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xiic_low_level_eeprom_example.c File Reference

Overview

This file consists of a polled mode design example which uses the Xilinx IIC device and low-level driver to exercise the EEPROM.

This example writes/reads from the lower 256 bytes of the IIC EEPROMS. Please refer to the datasheets of the IIC EEPROM's for details about the internal addressing and page size of these devices.

The XIic_Send() API is used to transmit the data and XIic_Recv() API is used to receive the data.

This example is tested on ML300/ML310/ML403/ML501/ML507/ML510/ML605/SP601 and SP605 Xilinx boards.

The ML310/ML410/ML510/SCU35 boards have a on-board 64 Kb serial IIC EEPROM (Microchip 24LC64A). The WP pin of the IIC EEPROM is hardwired to ground on this board.

The ML300 board has an on-board 32 Kb serial IIC EEPROM(Microchip 24LC32A). The WP pin of the IIC EEPROM has to be connected to ground for this example. The WP is connected to pin Y3 of the FPGA.

The ML403 board has an on-board 4 Kb serial IIC EEPROM(Microchip 24LC04A). The WP pin of the IIC EEPROM is hardwired to ground on this board.

The ML501/ML505/ML507/ML605/SP601/SP605 boards have an on-board 8 Kb serial IIC EEPROM(STM M24C08). The WP pin of the IIC EEPROM is hardwired to ground on these boards.

The AddressType for ML300/ML310/ML410/ML510/SCU200/SCU35 boards should be u16 as the address pointer in the on board EEPROM is 2 bytes.

The AddressType for ML403/ML501/ML505/ML507/ML605/SP601/SP605 boards should be u8 as the address pointer for the on board EEPROM is 1 byte.

The 7 bit IIC Slave address of the IIC EEPROM on the ML300/ML310/ML403/ML410/ ML501/ML505/ML507/ML510/SCU200 boards is 0x50. The 7 bit IIC Slave address of the IIC EEPROM on the ML605/SP601/SP605 boards is 0x54. Refer to the User Guide's of the respective boards for further information about the IIC slave address of IIC EEPROM's.

The define EEPROM_ADDRESS in this file needs to be changed depending on the board on which this example is to be run.

This code assumes that no Operating System is being used.

Note
None
MODIFICATION HISTORY:
Ver     Who  Date        Changes






1.00a jhl  09/10/03 Created
1.00a sv   05/09/05 Minor changes to comply to Doxygen and coding guidelines
1.00a mta  03/09/06 Minor updates due to changes in the low level driver for
              supporting repeated start functionality.
2.00a sdm  09/22/09 Converted all register accesses to 32 bit access and minor
              modifications as per coding guidelines.
2.01a ktn  03/17/10 Updated the information about the EEPROM's used on
              ML605/SP601/SP605 boards. Updated the example so that it
              can be used to access the entire IIC EEPROM for devices
              like M24C04/M24C08 that use LSB bits of the IIC device
              select code (IIC slave address) to specify the higher
              address bits of the EEPROM internal address.
2.01a sdm  06/13/11 Updated the example to flush the Tx FIFO when waiting for
              the previous command to be completed for CR612546.
3.4   ms   01/23/17 Added xil_printf statement in main function to
                    ensure that "Successfully ran" and "Failed" strings
                    are available in all examples. This is a fix for
                    CR-965028.
3.5   sd   08/29/18 Update the fifo flush.
3.10  gm   07/09/23 Added SDT support.
3.15  vlt  03/20/26 Updated comments lines for SCU200 and SCU35 EEPROM address,
                    page size, and address type.
 
#include "xparameters.h"

#include "xiic.h"

#include "xil_io.h"

#include "xil_printf.h"





Macros


#define IIC_BASE_ADDRESS   XPAR_AXI_IIC_0_BASEADDR


 The following constants map to the XPAR parameters created in the xparameters.h file.  More...


 


#define EEPROM_ADDRESS   0x54	 /* 0xA0 as an 8 bit number */


 The following constant defines the address of the IIC Slave device on the IIC bus.  More...


 


#define PAGE_SIZE   16


 The page size determines how much data should be written at a time.  More...


 


#define EEPROM_TEST_START_ADDRESS   128


 The Starting address in the IIC EEPROM on which this test is performed.  More...


 


#define MAX_DELAY_CNT   10000


 Maximum delay count used for timeout handling.  More...


 





Typedefs


typedef u8 AddressType


 The AddressType for ML300/ML310/ML510/SCU200/SCU35 boards should be u16 as the address pointer in the on board EEPROM is 2 bytes.  More...


 





Functions


int IicLowLevelEeprom (void)


 The function uses the low level driver of IIC to read and write to the IIC EEPROM board.  More...


 


int ReadWriteVerify (AddressType Address)


 This function writes, reads, and verifies the read to the IIC EEPROM.  More...


 


unsigned EepromWriteByte (AddressType Address, u8 *BufferPtr, u16 ByteCount)


 This function writes a buffer of bytes to the IIC serial EEPROM.  More...


 


unsigned EepromReadByte (AddressType Address, u8 *BufferPtr, u16 ByteCount)


 This function reads a number of bytes from the IIC serial EEPROM into a specified buffer.  More...


 


int main (void)


 Variable for storing Eeprom IIC address.  More...


 





Variables


u8 WriteBuffer [PAGE_SIZE]


 The Error Count.  More...


 


u8 ReadBuffer [PAGE_SIZE]


 Write buffer for writing a page.  More...


 


u8 ReadBufferAll [PAGE_SIZE *4]


 Read buffer for reading a page.  More...


 


u8 EepromIicAddr


 Buffer used for reading all the data.  More...


 




Macro Definition Documentation






      

        

          #define EEPROM_ADDRESS   0x54	 /* 0xA0 as an 8 bit number */
        

      





The following constant defines the address of the IIC Slave device on the IIC bus. 


Note that since the address is only 7 bits, this constant is the address divided by 2. The 7 bit IIC Slave address of the IIC EEPROM on the ML300/ML310/ML403/ML410/ ML501/ML505/ML507/ML510/SCU200 boards is 0x50. The 7 bit IIC Slave address of the IIC EEPROM on the ML605/SP601/SP605 boards is 0x54. Please refer the User Guide's of the respective boards for further information about the IIC slave address of IIC EEPROM's. 



Referenced by IicLowLevelEeprom().











      

        

          #define EEPROM_TEST_START_ADDRESS   128
        

      





The Starting address in the IIC EEPROM on which this test is performed. 



Referenced by EepromWriteByte(), and IicLowLevelEeprom().











      

        

          #define IIC_BASE_ADDRESS   XPAR_AXI_IIC_0_BASEADDR
        

      





The following constants map to the XPAR parameters created in the xparameters.h file. 


They are defined here such that a user can easily change all the needed parameters in one place. 



Referenced by EepromReadByte(), and EepromWriteByte().











      

        

          #define MAX_DELAY_CNT   10000
        

      





Maximum delay count used for timeout handling. 



Referenced by EepromReadByte(), and EepromWriteByte().











      

        

          #define PAGE_SIZE   16
        

      





The page size determines how much data should be written at a time. 


The ML300 board supports a page size of 32 and 16 The write function should be called with this as a maximum byte count. 



Referenced by EepromWriteByte(), IicLowLevelEeprom(), and ReadWriteVerify().







Typedef Documentation






      

        

          typedef u8 AddressType
        

      





The AddressType for ML300/ML310/ML510/SCU200/SCU35 boards should be u16 as the address pointer in the on board EEPROM is 2 bytes. 


The AddressType for ML403/ML501/ML505/ML507/ML605/SP601/SP605 boards should be u8 as the address pointer in the on board EEPROM is 1 bytes. 







Function Documentation






      

        

          unsigned EepromReadByte 
          (
          AddressType 
          Address, 
        

        

          
          
          u8 * 
          BufferPtr, 
        

        

          
          
          u16 
          ByteCount 
        

        

          
          )
          
        

      





This function reads a number of bytes from the IIC serial EEPROM into a specified buffer. 


Parameters

  

    
Addresscontains the address in the EEPROM to read from. 

    
BufferPtrcontains the address of the data buffer to be filled. 

    
ByteCountcontains the number of bytes in the buffer to be read. This value is not constrained by the page size of the device such that up to 64K may be read in one call.

  

  




Returns
The number of bytes read. A value less than the specified input value indicates an error.


Note
None. 



References EepromIicAddr, IIC_BASE_ADDRESS, MAX_DELAY_CNT, XIIC_CR_ENABLE_DEVICE_MASK, XIIC_CR_REG_OFFSET, XIIC_CR_TX_FIFO_RESET_MASK, XIic_ReadReg, XIic_Recv(), XIic_Send(), XIIC_SR_BUS_BUSY_MASK, XIIC_SR_REG_OFFSET, XIIC_STOP, and XIic_WriteReg.











      

        

          unsigned EepromWriteByte 
          (
          AddressType 
          Address, 
        

        

          
          
          u8 * 
          BufferPtr, 
        

        

          
          
          u16 
          ByteCount 
        

        

          
          )
          
        

      





This function writes a buffer of bytes to the IIC serial EEPROM. 


Parameters

  

    
Addresscontains the address in the EEPROM to write to. 

    
BufferPtrcontains the address of the data to write. 

    
ByteCountcontains the number of bytes in the buffer to be written. Note that this should not exceed the page size of the EEPROM as noted by the constant PAGE_SIZE.

  

  




Returns
The number of bytes written, a value less than that which was specified as an input indicates an error.


Note
None. 



References EEPROM_TEST_START_ADDRESS, EepromIicAddr, IIC_BASE_ADDRESS, MAX_DELAY_CNT, PAGE_SIZE, WriteBuffer, XIIC_CR_ENABLE_DEVICE_MASK, XIIC_CR_REG_OFFSET, XIIC_CR_TX_FIFO_RESET_MASK, XIic_ReadReg, XIic_Send(), XIIC_STOP, and XIic_WriteReg.











      

        

          int IicLowLevelEeprom 
          (
          void 
          )
          
        

      





The function uses the low level driver of IIC to read and write to the IIC EEPROM board. 


The addresses tested are from 128 to 192.


Returns
XST_SUCCESS if successful, XST_FAILURE if unsuccessful.


Note
None. 



References EEPROM_ADDRESS, EEPROM_TEST_START_ADDRESS, EepromIicAddr, EepromReadByte(), PAGE_SIZE, ReadBufferAll, and ReadWriteVerify().



Referenced by main().











      

        

          int main 
          (
          void 
          )
          
        

      





Variable for storing Eeprom IIC address. 


Main function to call the low level EEPROM example.


Returns
XST_SUCCESS if successful, XST_FAILURE if unsuccessful.


Note
None. 



References IicLowLevelEeprom().











      

        

          int ReadWriteVerify 
          (
          AddressType 
          Address)
          
        

      





This function writes, reads, and verifies the read to the IIC EEPROM. 


It does the write as a single page write, performs a buffered read, and also performs byte reads.


Parameters

  

    
Addressis the starting address of the page in the EEPROM device to which the data is to be written.

  

  




Returns
XST_FAILURE if the test fails, XST_SUCCESS if the test passes.


Note
None. 



References EepromReadByte(), EepromWriteByte(), PAGE_SIZE, and WriteBuffer.



Referenced by IicLowLevelEeprom().







Variable Documentation






      

        

          u8 EepromIicAddr
        

      





Buffer used for reading all the data. 











      

        

          u8 ReadBuffer[PAGE_SIZE]
        

      





Write buffer for writing a page. 











      

        

          u8 ReadBufferAll[PAGE_SIZE *4]
        

      





Read buffer for reading a page. 



Referenced by IicLowLevelEeprom().











      

        

          u8 WriteBuffer[PAGE_SIZE]
        

      





The Error Count.