivity, temperature, pressure, and RO rejection ratio
+    checkInletWaterConductivity();
+    checkInletWaterTemperature();
+    checkInletPressure();
+    checkRORejectionRatio();
+
+    // execute current drain state
+    switch ( drainState )
+    {
+        case DG_DRAIN_STATE_START:
+            drainState = handleDrainStateStart();
+            break;
+
+        case DG_DRAIN_STATE_DRAIN:
+            drainState = handleDrainStateDrain();
+            break;
+
+        case DG_DRAIN_STATE_TARE:
+            drainState = handleDrainStateTare();
+            break;
+
+        case DG_DRAIN_STATE_RINSE:
+            drainState = handleRinseState();
+            break;
+
+        default:
+            SET_ALARM_WITH_2_U32_DATA( ALARM_ID_DG_SOFTWARE_FAULT, SW_FAULT_ID_DRAIN_MODE_INVALID_EXEC_STATE, drainState )
+            drainState = DG_DRAIN_STATE_START;
+            break;
+    }
+
+    return drainState;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The getCurrentDrainState function returns the current state of the drain mode.
+ * @details Inputs: drainState
+ * @details Outputs: none
+ * @return the current state of drain mode.
+ *************************************************************************/
+DG_DRAIN_STATE_T getCurrentDrainState( void )
+{
+    return drainState;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The signalDrainModeRinseConcentrateLines function sets the flag for drain
+ * mode to rinse concentrate lines.
+ * @details Inputs: none
+ * @details Outputs: rinseConcentrateLines
  * @return none
  *************************************************************************/
-void execDrainMode( void )
+void signalDrainModeRinseConcentrateLines( BOOL rinse )
 {
+    rinseConcentrateLines = rinse;
+}
 
+/*********************************************************************//**
+ * @brief
+ * The handleDrainStateStart function handles the drain start state of
+ * the drain mode state machine.
+ * @details Inputs: none
+ * @details Outputs: dialysateDrainStartTime
+ * @return the next state
+ *************************************************************************/
+static DG_DRAIN_STATE_T handleDrainStateStart( void )
+{
+    DG_DRAIN_STATE_T state = DG_DRAIN_STATE_START;
+
+    if ( TRUE == isDrainPumpOn() )
+    {
+        dialysateDrainStartTime = getMSTimerCount();
+        state                   = DG_DRAIN_STATE_DRAIN;
+    }
+
+    return state;
 }
 
+/*********************************************************************//**
+ * @brief
+ * The handleDrainStateDrain function handles the drain state of the drain
+ * mode state machine.
+ * @details Inputs: none
+ * @details Outputs: none
+ * @return the next state
+ *************************************************************************/
+static DG_DRAIN_STATE_T handleDrainStateDrain( void )
+{
+    DG_DRAIN_STATE_T result = DG_DRAIN_STATE_DRAIN;
+    DG_RESERVOIR_ID_T inactiveReservoir = getInactiveReservoir();
+
+    // if we have reached our target drain to volume (by weight) or cannot drain anymore, we are done draining - go back to generation idle mode
+    if ( TRUE == hasTargetDrainVolumeBeenReached( inactiveReservoir, DRAIN_WEIGHT_UNCHANGE_TIMEOUT ) )
+    {
+        signalDrainPumpHardStop();
+
+        if ( DG_RESERVOIR_1 == inactiveReservoir )
+        {
+            setValveState( VRD1, VALVE_STATE_CLOSED );
+        }
+        else if ( DG_RESERVOIR_2 == inactiveReservoir )
+        {
+            setValveState( VRD2, VALVE_STATE_CLOSED );
+        }
+
+        if ( TRUE == isReservoirTarePending() )
+        {   // Tare reservoir load cells at empty if requested
+            result = DG_DRAIN_STATE_TARE;
+        }
+        else
+        {
+            requestNewOperationMode( DG_MODE_GENE );
+        }
+    }
+
+    // Drain timed out raise the alarm
+    if ( TRUE == didTimeout( dialysateDrainStartTime, DIALYSATE_DRAIN_TIME_OUT ) )
+    {
+        activateAlarmNoData( ALARM_ID_DG_DIALYSATE_DRAIN_TIME_OUT );
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The handleDrainStateTare function handles the tare state of the drain mode
+ * state machine.
+ * @details Inputs: drainEmptyTareTimerCtr
+ * @details Outputs: drainEmptyTareTimerCtr
+ * @return the next state
+ *************************************************************************/
+static DG_DRAIN_STATE_T handleDrainStateTare( void )
+{
+    DG_DRAIN_STATE_T result = DG_DRAIN_STATE_TARE;
+    DG_RESERVOIR_ID_T inactiveReservoir = getInactiveReservoir();
+
+    if ( ++drainEmptyTareTimerCtr > DRAIN_EMPTY_TARE_WAIT )
+    {
+        drainEmptyTareTimerCtr = 0;
+        tareLoadCellsAtEmpty( inactiveReservoir );
+
+        setValveState( VRD1, VALVE_STATE_CLOSED );
+        setValveState( VRD2, VALVE_STATE_CLOSED );
+
+        if ( TRUE == rinseConcentrateLines )
+        {
+            setConcentratePumpTargetSpeed( CONCENTRATEPUMPS_CP1_ACID, RINSE_SPEED );
+            setConcentratePumpTargetSpeed( CONCENTRATEPUMPS_CP2_BICARB, RINSE_SPEED );
+            requestConcentratePumpOn( CONCENTRATEPUMPS_CP1_ACID );
+            requestConcentratePumpOn( CONCENTRATEPUMPS_CP2_BICARB );
+        }
+        rinseConcentrateLinesTimerCtr = 0;
+        result = DG_DRAIN_STATE_RINSE;
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
+ * The handleRinseState function handles the tare state of the drain mode
+ * state machine.
+ * @details Inputs: drainEmptyTareTimerCtr
+ * @details Outputs: drainEmptyTareTimerCtr
+ * @return the next state
+ *************************************************************************/
+static DG_DRAIN_STATE_T handleRinseState( void )
+{
+    DG_DRAIN_STATE_T result = DG_DRAIN_STATE_RINSE;
+
+    if ( TRUE == rinseConcentrateLines )
+    {
+        if ( ++rinseConcentrateLinesTimerCtr > RINSE_CONCENTRATE_LINES_WAIT )
+        {
+            rinseConcentrateLinesTimerCtr = 0;
+            requestConcentratePumpOff( CONCENTRATEPUMPS_CP1_ACID );
+            requestConcentratePumpOff( CONCENTRATEPUMPS_CP2_BICARB );
+            requestNewOperationMode( DG_MODE_GENE );
+        }
+    }
+    else
+    {
+        requestNewOperationMode( DG_MODE_GENE );
+    }
+
+    return result;
+}
+
+/**@}*/