/******************** (C) COPYRIGHT 2003 STMicroelectronics ******************** * File Name : i2c.c * Author : MCD Application Team * Date First Issued : 09/05/2003 * Description : This file provides Code sources I2C functions ******************************************************************************** * History: * 24/05/2005 : V3.0 * 30/11/2004 : V2.0 * 14/07/2004 : V1.3 * 01/01/2004 : V1.2 ******************************************************************************* THE PRESENT SOFTWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS. *******************************************************************************/ #include "i2c.h" #include "rccu.h" #include /******************************************************************************* * Function Name : I2C_Init * Description : Initializes I2C peripheral control and registers to their * default reset values. * Input : I2Cx ( I2C0 or I2C1 ) * Return : None. *******************************************************************************/ void I2C_Init (I2C_TypeDef *I2Cx) { //Initialize all the register of the specified I2C passed as parameter I2Cx->CR=0x0; I2Cx->CCR=0x0; I2Cx->ECCR=0x0; I2Cx->OAR1=0x0; I2Cx->OAR2=0x0; (void)I2Cx->SR1; (void)I2Cx->SR2; I2Cx->DR=0x0; } /******************************************************************************* * Function Name : I2C_OnOffConfig * Description : Enables or disables I2C peripheral. * Input : I2Cx ( I2C0 or I2C1 ) * condition(ENABLE or DISABLE). * Return : None. *******************************************************************************/ void I2C_OnOffConfig (I2C_TypeDef *I2Cx, FunctionalState NewState) { if (NewState == ENABLE) { // Enable the I2C selected by setting twice the PE bit on the CR register I2Cx->CR |= I2C_PESET_Mask; I2Cx->CR |= I2C_PESET_Mask; } else // Disable the I2C selected I2Cx->CR &= ~I2C_PESET_Mask; } /******************************************************************************* * Function Name : I2C_FlagStatus * Description : Checks whether any I2C Flag is set or not. * Input : I2Cx ( I2C0 or I2C1 ) * Access(DIRECT or INDIRECT) * Flag : the flag to be read * input 4: an (u8) variable needed in the case * of the INDIRECT access * Return : the NewState of the Flag (SET or RESET). *******************************************************************************/ FlagStatus I2C_FlagStatus (I2C_TypeDef *I2Cx, RegisterAccess Access, I2C_Flags Flag, ...) { u32 Tmp; if (Access == DIRECT) // Store in Tmp variable the register where is located the flag Tmp = I2C_GetStatus(I2Cx)&Flag; else { va_list list; //Get the fourth register va_start(list,Flag); Tmp = va_arg(list,u32); Tmp&=Flag; } //Return the Flag NewState return Tmp != 0 ? SET : RESET; } /******************************************************************************* * Function Name : I2C_FlagClear * Description : Clears the I2C Flag passed as a parameter * Input : I2Cx ( I2C0 or I2C1 ) * Flag : the flag to be read * input3: an (u8) parameter needed in the case that the flag * to be cleared need a write in one register * Return : None. *******************************************************************************/ void I2C_FlagClear (I2C_TypeDef *I2Cx, I2C_Flags Flag, ...) { u8 Tmp = (u8)*((u32 *)&Flag + sizeof(Flag)); if (Flag==I2C_ADD10 || Flag==I2C_EVF || Flag==I2C_BERR || Flag==I2C_ARLO || Flag==I2C_STOPF || Flag==I2C_AF || Flag==I2C_ENDAD) //flags that need a read of the SR2 register to be cleared { // Read the SR2 register (void)I2Cx->SR2; // Two flags need a second step to be cleared switch (Flag) { case I2C_ADD10: I2Cx->DR = Tmp; break; case I2C_ENDAD: I2Cx->CR|=0x20; break; } } else if (Flag==I2C_SB || Flag==I2C_ADSL || Flag==I2C_BTF || Flag==I2C_TRA) //flags that need a read of the SR1 register to be cleared { // Read the SR1 register (void)I2Cx->SR1; if (Flag==I2C_SB) I2Cx->DR=Tmp; else if (Flag==I2C_BTF || Flag==I2C_TRA) (void)I2Cx->DR; } else if ( Flag==I2C_M_SL || Flag==I2C_GCAL) //flags that need the PE bit to be cleared { I2C_OnOffConfig (I2Cx, DISABLE); I2C_OnOffConfig (I2Cx, ENABLE); } } /******************************************************************************* * Function Name : I2C_SpeedConfig * Description : Selects I2C clock speed and configures its corresponding mode. * Input : I2Cx ( I2C0 or I2C1 ) * Clock: I2C expected clock in Hertz. * Return : None. *******************************************************************************/ void I2C_SpeedConfig (I2C_TypeDef *I2Cx, u32 Clock) { u32 FCLK; u16 result; // Get the FCLK frequency using the RCCU library FCLK = RCCU_FrequencyValue ( RCCU_FCLK ); // Test on speed mode // Update the CCR and ECCR are updated if (Clock <=100000) // Standard mode selected { result = ((FCLK / Clock) - 7)/2; //Clear FM/SM bit I2Cx->CCR=result &0x7f; } else if (Clock <=400000) { // Fast mode selected result = ((FCLK/Clock)-9)/3; //set FM/SM bit I2Cx->CCR=result |0x80; } I2Cx->ECCR= result >>7; } /******************************************************************************* * Function Name : I2C_AddressConfig * Description : Defines the I2C bus address of the interface. * Input : I2Cx ( I2C0 or I2C1 ). * Address: an u16 parameter indicating the address * of the interface. * Mode (I2C_Mode10,I2C_Mode7). * Return : None. *******************************************************************************/ void I2C_AddressConfig (I2C_TypeDef *I2Cx, u16 Address, I2C_Addressing Mode) { //Update OAR1 bit[7:1] by the lowest byte of address I2Cx->OAR1 = (u8)Address; if (Mode == I2C_Mode10) //Update Add8 and add9 bits in OAR2 I2Cx->OAR2 |= (Address & 0x0300)>>7; } /******************************************************************************* * Function Name : I2C_FCLKConfig * Description : Configures frequency bits according to RCLK frequency. * the selected I2C must be disabled * Input : I2Cx ( I2C0 or I2C1 ) * Return : None. *******************************************************************************/ void I2C_FCLKConfig (I2C_TypeDef *I2Cx) { u32 FCLK; // Get the FCLK frequency using the RCCU library FCLK = RCCU_FrequencyValue ( RCCU_FCLK ); // Test the value of the FCLK and affect FR0,FR1&FR2 of the OAR2 register if (FCLK > 5000000) { if (FCLK <10000000) I2Cx->OAR2 |= 0x00; else if (FCLK <16670000) I2Cx->OAR2 |= 0x20; else if (FCLK < 26670000) I2Cx->OAR2 |= 0x40; else if (FCLK <40000000) I2Cx->OAR2 |= 0x60; else if (FCLK < 53330000) I2Cx->OAR2 |= 0x80; else if (FCLK < 66000000) I2Cx->OAR2 |= 0xA0; else if (FCLK <80000000) I2Cx->OAR2 |= 0xC0; else if (FCLK <100000000) I2Cx->OAR2 |= 0xE0; } } /******************************************************************************* * Function Name : I2C_AddressSend * Description : Transmits the address byte to select the slave device. * Input : I2Cx ( I2C0 or I2C1 ) * Address: an u16 parameter indicating the slave address * Mode (I2C_Mode10,I2C_Mode7). * Direction (I2C_RX,I2C_TX). * Return : None. ********************************************************************************/ void I2C_AddressSend (I2C_TypeDef *I2Cx, u16 Address, I2C_Addressing Mode, I2C_Direction Direction) { if (Mode == I2C_Mode10 ) //10 bit addressing mode { // Update the DR register by generated header I2Cx->DR = ((Address>>7)|0xf0)&0xfe; //Wait till I2C_ADD10 flag is set while ((I2Cx->SR1&0x40)==0); //clear I2C_ADD10 flag (void)I2Cx->SR2; I2Cx->DR=(u8)Address; //Test on the direction to define the read/write bit if (Direction == I2C_RX) { //Wait till I2C_ENDAD flag is set while ((I2Cx->SR2&0x20)==0); I2Cx->CR|=0x20; //Repeated START Generate I2C_STARTGenerate (I2Cx, ENABLE); //Test on SB flag status while ((I2Cx->SR1&0x01)==0); I2Cx->DR = ((Address>>7)|0xf1); } } else // 7 bit addressing mode { if (Direction == I2C_RX) Address|=0x01; else Address&=~0x01; I2Cx->DR=(u8)Address; } } /******************************************************************************* * Function Name : I2C_ByteSend * Description : Send a single byte of data. * Input : I2Cx ( I2C0 or I2C1 ) * Data : the byte to be sent to the slave * Return : None. *******************************************************************************/ void I2C_ByteSend (I2C_TypeDef *I2Cx, u8 Data) { //Write in the DR register the byte to be sent I2Cx->DR = Data; } /******************************************************************************* * Function Name : I2C_BufferSend * Description : Send data from a buffer whose number of bytes is known * Input : I2Cx ( I2C0 or I2C1 ) * PtrToBuffer :pointer to the byte of buffer to be transmitted. * NbOfBytes:Number of byte of the buffer * Return : I2C_Tx_Status :transmission status (I2C_TX_AF, I2C_TX_ARLO, * I2C_TX_BERR,I2C_TX_DATA_OK) *******************************************************************************/ I2C_Tx_Status I2C_BufferSend (I2C_TypeDef *I2Cx, u8 *PtrToBuffer, u8 NbOfBytes) { u8 Interruption_Status; u8 SentBytes; u8 error; I2C_Tx_Status I2C_TXTMP; //Test of the interrupt status Interruption_Status=0; Interruption_Status=I2Cx->CR & 0x01; I2C_ITConfig (I2Cx, DISABLE); //Wait till I2C_BTF bit is set while ((I2Cx->SR1 & 0x08 )==0); SentBytes=0; while (SentBytesDR= *(PtrToBuffer+SentBytes); //Wait till I2C_BTF bit is set or error detected do error = I2Cx->SR2 & 0x16; while ((I2Cx->SR1 & 0x08)==0 && error==0); // In case of error exit if (error) break; // increment SentBytes counter SentBytes++; } if (error) { if (error & 0x10) // I2C_TX_AF if Acknowledge failure is detected I2C_TXTMP = I2C_TX_AF; if (error & 0x02) //I2C_TX_ARLO if the ARLO bit is set in the SR2 register I2C_TXTMP = I2C_TX_ARLO; if (error & 0x04) // I2C_TX_BERR if the BERR bit is set in the SR2 register I2C_TXTMP= I2C_TX_BERR; } else //I2C_TX_DATA_OK to show that the buffer is well sent I2C_TXTMP= I2C_TX_DATA_OK; //Restore the interrupt status if (Interruption_Status==1) I2C_ITConfig (I2Cx, ENABLE); return I2C_TXTMP; } /******************************************************************************* * Function Name : I2C_StringSend * Description : Send data from a buffer * Input : I2Cx ( I2C0 or I2C1 ) * PtrToBuffer :pointer to the byte of string to be transmitted. * Return : I2C_Tx_Status :transmission status (I2C_TX_AF, I2C_TX_ARLO, * I2C_TX_BERR,I2C_TX_DATA_OK) *******************************************************************************/ I2C_Tx_Status I2C_StringSend (I2C_TypeDef *I2Cx, char *PtrToString) { u8 NbOfBytes=0; // count the number of byte composing the string passed as parameter. while (*(PtrToString+NbOfBytes)!= '\0') NbOfBytes++; // call I2C_BufferSend function to execute the send part return I2C_BufferSend (I2Cx,(u8 *)PtrToString,NbOfBytes); } /******************************************************************************* * Function Name : I2C_TransmissionStatus * Description : Report the NewState of the transmission * Input : I2Cx ( I2C0 or I2C1 ) * Return : I2C_Tx_Status :transmission status (I2C_TX_NO, I2C_TX_SB, * I2C_TX_AF, I2C_TX_ARLO, I2C_TX_BERR,I2C_TX_ADD_OK, * I2C_TX_DATA_OK,I2C_TX_ONGOING) *******************************************************************************/ I2C_Tx_Status I2C_TransmissionStatus (I2C_TypeDef *I2Cx) { u8 SR1value; u8 SR2value; I2C_Tx_Status NewState; SR1value = I2Cx->SR1; SR2value = I2Cx->SR2; if ((I2Cx->SR1&0x10)==0) NewState=I2C_TX_NO; else if (I2Cx->SR1&0x01) //I2C_SB bit is set NewState=I2C_TX_SB; else if ((SR2value & 0x10)&&(I2Cx->CR&0x04)) //I2C_ACK &I2C_AF are both set NewState=I2C_TX_AF; else if (SR2value & 0x04) //I2C_ARLO is set in multimaster mode NewState=I2C_TX_ARLO; else if (SR2value & 0x02) //I2C_BERR bit is set NewState=I2C_TX_BERR; else if ((SR1value & 0x80)&& (I2Cx->SR2&0x20)) //I2C_EVF and I2C_ENDAD are both set NewState=I2C_TX_ADD_OK; else if ((I2Cx->SR1&0x20)&& (I2Cx->SR1&0x08)) //I2C_TRA and I2C_BTF are both set NewState=I2C_TX_DATA_OK; else NewState=I2C_TX_ONGOING; return NewState; } /******************************************************************************* * Function Name : I2C_ByteReceive * Description : Returns the received byte. * Input : I2Cx ( I2C0 or I2C1 ) * Return : the byte received *******************************************************************************/ u8 I2C_ByteReceive (I2C_TypeDef *I2Cx) { //Wait till I2C_BTF bit is set while ((I2Cx->SR1 & 0x08)==0); return I2Cx->DR; } /******************************************************************************* * Function Name : I2C_BufferReceive * Description : received a buffer. and return the status of error. * Input : I2Cx ( I2C0 or I2C1 ) * PtrToBuffer :pointer to the byte of buffer received. * NbOfBytes:Number of byte to be received * Return : I2C_Rx_Status:the NewState of the reception (,I2C_RX_AF, * I2C_RX_ARLO,I2C_RX_BERR, I2C_RX_DATA_OK) *******************************************************************************/ I2C_Rx_Status I2C_BufferReceive (I2C_TypeDef *I2Cx, u8 *PtrToBuffer, u8 NbOfBytes) { u8 Interruption_Status; u8 ReceivedBytes; u8 error; I2C_Rx_Status I2C_RXTMP; //Test of the interrupt status Interruption_Status=0; Interruption_Status=I2Cx->CR & 0x01; I2C_ITConfig (I2Cx, DISABLE); ReceivedBytes=0; while (ReceivedBytesSR2 & 0x16; while ((I2Cx->SR1 & 0x08)==0 && !error); if (error==0) // No error detected { *(PtrToBuffer+ReceivedBytes) = I2Cx->DR; ReceivedBytes++; } else break; } if (error) { if (error & 0x10) // I2C_RX_AF if Acknowledge failure is detected I2C_RXTMP= I2C_RX_AF; else if (error & 0x02) // I2C_RX_ARLO if the ARLO bit is set in the SR2 register I2C_RXTMP= I2C_RX_ARLO; else if (error & 0x04) // I2C_RX_BERR if the BERR bit is set in the SR2 register I2C_RXTMP= I2C_RX_BERR; } else //I2C_RX_DATA_OK to show that the buffer is well sent I2C_RXTMP= I2C_RX_DATA_OK; //Restore the interrupt status if (Interruption_Status==1) I2C_ITConfig (I2Cx, ENABLE); return I2C_RXTMP; } /******************************************************************************* * Function Name :I2C_ReceptionStatus * Description : Report the reception NewState. * Input : I2Cx ( I2C0 or I2C1 ) * Return : I2C_Rx_Status:the NewState of the reception ( I2C_RX_NO, * I2C_RX_SB,I2C_RX_AF,I2C_RX_ARLO,I2C_RX_BERR,I2C_RX_ADD_OK, * I2C_RX_DATA_OK, I2C_RX_ONGOING) *******************************************************************************/ I2C_Rx_Status I2C_ReceptionStatus (I2C_TypeDef *I2Cx) { u8 SR1value; u8 SR2value; I2C_Rx_Status NewState; SR1value= I2Cx->SR1; SR2value= I2Cx->SR2; if ((I2Cx->SR1&0x10) == 0) NewState=I2C_RX_NO; else if (I2Cx->SR1&0x01) //I2C_SB bit is set NewState=I2C_RX_SB; else if ((SR2value & 0x10) && (I2Cx->CR&0x04)) //I2C_ACK &I2C_AF are both set NewState=I2C_RX_AF; else if (SR2value & 0x04) //I2C_ARLO is set NewState=I2C_RX_ARLO; else if (SR2value & 0x02) //I2C_BERR bit is set NewState=I2C_RX_BERR; else if ((SR1value & 0x80) && (I2Cx->SR1&0x08)==0) //2C_EVF is set & I2C_BTF is not set NewState=I2C_RX_ADD_OK; else if ((I2Cx->SR1&0x20)==0 && (I2Cx->SR1&0x08)) //II2C_TRA is cleared & I2C_BTF is set NewState=I2C_RX_DATA_OK; else NewState=I2C_RX_ONGOING; return NewState; } /******************* (C) COPYRIGHT 2003 STMicroelectronics *****END OF FILE****/