pid files

2nd and 3rd channel can be coupled via percentage

i2c.h

@@ -15,7 +15,7 @@
 	#define SDA_PIN			PC4 //PIN am Atmel
 	#define SCL_PIN			PC5 //PIN am Atmel
 	#define I2C_PORT		PORTC //PORT am Atmel
-	#define SCL_CLOCK		100000UL
+	#define SCL_CLOCK		40000UL
 
 	void i2c_init(void);
 	uint8_t i2c_start (uint8_t);
@@ -23,4 +23,4 @@
 	uint8_t i2c_readNak(void);
 	void i2c_stop (void);
 
-#endif /* I2C_H_ */
+#endif /* I2C_H_ */

lcd.c

@@ -107,6 +107,7 @@ void lcd_init() {
 	lcd_nibble_out(0x0C, 0);
 
 	lcd_clear();
+    lcd_cursor(0);
 }
 
 //***************************************************************************************

main.c

@@ -14,18 +14,38 @@
 #include "modbus.h"
 #include "menu.h"
 #include "adc.h"
+#include "pid.h"
+
+#define COIL1 1<<1
+#define COIL2 1<<0
+#define COIL3 1<<2
+#define COIL4 1<<3
 
 volatile uint16_t holdingRegisters[10];
 
 volatile uint16_t temp_values[4];
 volatile uint16_t temp_setpoints[4];
 
+volatile uint16_t output;
+volatile struct pid controller;
+
+volatile uint32_t duty[3];
+
 void modbusGet(void) {
 	if (modbusGetBusState() & (1<<ReceiveCompleted))
 	{
         switch(rxbuffer[1]) {
             case fcReadHoldingRegisters:
-                holdingRegisters[0] = menu_state;
+                holdingRegisters[0] = duty[0];
+                holdingRegisters[1] = duty[1];
+                holdingRegisters[2] = duty[2];
+
+                holdingRegisters[3] = temp_values[0];
+                holdingRegisters[4] = temp_values[1];
+                holdingRegisters[5] = temp_values[2];
+
+                modbusExchangeRegisters(holdingRegisters,0,10);
+                break;
             case fcPresetSingleRegister:
             case fcPresetMultipleRegisters:
                 modbusExchangeRegisters(holdingRegisters,0,4);
@@ -38,7 +58,7 @@ void modbusGet(void) {
 	}
 }
 
-void do_buttons(){
+void read_buttons(){
     i2c_start(0x71);
     uint8_t buttons = i2c_readNak();
     i2c_stop();
@@ -54,62 +74,143 @@ void do_buttons(){
         set_item(4);
     else if(buttons & (1 << 4))
         set_item(5);
+    else if((buttons & (1 << 5)) == 0) // inverted logic on this one
+        set_item(0);
+
 }
 
 int main(void)
 {
+    DDRB |= 0x0F;       // output coils
+    DDRD |= (1 << 4);   // board LED
+
 	i2c_init();
 	lcd_init();
     adc_init();
-	
-	lcd_clear();
+    enc_init();
+
+    init_pid(&controller, 1, 0.05, 0);
 
-    sei();
     modbusSetAddress(1);
     modbusInit();
 
-    TCCR0B|=(1<<CS01); //prescaler 8
+    //modbus timer
+    TCCR0B|=(1<<CS01);
 	TIMSK0|=(1<<TOIE0);
 
-    PORTD |= (1<<6) | (1 << 7);
-    PCICR |= (1<<PCIE2);
-    PCMSK2 |= (1<<PCINT23);
+    // timer for regulator
+    TCCR1B|=(1<<CS12) | (1<<CS10);
+	TIMSK1|=(1<<TOIE1)|(1<<OCIE1A);
+
+    sei();
 
+	lcd_clear();
     draw_menu();
 
+
     uint16_t x = 0;
 	while(1){
         modbusGet();
-        do_buttons();
+        read_buttons();
+
+        //blink cursor
         if(x==0){
+        //}
+        ////write values
+        //if(x % 2048 == 0){
+            lcd_cursor(0);
             write_temps();
             write_setpoints();
+            write_motor();
             update_cursor();
         }
         x++;
-        if(x>=2024)
+        if(x >= 1024)
             x=0;
 	}
 }
 
+ISR(PCINT2_vect){
+    encoder_isr();
+}
+
 ISR(TIMER0_OVF_vect) { //this ISR is called 9765.625 times per second
 	modbusTickTimer();
 }
 
-ISR(PCINT2_vect){
-    //TODO good quadrature reading code
-    if((PIND & (1<<7)) && (menu_state >= 1) && (menu_state <= 3)){
-        if(PIND & (1<<6))
-            temp_setpoints[menu_state-1]--;
-        else
-            temp_setpoints[menu_state-1]++;
+ISR(TIMER1_COMPA_vect) {
+    /* turn off outputs */
+
+    if(OCR1A >= duty[0]){
+        PORTB &= ~(COIL1);
+        PORTD &= ~(1 << 4);
+    }
+    if(OCR1A >= duty[1])
+        PORTB &= ~(COIL2);
+    if(OCR1A >= duty[2])
+        PORTB &= ~(COIL3);
+
+    uint16_t new_ocr = 0xFFFE;
+    for(uint8_t i = 0; i < 3; i++){
+        if((duty[i] > OCR1A) && (duty[i] < new_ocr))
+            new_ocr = duty[i];
+    }
+    OCR1A = new_ocr;
+
+    //uint16_t tmp1 = duty[0];
+    //uint16_t tmp2;
+    //for(uint8_t i = 0; i < 3; i++){
+    //    if(duty[i] < tmp1 && duty[i] > OCR1A)
+    //        tmp2 = duty[i];
+    //}
+    //OCR1A = tmp2;
+}
+
+ISR(TIMER1_OVF_vect) {
+    int16_t tmp_pid = pid_step(&controller, 1, temp_setpoints[0] - temp_values[0]);
+    
+    if(tmp_pid>=0)
+        output = tmp_pid;
+    else
+        output = 0;
+
+
+    if(output >= 128){
+        output = 128;
+        duty[0]=0xFFFE;
+    }
+    else if(output >= 1){
+        uint32_t tmp = output * 512;
+        duty[0] = tmp;
     }
+    else
+        duty[0]=0;
+
+
+    duty[1] = duty[0] / 100 * temp_setpoints[1];
+    duty[2] = duty[0] / 100 * temp_setpoints[2];
+
+    for(uint8_t i = 0; i < 3; i++){
+        if(duty[i] >= 0xFFFE)
+            duty[i] = 0xFFFE;
+    }
+
+    OCR1A = 0xFFFE;
+    for(uint8_t i = 0; i < 3; i++){
+        if(duty[i] < OCR1A && duty[i] >= (uint16_t)1000)
+            OCR1A = duty[i];
+    }
+
+    if(duty[0] >= 1000){
+        PORTB |= COIL1;
+        PORTD |= 1<<4;
+    }
+    if(duty[1] >= 1000)
+        PORTB |= COIL2;
+
+    if(duty[2] >= 1000)
+        PORTB |= COIL3;
+
 
-    //if(PIND & (1<<7))
-    //    if(PIND & (1<<6)){
-    //        if(temp_setpoints[menu_state] > 0)
-    //    }
-    //    else{
-    //        if(temp_setpoints[menu_state] < 300)
-    //    }
 }
+

makefile

@@ -1,5 +1,5 @@
 TARGET  = main
-FILES   = main i2c lcd modbus menu adc
+FILES   = main i2c lcd modbus menu adc pid
 MCU     = atmega328p
 PROGC	= m328p
 CC      = avr-gcc

menu.c

@@ -19,15 +19,23 @@ void write_heater_set_temp(uint8_t n, uint16_t temp){
 void update_cursor(){
     switch(menu_state){
         case 1:
-            lcd_set_position(2,6);
+            lcd_set_position(0,5);
             lcd_cursor(1); 
             break;
         case 2:
-            lcd_set_position(2,11);
+            lcd_set_position(0,9);
             lcd_cursor(1); 
             break;
         case 3:
-            lcd_set_position(2,16);
+            lcd_set_position(0,14);
+            lcd_cursor(1); 
+            break;
+        case 4:
+            lcd_set_position(2,9);
+            lcd_cursor(1); 
+            break;
+        case 5:
+            lcd_set_position(3,9);
             lcd_cursor(1); 
             break;
         default:
@@ -38,45 +46,60 @@ void update_cursor(){
 
 void draw_menu(){
 	lcd_clear();
-    lcd_write(" Heat Zone Control");
+    lcd_set_position(0, 0);
+    lcd_write("s:");
+    lcd_set_position(1, 0);
+    lcd_write("r:");
     lcd_set_position(2, 0);
-    lcd_write(" set:");
+    lcd_write("motor:");
     lcd_set_position(3, 0);
-    lcd_write("real:");
-    //char str[16];
-    //sprintf(str, "test %d", 1);
-    //lcd_print_str(str);
+    lcd_write("fan  :");
+}
+
+void write_motor(){
+    char str[5];
+    str[4] = 0; //null terminated
+
+    lcd_set_position(2, 7);
+    sprintf(str, "%3i", OCR2B);
+    lcd_print_str(str);
 }
 
 void write_temps(){
-    char str[4];
+    char str[5];
+    str[4] = 0; //null terminated
 
-    lcd_set_position(3, 6);
+    lcd_set_position(1, 3);
     sprintf(str, "%3i", temp_values[0]);
+    str[3] = 0xDF;
     lcd_print_str(str);
 
-    lcd_set_position(3, 11);
+    lcd_set_position(1, 7);
     sprintf(str, "%3i", temp_values[1]);
+    str[3] = 0xDF;
     lcd_print_str(str);
 
-    lcd_set_position(3, 16);
+    lcd_set_position(1, 12);
     sprintf(str, "%3d", temp_values[2]);
+    str[3] = 0xDF;
     lcd_print_str(str);
 }
 
 void write_setpoints(){
-    char str[4];
+    char str[5];
+    str[4] = 0; //null terminated
 
-    lcd_set_position(2, 6);
+    lcd_set_position(0, 3);
     sprintf(str, "%3i", temp_setpoints[0]);
+    str[3] = 0xDF;
     lcd_print_str(str);
 
-    lcd_set_position(2, 11);
-    sprintf(str, "%3i", temp_setpoints[1]);
+    lcd_set_position(0, 7);
+    sprintf(str, "%3i%%", temp_setpoints[1]);
     lcd_print_str(str);
 
-    lcd_set_position(2, 16);
-    sprintf(str, "%3i", temp_setpoints[2]);
+    lcd_set_position(0, 12);
+    sprintf(str, "%3i%%", temp_setpoints[2]);
     lcd_print_str(str);
 }
 
@@ -84,6 +107,39 @@ void set_item(uint8_t page_num){
     //if(menu_state=page_num)
     //    menu_state=0;
     //else
-        menu_state = page_num;
+    menu_state = page_num;
 }
 
+void enc_init(){
+    PORTD |= (1<<6) | (1 << 7);
+    PCICR |= (1<<PCIE2);
+    PCMSK2 |= (1<<PCINT23);
+}
+
+
+
+void encoder_isr(){
+    //TODO good quadrature reading code
+    if((PIND & (1<<7))){
+        if((menu_state >= 1) && (menu_state <= 3)){
+            if(PIND & (1<<6))
+                temp_setpoints[menu_state-1]--;
+            else
+                temp_setpoints[menu_state-1]++;
+        }
+        if(menu_state == 4){
+            if(PIND & (1<<6) && (OCR2B > 0))
+                OCR2B--;
+            else if(!(PIND & (1<<6)) && (OCR2B < 255))
+                OCR2B++;
+        }
+    }
+
+    //if(PIND & (1<<7))
+    //    if(PIND & (1<<6)){
+    //        if(temp_setpoints[menu_state] > 0)
+    //    }
+    //    else{
+    //        if(temp_setpoints[menu_state] < 300)
+    //    }
+}

menu.h

@@ -8,8 +8,11 @@ extern volatile uint16_t temp_setpoints[4];
 
 void write_temps(void);
 void write_setpoints(void);
+void write_motor(void);
 void update_cursor(void);
 void set_item(uint8_t page_num);
 void draw_menu(void);
+void enc_init(void);
+void encoder_isr(void);
 
 #endif

pid.c

@@ -0,0 +1,36 @@
+#include <util/atomic.h>
+#include "pid.h"
+
+extern volatile uint16_t holdingRegisters[10];
+int16_t pid_step(volatile struct pid* controller, float dt, int16_t error) {
+    // Calculate p term
+
+    uint16_t p = error * controller->kP;
+
+    // Calculate i term
+    ATOMIC_BLOCK(ATOMIC_FORCEON){
+        controller->integral += error * dt * controller->kI;
+        if(controller->integral > 80)
+            controller->integral = 80;
+        if(controller->integral < -80)
+            controller->integral = -80;
+    }
+    //holdingRegisters[3]=((float)(error) * controller->kI);
+    //holdingRegisters[4] = error;
+
+    // Calculate d term, taking care to not divide by zero
+    float d = dt == 0 ? 0 : ((error - controller->lastError) / dt) * controller->kD;
+    controller->lastError = error;
+
+    return p + controller->integral + d;
+}
+
+void init_pid(volatile struct pid* controller, float p, float i, float d){
+    *controller = (struct pid){
+        .kP = p,
+        .kI = i,
+        .kD = d,
+        .lastError = 0,
+        .integral = 0
+    };
+}

pid.h

@@ -0,0 +1,21 @@
+#ifndef _PID_H_
+#define _PID_H_
+
+#include <stdint.h>
+
+struct pid{
+    // Controller gains
+    float kP;
+    float kI;
+    float kD;
+
+    // State variables
+    float lastError;
+    float integral;
+};
+
+//float pid_step(volatile struct pid* controller, float dt, float error);
+int16_t pid_step(volatile struct pid* controller, float dt, int16_t error);
+void init_pid(volatile struct pid* controller, float p, float i, float d);
+
+#endif