Nothing.

Initializes I²C with desired clock (refer to device data sheet for correct values in respect with Fosc). Needs to be called before using other functions of I²C Library.

You don’t need to configure ports manually for using the module; library will take care of the initialization.

  Note :

• Calculation of the I²C baud rate value is carried out by the compiler, as it would produce a relatively large code if performed on the library level.
  Therefore, compiler needs to know the value of the parameter in the compile time. That is why this parameter needs to be a constant, and not a variable.
• For PIC18F K42 and K83 family the I²C speed is fixed to 100 kHz and pins used for the I²C should be set as open-drain in ODCONx register, please consult the appropriate datasheet.
• I²C routines require you to specify the module you want to use. To select the desired I²C, simply change the letter x in the prototype for a number from 1 to 2.
• Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

Library requires MSSP module.

I2C1_Init(100000);

If there is no error, function returns 0.

Determines if I²C bus is free and issues START signal.

  Note :

• I²C routines require you to specify the module you want to use. To select the desired I²C, simply change the letter x in the prototype for a number from 1 to 2.
• Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

I²C must be configured before using this function. See I2Cx_Init.

I2C1_Start();

Nothing.

Issues repeated START signal.

  Note :

• I²C routines require you to specify the module you want to use. To select the desired I²C, simply change the letter x in the prototype for a number from 1 to 2.
• Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

I²C must be configured before using this function. See I2Cx_Init.

I2C1_Repeated_Start();

Returns 1 if I²C bus is free, otherwise returns 0.

Tests if I²C bus is free.

  Note :

• I²C routines require you to specify the module you want to use. To select the desired I²C, simply change the letter x in the prototype for a number from 1 to 2.
• Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

I²C must be configured before using this function. See I2Cx_Init.

if (I2C1_Is_Idle()) {...}

Returns one byte from the slave.

I²C must be configured before using this function. See I2Cx_Init.

Also, START signal needs to be issued in order to use this function. See I2Cx_Start (not valid for PIC18F K42 and K83 family).

Read data and send not acknowledge signal:

unsigned short take;
...
take = I2C1_Rd(0);

Returns 0 if there were no errors.

I²C must be configured before using this function. See I2Cx_Init.

Also, START signal needs to be issued in order to use this function. See I2Cx_Start (not valid for PIC18F K42 and K83 family).

I2C1_Write(0xA3);

Nothing.

Issues STOP signal.

  Note :

• I²C routines require you to specify the module you want to use. To select the desired I²C, simply change the letter x in the prototype for a number from 1 to 2.
• Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

I²C must be configured before using this function. See I2Cx_Init.

I2C1_Stop();

Nothing.

This function checks for a I²C timeout condition in a user defined time period, after which it jumps to a callback function if this condition is met.
Different I²C operations can cause a timeout (read, write, start and repeated start) so user may test which one caused it, as in the example below.

• timeout: Represents a number of while loops in which the I²C timeout condition is checked.
  Depending on the architecture (PIC16, PIC16ENH or PIC18) the generated code (i.e. the execution time) may vary for the same value of this parameter.


• i2c_timeout: pointer to the callback function. Callback function must be written according to this function prototype :

  void I2C1_TimeoutCallback(char errorCode) {
  
  }	
  

• I²C must be configured before using this function. See I2Cx_Init.
• I²C routines require you to specify the module you want to use. To select the desired I²C, simply change the letter x in the prototype for a number from 1 to 2.
• Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

// define callback function
void I2C1_TimeoutCallback(char errorCode) {

   if (errorCode == _I2C_TIMEOUT_RD) {
     // do something if timeout is caused during read
   }
   
   if (errorCode == _I2C_TIMEOUT_WR) {
     // do something if timeout is caused during write
   }
   
   if (errorCode == _I2C_TIMEOUT_START) {
     // do something if timeout is caused during start
   } 
   
   if (errorCode == _I2C_TIMEOUT_REPEATED_START) {
     // do something if timeout is caused during repeated start            
   }
}	

// initialize I2C module
I2C1_Init(100000);

// set timeout period and callback function
I2C1_SetTimeoutCallback(1000, I2C1_TimeoutCallback);

Sets the active I²C module which will be used by the I²C routines.

• start_ptr: I2Cx_Start handler
• restart_ptr: I2Cx_Repeated_Start handler
• read_ptr: I2Cx_Rd handler
• write_ptr: I2Cx_Wr handler
• stop_ptr: I2Cx_Stop handler
• is_idle_ptr: I2Cx_Is_Idle handler

Nothing.

• I²C must be configured before using this function. See I2Cx_Init.

I2C_Set_Active(&I2C1_Start, &I2C1_Repeated_Start, &I2C1_Wr, &I2C1_Wr, &I2C1_Stop, &I2C1_Is_Idle); // Sets the I2C1 module active

Number of I²C modules per MCU differs from chip to chip. Please, read the appropriate datasheet before utilizing this library.

If there is no error, function returns 0.

Determines if I²C bus is free and issues START signal.

This is a generic routine which uses the active I²C module previously activated by the I2C_Set_Active routine.

I²C must be configured before using this function. See I2Cx_Init.

I2C_Start();

Nothing.

Issues repeated START signal.

This is a generic routine which uses the active I²C module previously activated by the I2C_Set_Active routine.

I²C must be configured before using this function. See I2Cx_Init.

I2C_Restart();

Returns 1 if I²C bus is free, otherwise returns 0.

Tests if I²C bus is free.

This is a generic routine which uses the active I²C module previously activated by the I2C_Set_Active routine.

I²C must be configured before using this function. See I2Cx_Init.

if (I2C_Is_Idle()) {...}

Returns one byte from the slave.

I²C must be configured before using this function. See I2Cx_Init.

Also, START signal needs to be issued in order to use this function. See I2C_Start (not valid for PIC18F K42 and K83 family).

Read data and send not acknowledge signal:

unsigned char take;
...
I2C_Set_Active(&I2C1_Start, &I2C1_Restart, &I2C1_Read, &I2C1_Write, &I2C1_Stop, &I2C1_Is_Idle); // Sets the I2C1 module active

// Read data and send the not_acknowledge signal
take = I2C_Read(_I2C_NACK);

Returns 0 if there were no errors.

I²C must be configured before using this function. See I2Cx_Init.

Also, START signal needs to be issued in order to use this function. See I2C_Start (not valid for PIC18F K42 and K83 family).

unsigned char data_;
unsigned error
...

I2C_Set_Active(&I2C1_Start, &I2C1_Restart, &I2C1_Read, &I2C1_Write, &I2C1_Stop, &I2C1_Is_Idle); // Sets the I2C1 module active

error = I2C_Write(data_);
error = I2C_Write(0xA3);

Nothing.

Issues STOP signal.

This is a generic routine which uses the active I²C module previously activated by the I2C_Set_Active routine.

I²C must be configured before using this function. See I2Cx_Init.

I2C_Set_Active(&I2C1_Start, &I2C1_Restart, &I2C1_Read, &I2C1_Write, &I2C1_Stop, &I2C1_Is_Idle); // Sets the I2C1 module active
// Issue STOP signal
I2C_Stop();

None.