USI_TWI_Master.h File Reference

---

Detailed Description

Atmel Corporation

• File : USI_TWI_Master.h
• 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_Start_Transceiver_With_Data() function. If the transceiver returns with a fail, then use USI_TWI_Get_State_Info() to evaluate the couse of failure.

Revision

1.3

Date

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

Definition in file USI_TWI_Master.h.

#include <iotiny24.h>

Include dependency graph for USI_TWI_Master.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	tx_type
Defines
#define	DDR_USI   DDRA
#define	FALSE   0
#define	OWN_ADR   60
#define	PIN_USI   PINA
#define	PIN_USI_SCL   PINA4
#define	PIN_USI_SDA   PINA6
#define	PORT_USI   PORTA
#define	PORT_USI_SCL   PORTA4
#define	PORT_USI_SDA   PORTA6
#define	R   1
#define	SUCCESS   0xFF
#define	SYS_CLK   1000.0
#define	T2_TWI   ((SYS_CLK *4700) /1000000) +1
#define	T4_TWI   ((SYS_CLK *4000) /1000000) +1
#define	TRUE   1
#define	TWI_ADR_BITS   1
#define	TWI_NACK_BIT   0
#define	TWI_READ_BIT   0
#define	USI_TWI_DATA_OUT_OF_BOUND   0x01
#define	USI_TWI_MISSING_START_CON   0x07
#define	USI_TWI_MISSING_STOP_CON   0x08
#define	USI_TWI_NO_ACK_ON_ADDRESS   0x06
#define	USI_TWI_NO_ACK_ON_DATA   0x05
#define	USI_TWI_NO_DATA   0x00
#define	USI_TWI_UE_DATA_COL   0x04
#define	USI_TWI_UE_START_CON   0x02
#define	USI_TWI_UE_STOP_CON   0x03
#define	W   0
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_Start_Transceiver_With_Data (unsigned char *, unsigned char)

---

Define Documentation

#define DDR_USI   DDRA

Definition at line 83 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Initialise(), USI_TWI_Master_Transfer(), and USI_TWI_Start_Transceiver_With_Data().

#define FALSE   0

Definition at line 92 of file USI_TWI_Master.h. Referenced by LCD_Init(), LCD_PutXY_Raw(), LCD_WriteLine(), USI_TWI_LCD_Test(), USI_TWI_Master_Stop(), and USI_TWI_Start_Transceiver_With_Data().

#define OWN_ADR   60

Definition at line 65 of file USI_TWI_Master.h.

#define PIN_USI   PINA

Definition at line 85 of file USI_TWI_Master.h. Referenced by USI_TWI_Master_Stop(), and USI_TWI_Master_Transfer().

#define PIN_USI_SCL   PINA4

Definition at line 89 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Initialise(), USI_TWI_Master_Stop(), USI_TWI_Master_Transfer(), and USI_TWI_Start_Transceiver_With_Data().

#define PIN_USI_SDA   PINA6

Definition at line 88 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Initialise(), USI_TWI_Master_Stop(), USI_TWI_Master_Transfer(), and USI_TWI_Start_Transceiver_With_Data().

#define PORT_USI   PORTA

Definition at line 84 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Initialise(), USI_TWI_Master_Stop(), and USI_TWI_Start_Transceiver_With_Data().

#define PORT_USI_SCL   PORTA4

Definition at line 87 of file USI_TWI_Master.h.

#define PORT_USI_SDA   PORTA6

Definition at line 86 of file USI_TWI_Master.h.

#define R   1

Definition at line 64 of file USI_TWI_Master.h.

#define SUCCESS   0xFF

Definition at line 66 of file USI_TWI_Master.h.

#define SYS_CLK   1000.0

Definition at line 40 of file USI_TWI_Master.h.

#define T2_TWI   ((SYS_CLK *4700) /1000000) +1

Definition at line 47 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Stop(), USI_TWI_Master_Transfer(), and USI_TWI_Start_Transceiver_With_Data().

#define T4_TWI   ((SYS_CLK *4000) /1000000) +1

Definition at line 48 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Stop(), USI_TWI_Master_Transfer(), and USI_TWI_Start_Transceiver_With_Data().

#define TRUE   1

Definition at line 91 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), USI_TWI_Master_Stop(), and USI_TWI_Start_Transceiver_With_Data().

#define TWI_ADR_BITS   1

Definition at line 69 of file USI_TWI_Master.h.

#define TWI_NACK_BIT   0

Definition at line 70 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), and USI_TWI_Start_Transceiver_With_Data().

#define TWI_READ_BIT   0

Definition at line 68 of file USI_TWI_Master.h. Referenced by LCD_Init(), LCD_PutXY_Raw(), LCD_WriteLine(), USI_TWI_LCD_Test(), and USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_DATA_OUT_OF_BOUND   0x01

Definition at line 73 of file USI_TWI_Master.h. Referenced by USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_MISSING_START_CON   0x07

Definition at line 79 of file USI_TWI_Master.h. Referenced by USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_MISSING_STOP_CON   0x08

Definition at line 80 of file USI_TWI_Master.h. Referenced by USI_TWI_Master_Stop().

#define USI_TWI_NO_ACK_ON_ADDRESS   0x06

Definition at line 78 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), and USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_NO_ACK_ON_DATA   0x05

Definition at line 77 of file USI_TWI_Master.h. Referenced by USI_TWI_LCD_Test(), and USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_NO_DATA   0x00

Definition at line 72 of file USI_TWI_Master.h. Referenced by USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_UE_DATA_COL   0x04

Definition at line 76 of file USI_TWI_Master.h. Referenced by USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_UE_START_CON   0x02

Definition at line 74 of file USI_TWI_Master.h. Referenced by USI_TWI_Start_Transceiver_With_Data().

#define USI_TWI_UE_STOP_CON   0x03

Definition at line 75 of file USI_TWI_Master.h. Referenced by USI_TWI_Start_Transceiver_With_Data().

#define W   0

Definition at line 63 of file USI_TWI_Master.h.

---

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_Start_Transceiver_With_Data (  unsigned char *  , unsigned  char )

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().

---