Difference between revisions of "I2C"

 
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=I2C=
 
=I2C=
  
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==I2C_Init==
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{|{{Widget:LibCol}}
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{{#Widget:LibTable}}
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|-
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|Defination || void I2C_Init()
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|-
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| Input Arguments || none
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|-
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| Return Value|| none
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|-
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| Description ||  This function is used to initialize the I2C module.
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|-
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| Usage || I2C_Init();
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|}
  
  
 
==I2C_Start==
 
==I2C_Start==
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{| class="wikitable"  style="colspan:1; background-color:#4682B4;"
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{|{{Widget:LibCol}}
 
{{#Widget:LibTable}}
 
{{#Widget:LibTable}}
 
|-
 
|-
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|Defination ||  
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|Defination || void I2C_Start()
 
|-
 
|-
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| Input Arguments ||  
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| Input Arguments || none
 
|-
 
|-
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| Return Value||  
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| Return Value|| none
 
|-
 
|-
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| Description ||   
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| Description ||  This function is used to generate I2C Start Condition.<br />Start Condition: SDA goes low when SCL is High.
 
|-
 
|-
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| Usage ||
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| Usage || I2C_Start();
 
|}
 
|}
  
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==I2C_Stop==  
 
==I2C_Stop==  
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{|{{Widget:LibCol}}
 
{{#Widget:LibTable}}
 
{{#Widget:LibTable}}
 
|-
 
|-
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|Defination ||  
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|Defination || void I2C_Stop()
 
|-
 
|-
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| Input Arguments ||  
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| Input Arguments || none
 
|-
 
|-
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| Return Value||  
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| Return Value|| none
 
|-
 
|-
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| Description ||   
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| Description ||  This function is used to generate I2C Stop Condition.<br />Stop Condition: SDA goes High when SCL is High.
 
|-
 
|-
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| Usage ||
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| Usage || I2C_Stop();
 
|}
 
|}
  
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==I2C_Write==
 
==I2C_Write==
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{| class="wikitable"  style="colspan:1; background-color:#4682B4;"
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{|{{Widget:LibCol}}
 
{{#Widget:LibTable}}
 
{{#Widget:LibTable}}
 
|-
 
|-
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|Defination ||  
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|Defination || void I2C_Write(uint8_t var_i2cData_u8)
 
|-
 
|-
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| Input Arguments ||  
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| Input Arguments || uint8_t : 8-bit data to be transmitted.
 
|-
 
|-
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| Return Value||  
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| Return Value|| none
 
|-
 
|-
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| Description ||  
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| Description || This function is used to send a byte on SDA line using I2C protocol.<br />8bit data is sent bit-by-bit on each clock cycle.<br />MSB(bit) is sent first and LSB(bit) is sent at last.
 
|-
 
|-
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| Usage ||  
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| Usage || I2C_Write(0x05); //transmits 0x05 on I2C lines<br />I2C_Write(var_i2cData_u8); //Transmits 8bit data stored in var_i2cData_u8
 
|}
 
|}
  
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==I2C_Read==
 
==I2C_Read==
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{| class="wikitable"  style="colspan:1; background-color:#4682B4;"
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{|{{Widget:LibCol}}
 
{{#Widget:LibTable}}
 
{{#Widget:LibTable}}
 
|-
 
|-
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|Defination ||  
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|Defination || uint8_t I2C_Read(uint8_t var_ackOption_u8)
 
|-
 
|-
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| Input Arguments ||  
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| Input Arguments || uint8_t: Acknowledgement to be sent after data reception.<br />
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*1:Positive acknowledgement<br />
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*0:Negative acknowledgement
 
|-
 
|-
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| Return Value||  
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| Return Value|| uint8_t: Data received form I2C lines.
 
|-
 
|-
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| Description ||  
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| Description || This fun is used to receive a byte on SDA line using I2C protocol.
 
|-
 
|-
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| Usage ||  
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| Usage || <syntaxhighlight  lang = "c">
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void mian()
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{
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    *ptr_sec_u8 = I2C_Read(1);                // read second and return Positive ACK
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    *ptr_min_u8 = I2C_Read(1);             // read minute and return Positive ACK
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    *ptr_hour_u8 = I2C_Read(0);              // read hour and return Negative/No ACK
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}
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</syntaxhighlight>
 
|}
 
|}
  
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==User_Guide==
 
==User_Guide==
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<syntaxhighlight  lang = "c">
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/*Below examples demonstrate the usage of I2C library to read and write the RTC(DS1307) time. */
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void RTC_SetTime(uint8_t var_hour_u8, uint8_t var_min_u8, uint8_t var_sec_u8)
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{
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I2C_Start();                            // Start I2C communication
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I2C_Write(C_Ds1307WriteMode_U8);        // connect to DS1307 by sending its ID on I2c Bus
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I2C_Write(C_Ds1307SecondRegAddress_U8); // Select the SEC RAM address
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I2C_Write(var_sec_u8);               // Write sec from RAM address 00H
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I2C_Write(var_min_u8);               // Write min from RAM address 01H
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I2C_Write(var_hour_u8);               // Write hour from RAM address 02H
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I2C_Stop();                      // Stop I2C communication after Setting the Time
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}
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void RTC_GetTime(uint8_t *ptr_hour_u8,uint8_t *ptr_min_u8,uint8_t *ptr_sec_u8)
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{
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I2C_Start();                              // Start I2C communication
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I2C_Write(C_Ds1307WriteMode_U8);         // connect to DS1307 by sending its ID on I2c Bus
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I2C_Write(C_Ds1307SecondRegAddress_U8);  // Request Sec RAM address at 00H
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I2C_Stop();         // Stop I2C communication after selecting Sec Register
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I2C_Start();                 // Start I2C communication
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I2C_Write(C_Ds1307ReadMode_U8);          // connect to DS1307(Read mode) by sending its ID
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*ptr_sec_u8 = I2C_Read(1);              // read second and return Positive ACK
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*ptr_min_u8 = I2C_Read(1);         // read minute and return Positive ACK
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*ptr_hour_u8 = I2C_Read(0);              // read hour and return Negative/No ACK
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I2C_Stop();                 // Stop I2C communication after reading the Time
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}
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</syntaxhighlight>

Latest revision as of 10:48, 10 January 2015


I2C

I2C_Init

{{#Widget:LibTable}}
Defination void I2C_Init()
Input Arguments none
Return Value none
Description This function is used to initialize the I2C module.
Usage I2C_Init();


I2C_Start

{{#Widget:LibTable}}
Defination void I2C_Start()
Input Arguments none
Return Value none
Description This function is used to generate I2C Start Condition.
Start Condition: SDA goes low when SCL is High.
Usage I2C_Start();



I2C_Stop

{{#Widget:LibTable}}
Defination void I2C_Stop()
Input Arguments none
Return Value none
Description This function is used to generate I2C Stop Condition.
Stop Condition: SDA goes High when SCL is High.
Usage I2C_Stop();



I2C_Write

{{#Widget:LibTable}}
Defination void I2C_Write(uint8_t var_i2cData_u8)
Input Arguments uint8_t : 8-bit data to be transmitted.
Return Value none
Description This function is used to send a byte on SDA line using I2C protocol.
8bit data is sent bit-by-bit on each clock cycle.
MSB(bit) is sent first and LSB(bit) is sent at last.
Usage I2C_Write(0x05); //transmits 0x05 on I2C lines
I2C_Write(var_i2cData_u8); //Transmits 8bit data stored in var_i2cData_u8



I2C_Read

{{#Widget:LibTable}}
Defination uint8_t I2C_Read(uint8_t var_ackOption_u8)
Input Arguments uint8_t: Acknowledgement to be sent after data reception.
  • 1:Positive acknowledgement
  • 0:Negative acknowledgement
Return Value uint8_t: Data received form I2C lines.
Description This fun is used to receive a byte on SDA line using I2C protocol.
Usage 
void mian()
{
    *ptr_sec_u8 = I2C_Read(1);                // read second and return Positive ACK
    *ptr_min_u8 = I2C_Read(1); 	             // read minute and return Positive ACK
    *ptr_hour_u8 = I2C_Read(0);              // read hour and return Negative/No ACK
}


User_Guide

/*Below examples demonstrate the usage of I2C library to read and write the RTC(DS1307) time. */
 
void RTC_SetTime(uint8_t var_hour_u8, uint8_t var_min_u8, uint8_t var_sec_u8)
{
	I2C_Start();                            // Start I2C communication
 
	I2C_Write(C_Ds1307WriteMode_U8);        // connect to DS1307 by sending its ID on I2c Bus
	I2C_Write(C_Ds1307SecondRegAddress_U8); // Select the SEC RAM address
 
	I2C_Write(var_sec_u8);	               // Write sec from RAM address 00H
	I2C_Write(var_min_u8);	               // Write min from RAM address 01H
	I2C_Write(var_hour_u8);	               // Write hour from RAM address 02H
 
	I2C_Stop();                 	      // Stop I2C communication after Setting the Time
}
 
 
void RTC_GetTime(uint8_t *ptr_hour_u8,uint8_t *ptr_min_u8,uint8_t *ptr_sec_u8)
{
	I2C_Start();                              // Start I2C communication
 
	I2C_Write(C_Ds1307WriteMode_U8);	         // connect to DS1307 by sending its ID on I2c Bus
	I2C_Write(C_Ds1307SecondRegAddress_U8);   // Request Sec RAM address at 00H
 
	I2C_Stop();			        // Stop I2C communication after selecting Sec Register
 
	I2C_Start();		                // Start I2C communication
	I2C_Write(C_Ds1307ReadMode_U8);          // connect to DS1307(Read mode) by sending its ID
 
	*ptr_sec_u8 = I2C_Read(1);               // read second and return Positive ACK
	*ptr_min_u8 = I2C_Read(1); 	        // read minute and return Positive ACK
	*ptr_hour_u8 = I2C_Read(0);              // read hour and return Negative/No ACK
 
	I2C_Stop();		                // Stop I2C communication after reading the Time
}
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