Jeisson David Torrecilla A
Created February 7, 2017

Controlled environment (PID pseudocode) Using MATLAB

Here I will show how you can get data from any plant to create a focused controller, in this case i controlled temperature. (Pseudocode PID)

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Controlled environment  (PID pseudocode) Using MATLAB

Things used in this project

Story

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Schematics

Power Circuit

This power circuit was used to activate the actuator necessary to control

PSoC esquematic ON/OFF

PID Esquematic PSoC

Code

ON/OFF Program

C/C++
This is to generate a square signal
#include <project.h>
#include <stdio.h>

#define ADC_CHANNEL_VREF			(0u)
#define ADC_CHANNEL_VTH				(1u)
#define LED_ON						(0u)
#define LED_OFF						(1u)
#define TEMPERATURE_THRESHOLD_HIGH	(2700)
#define TEMPERATURE_THRESHOLD_LOW	(2500)
#define FILTER_COEFFICIENT_TEMPERATURE	(32u)
/* EzI2C Read/Write Boundary */
#define READ_WRITE_BOUNDARY         (0u)

/* Structure that holds the temperature sensor (thermistor) data                 */
/* Use __attribute__((packed)) for GCC and MDK compilers to pack structures      */
/* For other compilers use the corresponding directive.                          */
/* For example, for IAR use the following directive                              */
/* typedef __packed struct {..}struct_name;                                      */
typedef struct __attribute__((packed))
{
	int16 Vth;					/* Voltage across thermistor */
	uint16 Rth;					/* Thermistor resistance */
	int16 temperature;			/* Measured temperature */
}temperature_sensor_data;

/* Function Prototypes */
void InitResources(void);

/* Declare the i2cBuffer to exchange sensor data between Bridge Control 
Panel (BCP) and PSoC Analog Coprocessor */
temperature_sensor_data i2cBuffer = {0, 0, 0};

/*******************************************************************************
* Function Name: main
********************************************************************************
*
* Summary:
*  This function initializes all the resources, and in an infinite loop, measures the temperature from the sensor 
*  readings and to send the data over I2C.
*
* Parameters:
*  None
*
* Return:
*  int
*
* Side Effects:
*   None
*******************************************************************************/
int main()
{
    char stringBuffer[32u];
    /* Variables to hold the the ADC readings */
    int16 adcResultVREF, adcResultVTH;
    int n1=1;
    /* Filter input and output variables for Vref and Vth measurements */
    int16 filterOutputVref=0;
    int16 filterOutputVth=0;
    
    /* Variables to hold calculated resistance and temperature */
    int16 thermistorResistance, temperature;
    
    /* Variable to store the status returned by CyEnterCriticalSection()*/
    uint8 interruptState = 0;
    
    /* Enable global interrupts */
    CyGlobalIntEnable;
    
    /* Initialize hardware resources */
    InitResources();

    /* Infinite Loop */
    for(;;)
    {
        /* Check if the ADC data is ready */
        if(ADC_IsEndConversion(ADC_RETURN_STATUS))
        {
            /* Read the ADC result for reference and thermistor voltages */
            adcResultVREF = ADC_GetResult16(ADC_CHANNEL_VREF);
            adcResultVTH = ADC_GetResult16(ADC_CHANNEL_VTH);
            
            /* Low pass filter the measured ADC counts of Vref */            
            filterOutputVref = (adcResultVREF + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVref) / FILTER_COEFFICIENT_TEMPERATURE;
                    
            /* Low pass filter the measured ADC counts of Vth */         
            filterOutputVth = (adcResultVTH + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVth) / FILTER_COEFFICIENT_TEMPERATURE;
                        
            /* Calculate thermistor resistance */
            thermistorResistance = Thermistor_GetResistance(filterOutputVref, filterOutputVth);           
            
            /* Calculate temperature in degree Celsius using the Component API */
            temperature = Thermistor_GetTemperature(thermistorResistance);
            
            /* Turn ON Ligth and turn OFF fan */ 
            
            while (n1==1){
             Fan_Write(0);
             Ligth_Write(1);
        uint16_t Temp1 = temperature;
        sprintf(stringBuffer, "%d",Temp1);
        UART_UartPutString(stringBuffer);        
        CyDelay(20);
        adcResultVREF = ADC_GetResult16(ADC_CHANNEL_VREF);
            adcResultVTH = ADC_GetResult16(ADC_CHANNEL_VTH);
            
            /* Low pass filter the measured ADC counts of Vref */            
            filterOutputVref = (adcResultVREF + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVref) / FILTER_COEFFICIENT_TEMPERATURE;
                    
            /* Low pass filter the measured ADC counts of Vth */         
            filterOutputVth = (adcResultVTH + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVth) / FILTER_COEFFICIENT_TEMPERATURE;
                        
            /* Calculate thermistor resistance */
            thermistorResistance = Thermistor_GetResistance(filterOutputVref, filterOutputVth);           
            
            /* Calculate temperature in degree Celsius using the Component API */
            temperature = Thermistor_GetTemperature(thermistorResistance);

             if(temperature>2549){
             n1=2;
            } 
            }
            while (n1==2){
             Fan_Write(1);
             Ligth_Write(0);
        uint16_t Temp1 = temperature;
        sprintf(stringBuffer, "%d",Temp1);
        UART_UartPutString(stringBuffer);        
        CyDelay(20);
        adcResultVREF = ADC_GetResult16(ADC_CHANNEL_VREF);
            adcResultVTH = ADC_GetResult16(ADC_CHANNEL_VTH);
            
            /* Low pass filter the measured ADC counts of Vref */            
            filterOutputVref = (adcResultVREF + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVref) / FILTER_COEFFICIENT_TEMPERATURE;
                    
            /* Low pass filter the measured ADC counts of Vth */         
            filterOutputVth = (adcResultVTH + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVth) / FILTER_COEFFICIENT_TEMPERATURE;
                        
            /* Calculate thermistor resistance */
            thermistorResistance = Thermistor_GetResistance(filterOutputVref, filterOutputVth);           
            
            /* Calculate temperature in degree Celsius using the Component API */
            temperature = Thermistor_GetTemperature(thermistorResistance);

             if(temperature<2501){
             n1=1;
            } 
            }
            /* Turn ON Ligth and turn OFF fan*/
            
            
            
            
                   
			/* Enter critical section to check if I2C bus is busy or not */
            interruptState = CyEnterCriticalSection();
            
        	if(!(EZI2C_EzI2CGetActivity() & EZI2C_EZI2C_STATUS_BUSY))
        	{
                /* Update I2C Buffer */
                i2cBuffer.Rth = thermistorResistance;
                i2cBuffer.temperature = temperature;
                i2cBuffer.Vth = filterOutputVth;
            }
			
			/* Exit critical section */
            CyExitCriticalSection(interruptState);
        }
    }
}

/*******************************************************************************
* Function Name: void InitResources(void)
********************************************************************************
*
* Summary:
*  This function initializes all the hardware resources
*
* Parameters:
*  None
*
* Return:
*  None
*
* Side Effects:
*   None
*******************************************************************************/
void InitResources(void)
{
    /* Start EZI2C Slave Component and initialize buffer */
    EZI2C_Start();
    EZI2C_EzI2CSetBuffer1(sizeof(i2cBuffer), READ_WRITE_BOUNDARY, (uint8 *)&i2cBuffer);
        
    /* Start the Scanning SAR ADC Component and start conversion */
    ADC_Start();
    ADC_StartConvert();
    UART_Start();
    /* Start Reference buffer */
    VrefBuffer_Start();
    
    /* Start Programmable Voltage Reference */
    PVref_Start();
    
    /* Enable Programmable Voltage Reference */
    PVref_Enable();
}

/* [] END OF FILE */

MATLAB Code

MATLAB
This is to get data from PSoC
Thanks PSoC Latinoamérica
serial_PSoC=serial('COM4','BaudRate',9600,'Parity','none','DataBits',8,'StopBits',1); %declaración de los parámetros de puerto serial
set(serial_PSoC,'InputBufferSize',4); %número de datos que se van a recibir en este caso yo estoy recibiendo por ejemplo 12.65
fopen(serial_PSoC); 
contador=1; %inicializar un contador que se usa para llenar las posiciones de un vector donde se almacena cada dato recibido por el puerto serial
figure('Name','Conrolador ON/OFF Para generar la señal cuadrada de reconocimiento')        %Iniciar la ventana donde estará la gráfica 
title('Grafica Valor del sensor de temperatura');             %Título que se le da a la gráfica
xlabel('Muestras en Segundos');                                    %Nombre del Eje x
ylabel('Temperatura (0.01°C)');                                 %Nombre del Eje y
hold on                                                %Retener la gráfica para que no se abra una nueva con cada dato
Numero_Muestras=2000;

while contador<=Numero_Muestras                        %Ciclo while para rellenar el vector ADC con los valores recibidos por el puerto serial
    recepcion=fscanf(serial_PSoC,'%f')'              %Asi se recibe un valor float por el puerto serial, es un vector columna.
    ADC(contador)=recepcion(1);                        %Asignacion de el vector recepción en la posicion 1 en el vector ADC en la posición en que se encuentre el contador
    plot(ADC)                                          %grafica los valores del vector ADC
    grid on                                            %Para poner la malla en la gráfica
    ylim([0 4000]);                                     %límites inferior y superior de la grafica en el eje y
    xlim([0 Numero_Muestras]);                         %límites inferior y superior de la grafica en el eje x
    drawnow                                            %Para actualizar los parámetros de la gráfica cada vez que pasa por el loop, ya que si no se pone
                                                       %unicamente con la función plot la imprimir{ia hasta que el loop se acabe
    contador=contador+1;                               %se modifica el contador para rellenar la siguiente posicion del vector ADC
    
    if contador>Numero_Muestras                       %condición para reiniciar el contador cuando se llega al número de muestras total                    
        hold off                                       %para "despegarse" de la gráfica un momento mientras el contador toma su valor inicial
                                                       %y asi cuando el loop vuelva a iniciarse se dara un efecto de osciloscopio                                                      %loop vuelva a
fclose(serial_PSoC);                                    %asi se cierra el puerto
delete(serial_PSoC);                                   %así se borra el puerto de la memoria de matlab
    end
end
    

PID

C/C++
This is the PID made in MATLAB
/* Header File Includes */
#include <project.h>
#include <stdio.h>
#define ADC_CHANNEL_VREF			(0u)
#define ADC_CHANNEL_VTH				(1u)
#define LED_ON						(0u)
#define LED_OFF						(1u)
#define TEMPERATURE_THRESHOLD_HIGH	(3000)
#define TEMPERATURE_THRESHOLD_LOW	(2500)
/* IIR Filter coefficients for each signal */
/* Cut off frequency = fs/(2 * pi * iir_filter_constant).  In this project fs ~= 1 ksps.
This results in a cut-off frequency of 4.97 Hz.  We are using IIR filter as FIR requires 
more order of filter to get the same cut-off frequency*/
#define FILTER_COEFFICIENT_TEMPERATURE	(32u)
/* EzI2C Read/Write Boundary */
#define READ_WRITE_BOUNDARY         (0u)
#define CAPACITANCE_AT_55_RH        (1800)
/* Sensitivity numerator and denominator indicate sensitivity of the sensor */
#define SENSITIVITY_NUMERATOR       (31)
#define SENSITIVITY_DENOMINATOR     (100)
/* Value of reference capacitor.  Note that this value includes the pin capacitance
    and the physical 180pF reference capacitor */
#define CREF                        (1930)
/* Offset Capacitance */
#define COFFSET                     (150)
/* This is raw count equivalent to trace capacitance */
#define OFFSETCOUNT                 (1536)
#define BUFFERSIZE                  (8)
/* Nominal humidity 55% */
#define NOMINAL_HUMIDITY            (550)
#define HUMIDITY_0_PERCENT          (0)
#define HUMIDITY_100_PERCENT        (1000)
#define HUMIDITY_50                 (500)   

/* Structure that holds the temperature sensor (thermistor) data                 */
/* Use __attribute__((packed)) for GCC and MDK compilers to pack structures      */
/* For other compilers use the corresponding directive.                          */
/* For example, for IAR use the following directive                              */
/* typedef __packed struct {..}struct_name;                                      */
typedef struct __attribute__((packed))
{
	int16 Vth;					/* Voltage across thermistor */
	uint16 Rth;					/* Thermistor resistance */
	int16 temperature;			/* Measured temperature */
    uint16 humidityRawCounts;	/* Raw count from CapSense Component for the humidity sensor */
	uint16 capacitance;			/* Capacitance of the humidity sensor */
	uint16 humidity;			/* Measured humidity */
	uint16 rawCountsRefCap;     /* Raw count from CapSense Component for the Reference capacitor */
}temperature_sensor_data;

/* Function Prototypes */
void InitResources(void);
__inline uint16 CalculateCapacitance(uint16 rawCounts, uint16 refSensorCounts);
__inline uint16 CalculateHumidity(uint16 capacitance);
/* Declare the i2cBuffer to exchange sensor data between Bridge Control 
Panel (BCP) and PSoC Analog Coprocessor */
temperature_sensor_data i2cBuffer = {0, 0, 0, 0, 0, 0, 0};

/*******************************************************************************
* Function Name: main
********************************************************************************
*
* Summary:
*  This function initializes all the resources, and in an infinite loop, measures the temperature from the sensor 
*  readings and to send the data over I2C.
*
* Parameters:
*  None
*
* Return:
*  int
*
* Side Effects:
*   None
*******************************************************************************/
int main()
{
    char stringBuffer[32u];
    /* Variables to hold the the ADC readings */
    int16 adcResultVREF, adcResultVTH;
    char setpoint;
    char m1=0,m2=0,m3=0,m4=0,m5=0,m6=0;
    char error;
    
    /* Filter input and output variables for Vref and Vth measurements */
    int16 filterOutputVref=0;
    int16 filterOutputVth=0;
    
    /* Variables to hold calculated resistance and temperature */
    int16 thermistorResistance, temperature;
    
    /* Variable to store the status returned by CyEnterCriticalSection()*/
    uint8 interruptState = 0;
    /* Variable to hold calculated PWM duty cycle */
    uint16 pwmDutyCycle;
    
    /* Enable global interrupts */
    CyGlobalIntEnable;
    
    /* Initialize hardware resources */
    InitResources();

    /* Infinite Loop */
    for(;;)
    {
        /* Check if the ADC data is ready */
        if(ADC_IsEndConversion(ADC_RETURN_STATUS))
        {
            /* Read the ADC result for reference and thermistor voltages */
            adcResultVREF = ADC_GetResult16(ADC_CHANNEL_VREF);
            adcResultVTH = ADC_GetResult16(ADC_CHANNEL_VTH);
            
            /* Low pass filter the measured ADC counts of Vref */            
            filterOutputVref = (adcResultVREF + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVref) / FILTER_COEFFICIENT_TEMPERATURE;
                    
            /* Low pass filter the measured ADC counts of Vth */         
            filterOutputVth = (adcResultVTH + (FILTER_COEFFICIENT_TEMPERATURE - 1) * filterOutputVth) / FILTER_COEFFICIENT_TEMPERATURE;
                        
            /* Calculate thermistor resistance */
            thermistorResistance = Thermistor_GetResistance(filterOutputVref, filterOutputVth);           
            
            /* Calculate temperature in degree Celsius using the Component API */
            temperature = Thermistor_GetTemperature(thermistorResistance);
            
            /* Turn ON Blue LED if Temperature is <= 25°C */ 
            if (temperature <= TEMPERATURE_THRESHOLD_LOW)
            {
                Pin_LED_Blue_Write(LED_ON);
                Pin_LED_Red_Write(LED_OFF);
            }
            /* Turn ON both Blue and Red LEDs if the temperature is >25°C and <=30°C */
            else if ((temperature > TEMPERATURE_THRESHOLD_LOW) && (temperature < TEMPERATURE_THRESHOLD_HIGH)) 
            {
                Pin_LED_Blue_Write(LED_ON);
                Pin_LED_Red_Write(LED_ON);
            }
            /* Turn ON Red LED if temperature is >30°C */
            else 
            {
                Pin_LED_Blue_Write(LED_OFF);
                Pin_LED_Red_Write(LED_ON);
            }   

            
			/* Enter critical section to check if I2C bus is busy or not */
            interruptState = CyEnterCriticalSection();
            
        	if(!(EZI2C_EzI2CGetActivity() & EZI2C_EZI2C_STATUS_BUSY))
        	{
                /* Update I2C Buffer */
                i2cBuffer.Rth = thermistorResistance;
                i2cBuffer.temperature = temperature;
                i2cBuffer.Vth = filterOutputVth;
                i2cBuffer.humidityRawCounts = CSD_BUTTON0_SNS0_RAW0_VALUE;
                i2cBuffer.rawCountsRefCap = CSD_BUTTON0_SNS1_RAW0_VALUE;
                /* Convert raw counts to capacitance */
                i2cBuffer.capacitance = CalculateCapacitance(i2cBuffer.humidityRawCounts, i2cBuffer.rawCountsRefCap);
                /* Calculate humidity */
                i2cBuffer.humidity = CalculateHumidity(i2cBuffer.capacitance);

            }
			
			/* Exit critical section */
            CyExitCriticalSection(interruptState);
        }

        /* Update the PWM duty cycle */
        
        uint16_t Temp1 = temperature;
        sprintf(stringBuffer, "%d",Temp1);  
        UART_UartPutString(stringBuffer);
        sprintf(stringBuffer, "%d",CalculateHumidity(i2cBuffer.capacitance));
        UART_UartPutString(stringBuffer);
        setpoint=UART_UartGetChar();
        //Controlador Pseudocodigo
        error=setpoint-temperature;
        m3=error;
        m1=m2+4.3381*m3-4.3381*(0.9983)*m4;
        m5=m4;
        m4=m3;
        m2=m1;
        VDAC_SetValue(m1);
        
        //Delay para generar el tiempo de muestreo
        CyDelay(20);
    }
}

/*******************************************************************************
* Function Name: void InitResources(void)
********************************************************************************
*
* Summary:
*  This function initializes all the hardware resources
*
* Parameters:
*  None
*
* Return:
*  None
*
* Side Effects:
*   None
*******************************************************************************/
void InitResources(void)
{
    /* Start EZI2C Slave Component and initialize buffer */
    EZI2C_Start();
    EZI2C_EzI2CSetBuffer1(sizeof(i2cBuffer), READ_WRITE_BOUNDARY, (uint8 *)&i2cBuffer);
        
    /* Start the Scanning SAR ADC Component and start conversion */
    ADC_Start();
    ADC_StartConvert();
    UART_Start();
    VDAC_Start();
    /* Start Reference buffer */
    VrefBuffer_Start();
    
    /* Start Programmable Voltage Reference */
    PVref_Start();
    
    /* Enable Programmable Voltage Reference */
    PVref_Enable();
        /* Start CapSense Component */
    CSD_Start();
    
    //Start PWM 
}

__inline uint16 CalculateCapacitance(uint16 rawCounts, uint16 refsensorCounts)
{
    return (uint16)((float)(rawCounts - OFFSETCOUNT) * (CREF - COFFSET) / (float)(refsensorCounts - OFFSETCOUNT));
}
__inline uint16 CalculateHumidity(uint16 capacitance)
{
    int16 humidity;
    int16 delta;

    /* Find capacitance difference from nominal capacitance at 55% RH */
    delta = capacitance - CAPACITANCE_AT_55_RH;
    
    /* Calculate humidity from capacitance difference and sensor sensitivity */
    humidity = ((delta * SENSITIVITY_DENOMINATOR) / SENSITIVITY_NUMERATOR) + NOMINAL_HUMIDITY;
    
    /* If humidity is less than zero, limit it to 0; If humidity is greater than 1000 (100%), limit to 1000 */
    humidity = (humidity < HUMIDITY_0_PERCENT) ? HUMIDITY_0_PERCENT : (humidity > HUMIDITY_100_PERCENT) ? HUMIDITY_100_PERCENT : humidity;

    /* Return Humidity value */
    return humidity;
}

/* [] END OF FILE */

Credits

Jeisson David Torrecilla A

Jeisson David Torrecilla A

2 projects • 5 followers

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