USI_TWI_Master.c File Reference

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Detailed Description

Atmel Corporation

• File : USI_TWI_Master.c
• Compiler : IAR EWAVR 4.11A

• Support mail : avr@atmel.com

• Supported devices : This example is written for the ATtiny24.

• AppNote : AVR245: Code Lock with LCD.
• Related AppNote : AVR310 - Using the USI module as a TWI Master

• Description : This is an implementation of an TWI master using the USI module as basis. The implementation assumes the AVR to be the only TWI master in the system and can therefore not be used in a multi-master system.

• Usage : Initialize the USI module by calling the USI_TWI_Master_Initialise() function. Hence messages/data are transceived on the bus using the USI_TWI_Transceive() function. The transceive function returns a status byte, which can be used to evaluate the success of the transmission.

Revision

1.3

Date

Monday, October 10, 2005 13:23:34 UTC

Definition in file USI_TWI_Master.c.

#include <inavr.h>
#include <iotiny24.h>
#include "USI_TWI_Master.h"

Include dependency graph for USI_TWI_Master.c:

Go to the source code of this file.

Functions
__interrupt void	USI_START_ISR (void)
unsigned char	USI_TWI_Get_State_Info (void)
unsigned char	USI_TWI_LCD_Test (void)
void	USI_TWI_Master_Initialise (void)
unsigned char	USI_TWI_Master_Stop (void)
unsigned char	USI_TWI_Master_Transfer (unsigned char)
unsigned char	USI_TWI_Start_Transceiver_With_Data (unsigned char *msg, unsigned char msgSize)
Variables
USI_TWI_state	USI_TWI_state

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Function Documentation

__interrupt void USI_START_ISR (  void   )

Definition at line 51 of file USI_TWI_Master.c.

unsigned char USI_TWI_Get_State_Info (  void   )

Definition at line 82 of file USI_TWI_Master.c. References USI_TWI_state.

unsigned char USI_TWI_LCD_Test (  void   )

Definition at line 218 of file USI_TWI_Master.c. References DDR_USI, FALSE, PIN_USI_SCL, PIN_USI_SDA, PORT_USI, T2_TWI, T4_TWI, TRUE, TWI_NACK_BIT, TWI_READ_BIT, USI_TWI_Master_Stop(), USI_TWI_Master_Transfer(), USI_TWI_NO_ACK_ON_ADDRESS, USI_TWI_NO_ACK_ON_DATA, and USI_TWI_state.

void USI_TWI_Master_Initialise (  void   )

Definition at line 59 of file USI_TWI_Master.c. References DDR_USI, PIN_USI_SCL, PIN_USI_SDA, and PORT_USI. Referenced by Initialise().

unsigned char USI_TWI_Master_Stop (  void   )

Definition at line 352 of file USI_TWI_Master.c. References FALSE, PIN_USI, PIN_USI_SCL, PIN_USI_SDA, PORT_USI, T2_TWI, T4_TWI, TRUE, USI_TWI_MISSING_STOP_CON, and USI_TWI_state. Referenced by USI_TWI_LCD_Test(), and USI_TWI_Start_Transceiver_With_Data().

unsigned char USI_TWI_Master_Transfer (  unsigned  char  )

Definition at line 320 of file USI_TWI_Master.c. References DDR_USI, PIN_USI, PIN_USI_SCL, PIN_USI_SDA, T2_TWI, and T4_TWI. Referenced by USI_TWI_LCD_Test(), and USI_TWI_Start_Transceiver_With_Data().

unsigned char USI_TWI_Start_Transceiver_With_Data (  unsigned char *  msg, unsigned char  msgSize )

Definition at line 100 of file USI_TWI_Master.c. References DDR_USI, FALSE, PIN_USI_SCL, PIN_USI_SDA, PORT_USI, T2_TWI, T4_TWI, TRUE, TWI_NACK_BIT, TWI_READ_BIT, USI_TWI_DATA_OUT_OF_BOUND, USI_TWI_Master_Stop(), USI_TWI_Master_Transfer(), USI_TWI_MISSING_START_CON, USI_TWI_NO_ACK_ON_ADDRESS, USI_TWI_NO_ACK_ON_DATA, USI_TWI_NO_DATA, USI_TWI_state, USI_TWI_UE_DATA_COL, USI_TWI_UE_START_CON, and USI_TWI_UE_STOP_CON. Referenced by LCD_Init(), LCD_PutXY_Raw(), and LCD_WriteLine().

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Variable Documentation

union USI_TWI_state USI_TWI_state

Referenced by USI_TWI_Get_State_Info(), USI_TWI_LCD_Test(), USI_TWI_Master_Stop(), and USI_TWI_Start_Transceiver_With_Data().

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