Hi,
ich denke, vor dem Lesen der Daten muss man mit einem Schreibbefehl die Registeradresse, ab der man lesen will, senden.
Also ich würde vor dem Lesen einmal die 0 (Sekundenregister) an die Slaveadresse senden und dann erst lesen.
Hallo liebes Forum,
ich versuche schon länger eine RTC (ein fertiges Modul -> I2C DS1307 wirklich Zeit Uhr Modul für Arduino Tiny RTC) mit einem Atmega1284p-pu über I2C auszulesen bzw erstmal zu stellen.
Da es nicht auf Anhieb mit der TWI_Master lib funktioniert hat, habe ich mit einem Oszi mal die SDA und SCL Leitungen gemessen und deren Daten ausgelesen. Ich konnte feststellen das er die Start condition und die richtige Adresse ( 0x68 ) anspricht und anschließend das Write-Bit sendet. Danach soll ein Acknolage von der RTC kommen doch ich bekomme immer ein Not-Acknolage. Woran könnte es liegen das die Uhr nicht antwortet?
Hier mein Code:
Bitte um Hilfe.Code:#define F_CPU 8000000UL #include <avr/io.h> #include <stdint.h> #include <util/delay.h> #include "lcd-routines.h" #include "General.h" #include "TWI_Master.h" #include <stdio.h> #include <util/twi.h> #include "ADC.h" #include "BinToDez.h" int main(void) { uint8_t SlaveAddress = 0x68; int8_t seconds, minutes, hours, day, date, month, year, control; int8_t sekunden, minuten, stunden, tag, monat, jahr; uint8_t i=0; char sekunden_string[2], minuten_string[2], stunden_string[2]; char tag_string[2], monat_string[2], jahr_string[2]; TWIM_Init (100000); // Initiate TWI Master with bitrate of 100000 Hz lcd_init(); //LCD initialisieren if (PINB & 0x01) { cli(); //Interrupts global ausschalten lcd_clear(); //Display löschen lcd_home(); //Coursor an den Anfang setzen //RTC Einstellen (einmalig) if (!TWIM_Start (SlaveAddress, TWIM_WRITE)) { TWIM_Stop (); } else { TWIM_Write (0b00000000); //Register-Pointer TWIM_Write (0b00000000); //sec TWIM_Write (0b01001000); //min TWIM_Write (0b00011001); //stunde TWIM_Write (0b00000011); //wochentag TWIM_Write (0b00000101); //tag TWIM_Write (0b00010110); //Monat TWIM_Write (0b00011001); //jahr TWIM_Write (0b00000000); //control TWIM_Stop (); _delay_ms(1000); } for (i = 0; i <=12; i++) { if (!TWIM_Start (SlaveAddress, TWIM_READ)) { TWIM_Stop (); } else { seconds = TWIM_ReadAck (); minutes = TWIM_ReadAck (); hours = TWIM_ReadAck (); day = TWIM_ReadAck (); date = TWIM_ReadAck (); month = TWIM_ReadAck (); year = TWIM_ReadAck (); control = TWIM_ReadNack (); TWIM_Stop (); _delay_ms(1000); } sekunden = BinToDez(seconds); //kann eventuell weg durch sprintf!!! sprintf(sekunden_string,"%d",sekunden); minuten = BinToDez(minutes); sprintf(minuten_string,"%d",minuten); stunden = BinToDez(hours); sprintf(stunden_string,"%d",stunden); tag = BinToDez(date); sprintf(tag_string,"%d",tag); monat = BinToDez(month); sprintf(monat_string,"%d",monat); jahr = BinToDez(year); sprintf(jahr_string,"%d",jahr); //Uhrzeit ausgeben lcd_string("Uhr: "); lcd_string(stunden_string); lcd_string(":"); lcd_string(minuten_string); lcd_string(":"); lcd_string(sekunden_string); //Nächste Zeile im LCD lcd_setcursor( 0, 2 ); //Datum ausgeben lcd_string("Datum:"); lcd_string(tag_string); lcd_string("."); lcd_string(monat_string); lcd_string(".20"); lcd_string(jahr_string); _delay_ms(250); //500ms warten lcd_home(); //LCD-coursor and Starposition setzen //Interrupts global an } } }
Gruß
Technik_Amateur
Geändert von Technik_Amateur (23.11.2013 um 17:35 Uhr)
Hi,
ich denke, vor dem Lesen der Daten muss man mit einem Schreibbefehl die Registeradresse, ab der man lesen will, senden.
Also ich würde vor dem Lesen einmal die 0 (Sekundenregister) an die Slaveadresse senden und dann erst lesen.
Gruß
Dirk
Hi Dirk,
Danke für deine Antwort. Jedoch scheitere ich schon beim Schreiben (stellen der Uhr). Wenn ich die Uhr nicht stellen kann, bringt mir das auslesen nicht viel. Oder kann es sein, dass die Uhr erst einmal ausgelesen werden muss, um initialisiert zu werden?
Gruß
Technik_Amateur
Wie wärs, wenn Du uns auch mal Deinen Code zum Schreiben/Lesen per I²C zeigst. Ich fürchte, dass da ein (DER?) Hund begraben liegt. Bei mir sehen z.B. die Schreib-/Lesebefehle so aus (Beispiel - läuft *gg*):... scheitere ich schon beim Schreiben (stellen der Uhr) ...Und !!! denk bitte dran, gelesen wird bei I²C immer von der ungraden Adresse . . . und natürlich wie Dirk schreibt, müsste dem Controller mitgegeben werden wo >vom Target< er denn lesen soll.Code:/** defines the data direction (writing to I2C device) in i2c_start(),i2c_rep_start() */ #define I2C_WRITE 0 /** defines the data direction (reading from I2C device) in i2c_start(),i2c_rep_start() */ #define I2C_READ 1 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - // Lesen vom Slave if(!(i2c_start(SLAVE_MoCo+I2C_WRITE))) //Slave bereit zum schreiben/lesen? { // // - - - - - - - - - - - - - - - - - - - - i2c_start(SLAVE_MoCo+I2C_WRITE); // Slave bereit zum schreiben/lesen? i2cdmy = i2c_write(0x00); // Buffer Startadresse 0 zum Auslesen i2c_stop(); // i2cdmy = i2c_start(SLAVE_MoCo+I2C_READ); // <<<### Lesen beginnen btst1 = i2c_read (ACK); // 1. von 5 Bytes lesen... btst2 = i2c_read (ACK); // btst3 = i2c_read (ACK); // btst4 = i2c_read (ACK); // btst5 = i2c_read (NAK); // letztes Byte lesen, darum NAK i2c_stop(); // Zugriff beenden } // else // Wenn Fehler, dann nelde jetzt: { // Lesefehler, dazu Fehlerblinken uputs0("\r\n\tKein Lesen möglich.\r\n"); // i2cerr = 0b00000001; // i2c-read nicht möglich for(i=0; i<2; i++) { // Fehlermeldung : LED i-fach blinken SetBit(PORTC, 2); // LED EIN, HELL waitms(3); // ClrBit(PORTC, 2); // LED AUS, Dunkel waitms(47); } // Ende for(i=0; i<..; i++) ==> LED ist AUS AUS } // Ende if(!(i2c_start(SLAVE_MoCo+I2C_WRITE))) // - - - - - - - - - - - - - - - - - - - -
Denn es sind immer ZWEI Adressen und Write ist nur die gerade Adresse.
Geändert von oberallgeier (24.11.2013 um 14:05 Uhr)
Ciao sagt der JoeamBerg
Ok also hier sind die 3 Datein, die ich zum I2C-beutzen verwende:
TWI_Master.h
TWI_Master.cCode:/******************************************************* Author: Manfred Langemann mailto: Manfred.Langemann ät t-online.de Begin of project: 04.01.2008 Latest version generated: 04.01.2008 Filename: TWI_Master.h Description: TWI Master functions include file ********************************************************/ #ifndef _TWIM #define _TWIM #define TWIM_READ 1 #define TWIM_WRITE 0 uint8_t TWIM_Init (uint32_t TWI_Bitrate); uint8_t TWIM_Start (uint8_t address, uint8_t TWIM_Type); void TWIM_Stop (void); uint8_t TWIM_Write (uint8_t byte); uint8_t TWIM_ReadAck (void); uint8_t TWIM_ReadNack (void); #endif
Und die dazugehörige General.hCode:/******************************************************* Author: Manfred Langemann mailto: Manfred.Langemann ät t-online.de Begin of project: 04.01.2008 Latest version generated: 04.01.2008 Filename: TWI_Master.c Description: TWI Master functions Master code adapted form Peter Fleury <pfleury@gmx.ch> http://jump.to/fleury -------------------------------------------------------- Program Example -------------------------------------------------------- int main (void) { uint8_t i=0; uint8_t j=0; uint8_t Data[8]; uint8_t SlaveAddress = 15; // Clear any interrupt cli (); // Wait 1 second for POR Delay_ms (1000); // Initiate RS232 RS232_Init (); printf ("Hello world...\n"); // Initiate TWI Master with bitrate of 100000 Hz TWIM_Init (100000); // Endless loop while (1) { // Read byte(s) from the slave. // It is implicitely assumed, that the slave will send // 8 bytes. if (!TWIM_Start (SlaveAddress, TWIM_READ)) { TWIM_Stop (); printf ("Could not start TWI Bus for READ\n"); } else { for (i=0;i<7;i++) { Data[i] = TWIM_ReadAck (); } Data[7] = TWIM_ReadNack (); printf ("Reading Byte %d: %d\n", i, Data[i]); TWIM_Stop (); Delay_ms (1000); } // Write byte(s) to the slave. // It is implicitely assumed, that the slave will // accepts 8 bytes if (!TWIM_Start (SlaveAddress, TWIM_WRITE)) { TWIM_Stop (); printf ("Could not start TWI Bus for WRITE\n"); } else { for (i=0;i<8;i++) { TWIM_Write (j++); printf ("Byte %d sent\n", j); } TWIM_Stop (); Delay_ms (1000); } // Do something else i++; } return 0; } ********************************************************/ #include <stdio.h> #include <avr/interrupt.h> #define F_CPU 8000000UL //auf 8MHz stellen? 1Mhz vllt zu langsam? //bei 1Mhz =-3 -> false, bei 8Mhz = 32 -> true! /*uint8_t TWIM_Init(uint32_t TWI_Bitrate) //uint8_t TWIM_Init (uint32_t TWI_Bitrate) { ** Set TWI bitrate ** If bitrate is too high, then error return *//* TWBR = ((F_CPU/TWI_Bitrate)-16)/2; if (TWBR < 11) return FALSE; return TRUE; }*/ #include "General.h" #include "TWI_Master.h" /**************************************************************************** TWI State codes ****************************************************************************/ // General TWI Master staus codes #define TWI_START 0x08 // START has been transmitted #define TWI_REP_START 0x10 // Repeated START has been transmitted #define TWI_ARB_LOST 0x38 // Arbitration lost // TWI Master Transmitter staus codes #define TWI_MTX_ADR_ACK 0x18 // SLA+W has been tramsmitted and ACK received #define TWI_MTX_ADR_NACK 0x20 // SLA+W has been tramsmitted and NACK received #define TWI_MTX_DATA_ACK 0x28 // Data byte has been tramsmitted and ACK received #define TWI_MTX_DATA_NACK 0x30 // Data byte has been tramsmitted and NACK received // TWI Master Receiver staus codes #define TWI_MRX_ADR_ACK 0x40 // SLA+R has been tramsmitted and ACK received #define TWI_MRX_ADR_NACK 0x48 // SLA+R has been tramsmitted and NACK received #define TWI_MRX_DATA_ACK 0x50 // Data byte has been received and ACK tramsmitted #define TWI_MRX_DATA_NACK 0x58 // Data byte has been received and NACK tramsmitted // TWI Slave Transmitter staus codes #define TWI_STX_ADR_ACK 0xA8 // Own SLA+R has been received; ACK has been returned #define TWI_STX_ADR_ACK_M_ARB_LOST 0xB0 // Arbitration lost in SLA+R/W as Master; own SLA+R has been received; ACK has been returned #define TWI_STX_DATA_ACK 0xB8 // Data byte in TWDR has been transmitted; ACK has been received #define TWI_STX_DATA_NACK 0xC0 // Data byte in TWDR has been transmitted; NOT ACK has been received #define TWI_STX_DATA_ACK_LAST_BYTE 0xC8 // Last data byte in TWDR has been transmitted (TWEA = “0”); ACK has been received // TWI Slave Receiver staus codes #define TWI_SRX_ADR_ACK 0x60 // Own SLA+W has been received ACK has been returned #define TWI_SRX_ADR_ACK_M_ARB_LOST 0x68 // Arbitration lost in SLA+R/W as Master; own SLA+W has been received; ACK has been returned #define TWI_SRX_GEN_ACK 0x70 // General call address has been received; ACK has been returned #define TWI_SRX_GEN_ACK_M_ARB_LOST 0x78 // Arbitration lost in SLA+R/W as Master; General call address has been received; ACK has been returned #define TWI_SRX_ADR_DATA_ACK 0x80 // Previously addressed with own SLA+W; data has been received; ACK has been returned #define TWI_SRX_ADR_DATA_NACK 0x88 // Previously addressed with own SLA+W; data has been received; NOT ACK has been returned #define TWI_SRX_GEN_DATA_ACK 0x90 // Previously addressed with general call; data has been received; ACK has been returned #define TWI_SRX_GEN_DATA_NACK 0x98 // Previously addressed with general call; data has been received; NOT ACK has been returned #define TWI_SRX_STOP_RESTART 0xA0 // A STOP condition or repeated START condition has been received while still addressed as Slave // TWI Miscellaneous status codes #define TWI_NO_STATE 0xF8 // No relevant state information available; TWINT = “0” #define TWI_BUS_ERROR 0x00 // Bus error due to an illegal START or STOP condition /******************************************************* Public Function: TWIM_Init Purpose: Initialise the TWI Master Interface Input Parameter: - uint16_t TWI_Bitrate (Hz) Return Value: uint8_t - FALSE: Bitrate too high - TRUE: Bitrate OK *******************************************************/ uint8_t TWIM_Init(uint32_t TWI_Bitrate) //uint8_t TWIM_Init (uint32_t TWI_Bitrate) { /* ** Set TWI bitrate ** If bitrate is too high, then error return */ TWBR = ((F_CPU/TWI_Bitrate)-16)/2; if (TWBR < 11) return FALSE; return TRUE; } /******************************************************* Public Function: TWIM_Start Purpose: Start the TWI Master Interface Input Parameter: - uint8_t Device address - uint8_t Type of required Operation: TWIM_READ: Read data from the slave TWIM_WRITE: Write data to the slave Return Value: uint8_t - TRUE: OK, TWI Master accessible - FALSE: Error in starting TWI Master *******************************************************/ uint8_t TWIM_Start (uint8_t Address, uint8_t TWIM_Type) { uint8_t twst; /* ** Send START condition */ TWCR = (1<<TWINT)|(1<<TWSTA)|(1<<TWEN); /* ** Wait until transmission completed */ while (!(TWCR & (1<<TWINT))); /* ** Check value of TWI Status Register. Mask prescaler bits. */ twst = TWSR & 0xF8; if ((twst != TWI_START) && (twst != TWI_REP_START)) return FALSE; /* ** Send device address */ TWDR = (Address<<1) + TWIM_Type; TWCR = (1<<TWINT)|(1<<TWEN); /* ** Wait until transmission completed and ACK/NACK has been received */ while (!(TWCR & (1<<TWINT))); /* ** Check value of TWI Status Register. Mask prescaler bits. */ twst = TWSR & 0xF8; if ((twst != TWI_MTX_ADR_ACK) && (twst != TWI_MRX_ADR_ACK)) return FALSE; return TRUE; } /******************************************************* Public Function: TWIM_Stop Purpose: Stop the TWI Master Input Parameter: None Return Value: None *******************************************************/ void TWIM_Stop (void) { /* ** Send stop condition */ TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWSTO); /* ** Wait until stop condition is executed and bus released */ while (TWCR & (1<<TWINT)); } /******************************************************* Public Function: TWIM_Write Purpose: Write a byte to the slave Input Parameter: - uint8_t Byte to be sent Return Value: uint8_t - TRUE: OK, Byte sent - FALSE: Error in byte transmission *******************************************************/ uint8_t TWIM_Write (uint8_t byte) { uint8_t twst; /* ** Send data to the previously addressed device */ TWDR = byte; TWCR = (1<<TWINT)|(1<<TWEN); /* ** Wait until transmission completed */ while (!(TWCR & (1<<TWINT))); /* ** Check value of TWI Status Register. Mask prescaler bits */ twst = TWSR & 0xF8; if (twst != TWI_MTX_DATA_ACK) return 1; return 0; } /******************************************************* Public Function: TWIM_ReadAck Purpose: Read a byte from the slave and request next byte Input Parameter: None Return Value: uint8_t - uint8_t Read byte *******************************************************/ uint8_t TWIM_ReadAck (void) { TWCR = (1<<TWINT)|(1<<TWEN)|(1<<TWEA); while (!(TWCR & (1<<TWINT))); return TWDR; } /******************************************************* Public Function: TWIM_ReadAck Purpose: Read the last byte from the slave Input Parameter: None Return Value: uint8_t - uint8_t Read byte *******************************************************/ uint8_t TWIM_ReadNack (void) { TWCR = (1<<TWINT)|(1<<TWEN); while(!(TWCR & (1<<TWINT))); return TWDR; }
GrußCode:#ifndef _General #define _General #define TRUE 1 #define FALSE 0 /* ** Here are some deinitions, used in all programs */ #define SYSCLOCK 8000000 // Quarz Frequenz in Hz #define SET_BIT(PORT, BITNUM) ((PORT) |= (1<<(BITNUM))) #define CLEAR_BIT(PORT, BITNUM) ((PORT) &= ~(1<<(BITNUM))) #define TOOGLE_BIT(PORT,BITNUM) ((PORT) ^= (1<<(BITNUM))) struct BitsOfByte { uint8_t b0:1; uint8_t b1:1; uint8_t b2:1; uint8_t b3:1; uint8_t b4:1; uint8_t b5:1; uint8_t b6:1; uint8_t b7:1; } __attribute__((__packed__)); #define SBIT(port,pin) ((*(volatile struct BitsOfByte*)&port).b##pin) #endif
Technik_Amatuer
Kann mir keiner helfen?
Gruß
Technik_Amateur
Zitat von Technik_Amateur
???Code:uint8_t SlaveAddress = 15;
MfG
Stefan
Das ist nur ein Beispiel, wie man diese lib verwendet. Sie ist auskommentiert. Meine Adress ist 0x68.
GrußCode:uint8_t SlaveAddress = 0x68;
Technik_Amateur
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