Class M25PxxIo

java.lang.Object

cbsw.adept.xilinx.M25PxxIo

class M25PxxIo
extends Object

Programmatic interface for SPI flash memories

The IO interface addresses are set in Java Preferences:

/M25Pxx/rxBase Receive buffer address

/M25Pxx/txBase Transmit buffer address

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final byte	BE
(package private) ByteBuffer	byteBuffer
(package private) byte[]	bytes
(package private) RegisterIo	io
(package private) final int	pageSize
(package private) static final byte	PP
(package private) Preferences	prefs
(package private) static final byte	RDID
(package private) static final byte	RDSR
(package private) static final byte	READ
(package private) static final byte	SE
(package private) JTextArea	textArea
(package private) final int	txPages
(package private) static final byte	WRDI
(package private) static final byte	WREN

Constructor Summary

Constructors

Constructor	Description
M25PxxIo(RegisterIo io)	Constructor

Method Summary

Modifier and Type	Method	Description
void	append(byte code, short opLength)	Appends dataless operation to transaction buffer
void	append(byte code, short opLength, byte[] buf)	Appends operation to transaction buffer with data
(package private) void	bulkErase(boolean poll, JTextField statusTF)	Does bulk erase operation
void	clear()	Clears the transaction buffer
void	getRxBuffer(int offset, byte[] buf)	Reads data from the RX buffer
void	op(int offset, boolean waitflag)	Writes instruction to buffer.
(package private) void	pp(int start)	Does oage program operation
(package private) void	program(byte[] buf, JTextField statusTF)	Reads the flash data from file and programs flash.
(package private) void	read(int start)	Does read operation
(package private) void	read(int start, int len)	Does read operation
void	save(FileOutputStream fo, int npages)
(package private) void	sectorErase(int start)	Does sector erase operation
void	setTextArea(JTextArea textArea)	Registers a text area
void	showRxBuffer(int offset, byte[] buf)	Displays data from the RX buffer
void	showText(String txt)	Displays text in the registered text area

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

prefs

Preferences prefs

io

RegisterIo io

textArea

JTextArea textArea

bytes

byte[] bytes

byteBuffer

ByteBuffer byteBuffer

pageSize

final int pageSize

See Also:

• Constant Field Values

txPages

final int txPages

See Also:

• Constant Field Values

PP

static final byte PP

See Also:

• Constant Field Values

READ

static final byte READ

See Also:

• Constant Field Values

WRDI

static final byte WRDI

See Also:

• Constant Field Values

RDSR

static final byte RDSR

See Also:

• Constant Field Values

WREN

static final byte WREN

See Also:

• Constant Field Values

RDID

static final byte RDID

See Also:

• Constant Field Values

BE

static final byte BE

See Also:

• Constant Field Values

SE

static final byte SE

See Also:

• Constant Field Values

Constructor Details

M25PxxIo

public M25PxxIo(RegisterIo io)

Constructor

Parameters:

io - The IO interface

Method Details

setTextArea

public void setTextArea(JTextArea textArea)

Registers a text area

Parameters:

textArea - The text area

showText

public void showText(String txt)

Displays text in the registered text area

Parameters:

txt - The text to display

clear

public void clear()

Clears the transaction buffer

append

public void append(byte code,
 short opLength)

Appends dataless operation to transaction buffer

Parameters:

code - Opcode

opLength - Length field of the operation in bytes

append

public void append(byte code,
 short opLength,
 byte[] buf)

Appends operation to transaction buffer with data

Parameters:

code - Opcode

opLength - Length field of the operation in bytes

buf - Data to write

op

public void op(int offset,
 boolean waitflag)

Writes instruction to buffer.

End of commands is marked by x"0000" in the next length field.

Parameters:

offset - Offset into buffer where to start writing

waitflag - If true, activate the IO wait feature

bulkErase

void bulkErase(boolean poll,
 JTextField statusTF)

Does bulk erase operation

May take tens of seconds depending on memory type

Parameters:

poll - If true, poll until operation has completed

statusTF - Text field where to write status

sectorErase

void sectorErase(int start)

Does sector erase operation

Parameters:

start - Start address of sector

read

void read(int start)

Does read operation

Parameters:

start - Start address

read

void read(int start,
 int len)

Does read operation

Parameters:

start - Start page

pp

void pp(int start)

Does oage program operation

Currently this is just a test operation that writes a fixed pattern.

Parameters:

start - Start address

program

void program(byte[] buf,
 JTextField statusTF)

Reads the flash data from file and programs flash.

It is most efficient to minimise the number of DEPP transactions therefore buffer several pages into the same DEPP message.

The FPGA buffer is 16Kb so we could do up to 7 pages at a time but we must also take account of the programming time which must not exceed the 10ms DEPP timeout since we are using DEPP wait to synchronise with timeout of 10ms.

Parameters:

buf - Buffer containing data to write

statusTF - Test field where to display status

showRxBuffer

public void showRxBuffer(int offset,
 byte[] buf)

Displays data from the RX buffer

Parameters:

offset - Offset in buffer from where to start reading

buf - Buffer to receive data

getRxBuffer

public void getRxBuffer(int offset,
 byte[] buf)

Reads data from the RX buffer

Parameters:

offset - Offset in buffer from where to start reading

buf - Buffer to receive data

save

public void save(FileOutputStream fo,
 int npages)
          throws IOException

Throws:

IOException