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
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