Flash.c File Reference

FX3 I2C EEPROM (model m24m02-dr) interfacing module. More...

#include "Flash.h"

Functions
static uint16_t	GetFlashDeviceAddress (uint32_t ByteAddress)
	Gets the flash devices address, based on the requested byte address. More...
static CyU3PReturnStatus_t	FlashTransfer (uint32_t Address, uint16_t NumBytes, uint8_t *Buf, CyBool_t isRead)
	Performs a transfer from the I2C flash memory. More...
CyU3PReturnStatus_t	AdiFlashInit ()
	Initializes flash memory interface module. More...
void	AdiFlashDeInit ()
	De-init the flash memory interfacing module. More...
void	AdiFlashWrite (uint32_t Address, uint16_t NumBytes, uint8_t *WriteBuf)
	Write a block of memory to flash, at the specified byte address. More...
void	AdiFlashRead (uint32_t Address, uint16_t NumBytes, uint8_t *ReadBuf)
	Read a block of memory from flash, at the specified byte address. More...
void	AdiFlashReadHandler (uint32_t Address, uint16_t NumBytes)
	Handles flash read requests from control endpoint. More...

Variables
uint8_t	USBBuffer [4096]
BoardState	FX3State
static CyU3PDmaChannel	flashTxHandle
static CyU3PDmaChannel	flashRxHandle

Detailed Description

FX3 I2C EEPROM (model m24m02-dr) interfacing module.

Copyright (c) 2018-2020 Analog Devices, Inc. All Rights Reserved. This software is proprietary to Analog Devices, Inc. and its licensors.

THIS SOFTWARE UTILIZES LIBRARIES DEVELOPED AND MAINTAINED BY CYPRESS INC. THE LICENSE INCLUDED IN THIS REPOSITORY DOES NOT EXTEND TO CYPRESS PROPERTY.

Use of this file is governed by the license agreement included in this repository.

Date

04/30/2020

Author

A. Nolan (alex..nosp@m.nola.nosp@m.n@ana.nosp@m.log..nosp@m.com)

Function Documentation

AdiFlashDeInit()

void AdiFlashDeInit

(

)

De-init the flash memory interfacing module.

Returns

void

This functions destroys the DMA channels used for interfacing with the I2C module, and re-inits the I2C controller to operate in register mode, with the previously selected bitrate.

AdiFlashInit()

CyU3PReturnStatus_t AdiFlashInit

(

)

Initializes flash memory interface module.

Returns

Status code indication the success of the flash init operation

The FX3 board features a ST m24m02-dr I2C EEPROM. This function initializes the FX3 I2C block to operate in DMA mode with the max supported I2C clock. It then configures the I2C Rx and Tx channels to perform a transfer

AdiFlashRead()

void AdiFlashRead	(	uint32_t	Address,
		uint16_t	NumBytes,
		uint8_t *	ReadBuf
	)

Read a block of memory from flash, at the specified byte address.

Parameters

Address	The start address (in flash) to perform the read operation from
NumBytes	The number of bytes to read from the flash
ReadBuf	RAM buffer to read flash data into

Returns

void

This function leaves the I2C EEPROM write functionality disabled. This prevents inadvertent writes from being processed.

AdiFlashReadHandler()

void AdiFlashReadHandler	(	uint32_t	Address,
		uint16_t	NumBytes
	)

Handles flash read requests from control endpoint.

Parameters

Address	The byte address in flash to start reading at
NumBytes	The number of bytes to read. Max 4KB

Returns

void

The data read from flash is returned over the control endpoint. This limits a single read to 4KB. If greater than a 4KB read is needed, multiple transactions should be sent. Managing this limit is left to the higher level software sending USB commands.

AdiFlashWrite()

void AdiFlashWrite	(	uint32_t	Address,
		uint16_t	NumBytes,
		uint8_t *	WriteBuf
	)

Write a block of memory to flash, at the specified byte address.

Parameters

Address	The start address (in flash) to perform the write operation to
NumBytes	The number of bytes to write to flash
WriteBuf	RAM buffer containing data to be written to flash

Returns

void

This function controls the flash write enable signal. This write enable signal is used to prevent un-intended writes the flash from user space, via I2C functions. This write enable signal is only present on the iSensor FX3 board rev C or newer, but there shouldn't be any downside to asserting it on older hardware models.

FlashTransfer()

static CyU3PReturnStatus_t FlashTransfer ( uint32_t  Address, uint16_t  NumBytes, uint8_t *  Buf, CyBool_t  isRead  )

static

Performs a transfer from the I2C flash memory.

Parameters

Address	The flash byte address to start the read/write operation from. Valid range 0x0 - 0x40000
NumBytes	The number of data bytes to transfer to/from the flash
Buf	RAM data buffer. Write data must be placed here. Read data is returned here.
isRead	Bool indicating if operation is read or write

Returns

Status code indicating the success of the flash read/write operation

This function performs all interfacing with the ST m24m02-dr I2C EEPROM which is included on the iSensor FX3 board (and FX3 explorer kit). Before each transaction, AdiFlashInit is called to ensure the flash and DMA are configured properly. Then, for each transaction, the read/write is split into 64 byte (or less) chunks, which are each performed using a single I2C<->Mem DMA transfer. Once all required transfers have been performed, the flash is de-initialized.

GetFlashDeviceAddress()

static uint16_t GetFlashDeviceAddress ( uint32_t  ByteAddress )

static

Gets the flash devices address, based on the requested byte address.

Returns

void The 8-bit flash device address

For the EEPROM, byte address bits 16-17 are encoded into the device address

Variable Documentation

flashRxHandle

CyU3PDmaChannel flashRxHandle

static

I2C Rx DMA channel handle

flashTxHandle

CyU3PDmaChannel flashTxHandle

static

I2C Tx DMA channel handle

FX3State

BoardState FX3State

extern

FX3 state (from main)

Struct. which stores all run time configurable FX3 settings

USBBuffer

uint8_t USBBuffer[4096]

extern

Global USB Buffer, from main