Temperatura cu 16F882 si AD5933

[Vizitator Mareshal]

Incerc sa iau temperatura de la un AD5933(http://www.analog.com/static/imported-f ... AD5933.pdf), sa vad macar ca imi functioneaza I2C-ul calumea.

 

Senzorul de temperatura(datasheet pagina 16, reda temperatura pe 16 biti, la dresele 0x92 si 0x93). Aveti un indiciu? Am nevoie de putin ajutor.

 

Momentan primesc: 40 si 255

 

Asta e codul pana acum:

 

#include <stdio.h>#include <math.h>#include <htc.h>#include "usart.h"#include "i2c.h"#define STATUS 0x00#define PCLATH 0x00#define _XTAL_FREQ 4000000 // Pic osc 4mhz#define startfreq 200	//Start Frequency#define incfreq 100	//Incremental Frequency#define SUCCESS 0xff	//Flag    //Command#define Start 0xA4#define Stop 0x94#define Trans 0x84#define ACK 0xC4 //AD5933 control codes#define Init 0x10	//Initialize with start Freq#define Sweep 0x20	//Start Frequency Sweep#define IncFreq 0x30	//Increment Frequency#define RepFreq 0x40	//Repeat Frequency#define MeaTemp 0x90	//Measure Temperature#define PowerDown 0xa0	//Power down mode#define Standby 0xb0	//Standby mode#define Range2V 0x00	//Output Voltage range 2V#define Range1V 0x06	//Output Voltage range 1V#define Range400mV 0x04 //Output Voltage range 400mV#define Range200mV 0x02 //Output Voltage range 200mV#define gainx5 0x00	//PGA gain x5#define gainx1 0x01	//PGA gain x1//AD5933 Register addresses#define Control_high 0x80#define Control_low 0x81#define Freq_high 0x82#define Freq_mid 0x83#define Freq_low 0x84#define FreqInc_high 0x85#define FreqInc_mid 0x86#define FreqInc_low 0x87#define NumInc_high 0x88#define NumInc_low 0x89#define NumSettle_high 0x8a#define NumSettle_low 0x8b#define Status 0x8f#define Temp_high 0x92#define Temp_low 0x93#define Real_high 0x94#define Real_low 0x95#define Imag_high 0x96#define Imag_low 0x97/****************************************************************************	Function : unsigned char Byte_write(unsigned char reg_addr, unsigned char data)	Write a byte to AD5933.****************************************************************************/unsigned char Byte_write(unsigned char reg_addr, unsigned char data){	i2c_Start();	i2c_PutByte(0x0D);	i2c_WriteTo(reg_addr);	i2c_PutByte(data);	i2c_Stop();	return 1;}/****************************************************************************	Function : unsigned char Byte_read(unsigned char reg_loc)	Read a byte from AD5933.****************************************************************************/unsigned char Byte_read(unsigned char reg_loc){	i2c_Start();	i2c_PutByte(0x0D);	i2c_ReadFrom(reg_loc);	//set the pointer location	return i2c_GetByte(I2C_MORE);	i2c_Stop();}     /****************************************************************************	Function : unsigned long int Data_proc(unsigned char data_high, unsigned char data_low)	Calculate the code value from AD5933.****************************************************************************/unsigned long int Data_proc(unsigned char data_high, unsigned char data_low){	unsigned long int data;	data=(unsigned long int)data_high*256+data_low;		if(data > 0x7fff)	{		data=0x10000-data;	}		return data;}/****************************************************************************	Function : void Display(unsigned long int frequency, unsigned long int impedance)	A function used to display the measured results.****************************************************************************/void Display(unsigned long int frequency, unsigned long int impedance){    	printf("freq: %li, imp: %li", frequency, impedance);} void main(){			TRISA = 0x00;	RA0 = 0xFF;	//USART	INTCON=0;	// purpose of disabling the interrupts.	init_comms();	// set up the USART - settings defined in usart.h		// Declare your local variables here	unsigned char i,a,b, t1, t2;	unsigned long int R,I,T;		//Real and Imag numbers		unsigned long int impedance;	//Refence Impedance values used in the system	unsigned long int ReImpedance[]={200000};	//Analog switches control code	float code,Calcode; // I2C Bus initialization//i2c_Start();// Global enable interrupts		while(1) {						//printf("me ");								// Place your code here				//set start frequency      	      	 Byte_write(Freq_low, 0x00);      	    	 Byte_write(Freq_mid ,0x19);      	    	 Byte_write(Freq_high, 0x00);                      	 	//set Incremental frequency               	Byte_write(FreqInc_low,0x00);            	Byte_write(FreqInc_mid,0xC0);            	Byte_write(FreqInc_high,0x80); 			            	//Set Num of Inc            	Byte_write(NumInc_high, 0x00);            	Byte_write(NumInc_low, 0x63);                        	//Set Num of Settling Time Cycles            	Byte_write(NumSettle_high, 0x02);            	Byte_write(NumSettle_low,0x01);                        	//Working mode				Byte_write(Control_low, 0x00);            	Byte_write(Control_high, 0xb0);          	            Byte_write(Control_high, 0x10);              	Byte_write(Control_high, 0x20);            	while(!(Byte_read(Status) & 0x02));                        //	a=Byte_read(Real_high);            //	b=Byte_read(Real_low);            	           //		printf("%i %i", a, b);           // 	R=Data_proc(a, b);           // 	a=Byte_read(Imag_high);          //  	b=Byte_read(Imag_low);          //  	I=Data_proc(a, b);            	            t1=Byte_read(Temp_high);           t2=Byte_read(Temp_low);           T=Data_proc(t1, t2);           printf("t1=%i, t2=%i, T=%i :: ", t1, t2, T);	}}void interrupt isr(){}	// to avoid bootloader overwrite.

[Liviu M]

/**************************************************************************** Function : unsigned char Byte_write(unsigned char reg_addr, unsigned char data) Write a byte to AD5933.****************************************************************************/unsigned char Byte_write(unsigned char reg_addr, unsigned char data){ i2c_Start(); i2c_PutByte(0x0D); i2c_WriteTo(reg_addr); i2c_PutByte(data); i2c_Stop(); return 1;}/**************************************************************************** Function : unsigned char Byte_read(unsigned char reg_loc) Read a byte from AD5933.****************************************************************************/unsigned char Byte_read(unsigned char reg_loc){ i2c_Start(); i2c_PutByte(0x0D); i2c_ReadFrom(reg_loc); //set the pointer location return i2c_GetByte(I2C_MORE); i2c_Stop();}.[/code]

La i2c, bitul LSB din adresa indica operatia - 0 pentru scris, 1 pentru citit . Tu si la read si la write trimiti aceeasi (banuiesc) adresa - 0x0D. Daca nu faci prin functii nici un artificiu, s-ar putea ca de aici sa-ti vina o parte din probleme.

[Vizitator Mareshal]

Codul original a fost tradus de la un ATMEGA: http://www.avrfreaks.net/index.php?name ... 80&start=0

 

Cred ca am omis niste chestii

[Liviu M]

Probabil te-ai incurcat la

Send_adr(SLA_W);

pentru scris si

Send_adr(SLA_R);   

pentru citit.

 

Adresa senzorului fiind 0001101 (7 biti), pentru tine SLA_W = 00011010 = 0x1A si SLA_R = 00011011 = 0x1B.

Din cauza ca bitul LSB al "adresei" indica operatia, adresa pentru scriere e intotdeauna para, cea de citire impara (asta asa, ca verificare rapida).

 

LE Ca sa vezi cum se socotesc adresele astea poti sa te uiti la pagina 28 din data-sheetul pe care l-ai postat mai sus.