xspi_eeprom_example.c File Reference

Overview

This file contains a design example using the SPI driver (XSpi) and hardware device with a serial EEPROM device.

The hardware which this example runs on must have a serial EEPROM (Microchip 25XX320 or 25XX160) for it to run. This example has been tested with the SPI EEPROM on the ML410 platform for PPC processor.

Note

None.

 MODIFICATION HISTORY:

 Ver   Who  Date     Changes



 1.00b jhl  02/27/01 First release
 1.00c jhl  08/15/03 Fixed bugs (local instances and large buffers are now
                                 moved to globals)
 1.11a sv   9/10/07  Minor changes to comply to Doxygen and coding guidelines
 3.00a ktn  10/28/09 Converted all register accesses to 32 bit access.
                      Updated to use the HAL APIs/macros. Replaced call to
                      XSpi_Initialize API with XSpi_LookupConfig and
                      XSpi_CfgInitialize.
 4.2   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.
       ms   04/05/17 Modified Comment lines to follow doxygen rules.
 4.11  sb   07/11/23 Added support for system device-tree flow.

Functions
void	SpiHandler (void *CallBackRef, u32 StatusEvent, unsigned int ByteCount)
	This function is the handler which performs processing for the SPI driver. More...
void	EepromRead (XSpi *SpiPtr, u16 Address, int ByteCount, EepromBuffer Buffer)
	This function reads from the Microchip serial EEPROM connected to the SPI interface. More...
void	EepromWrite (XSpi *SpiPtr, u16 Address, u8 ByteCount, EepromBuffer Buffer)
	This function writes to the Microchip serial EEPROM connected to the SPI interface. More...
int	main (void)
	The purpose of this function is to illustrate how to use the XSpi device driver. More...

Function Documentation

void EepromRead	(	XSpi *	SpiPtr,
		u16	Address,
		int	ByteCount,
		EepromBuffer	Buffer
	)

This function reads from the Microchip serial EEPROM connected to the SPI interface.

Parameters

SpiPtr	is a pointer to the SPI driver component to use.
Address	contains the address to read data from in the EEPROM.
ByteCount	contains the number of bytes to read.
Buffer	is a buffer to read the data into.

Returns

None.

Note

None.

References XSpi_Transfer().

Referenced by main().

void EepromWrite	(	XSpi *	SpiPtr,
		u16	Address,
		u8	ByteCount,
		EepromBuffer	Buffer
	)

This function writes to the Microchip serial EEPROM connected to the SPI interface.

This function is not designed to be a driver to handle all the conditions of the EEPROM device. The EEPROM contains a 32 byte write buffer which can be filled and then a write is automatically performed by the device. All the data put into the buffer must be in the same page of the device with page boundaries being on 32 byte boundaries.

Parameters

SpiPtr	is a pointer to the SPI driver component to use.
Address	contains the address to write data to in the EEPROM.
ByteCount	contains the number of bytes to write.
Buffer	is a buffer of data to write from.

Returns

None.

Note

None.

References XSpi_Transfer().

Referenced by main().

int main

(

void

)

The purpose of this function is to illustrate how to use the XSpi device driver.

This test writes and reads data from a Microchip serial EEPROM. This part must be present in the hardware to use this example.

Returns

XST_SUCCESS if successful else XST_FAILURE.

Note

This function calls functions which contain loops that may be infinite if interrupts are not working such that it may not return. If the device slave select is not correct and the device is not responding on bus it will read a status of 0xFF for the status register as the bus is pulled up.

References XSpi_Config::BaseAddress, EepromRead(), EepromWrite(), SpiHandler(), XSP_MASTER_OPTION, XSpi_CfgInitialize(), XSpi_InterruptHandler(), XSpi_LookupConfig(), XSpi_SetOptions(), XSpi_SetSlaveSelect(), XSpi_SetStatusHandler(), and XSpi_Start().

void SpiHandler	(	void *	CallBackRef,
		u32	StatusEvent,
		unsigned int	ByteCount
	)

This function is the handler which performs processing for the SPI driver.

It is called from an interrupt context such that the amount of processing performed should be minimized. It is called when a transfer of SPI data completes or an error occurs.

This handler provides an example of how to handle SPI interrupts but is application specific.

Parameters

CallBackRef	is a reference passed to the handler.
StatusEvent	is the status of the SPI .
ByteCount	is the number of bytes transferred.

Returns

None

Note

None.