com.dalsemi.onewire.container
Class MemoryBankScratchCRCPW

java.lang.Object
  |
  +--com.dalsemi.onewire.container.MemoryBankScratch
        |
        +--com.dalsemi.onewire.container.MemoryBankScratchEx
              |
              +--com.dalsemi.onewire.container.MemoryBankScratchCRCPW

All Implemented Interfaces:

MemoryBank, PagedMemoryBank, com.dalsemi.onewire.container.ScratchPad

public class MemoryBankScratchCRCPW

extends com.dalsemi.onewire.container.MemoryBankScratchEx

Memory bank class for the Scratchpad section of NVRAM iButtons and 1-Wire devices with password protected memory pages.

Version:

1.00, 11 Aug 2002

Author:

SH

Field Summary

boolean	enablePower Enable Provided Power for some Password checking.
static byte	READ_SCRATCHPAD_COMMAND Read Scratchpad Command
static byte	WRITE_SCRATCHPAD_COMMAND Write Scratchpad Command

Constructor Summary

MemoryBankScratchCRCPW(PasswordContainer ibutton)
Memory bank contstuctor.

Method Summary

void	checkSpeed() Check the device speed if has not been done before or if an error was detected.
void	copyScratchpad(int startAddr, int len) Copy the scratchpad page to memory.
void	forceVerify() Set the flag to indicate the next 'checkSpeed()' will force a speed set and verify 'doSpeed()'.
String	getBankDescription() Query to see get a string description of the current memory bank.
String	getExtraInfoDescription() Query to get a string description of what is contained in the Extra Informationed return when reading pages in the current memory bank.
int	getExtraInfoLength() Query to get the length in bytes of extra information that is read when read a page in the current memory bank.
int	getMaxPacketDataLength() Query to get Maximum data page length in bytes for a packet read or written in the current memory bank.
int	getNumberPages() Query to get the number of pages in current memory bank.
int	getPageLength() Query to get page length in bytes in current memory bank.
int	getSize() Query to get the memory bank size in bytes.
int	getStartPhysicalAddress() Query to get the starting physical address of this bank.
boolean	hasExtraInfo() Checks to see if this memory bank's pages deliver extra information outside of the normal data space, when read.
boolean	hasPageAutoCRC() Query to see if current memory bank pages can be read with the contents being verified by a device generated CRC.
boolean	haveExtraInfo() Deprecated. As of 1-Wire API 0.01, replaced by MemoryBankScratch.hasExtraInfo()
boolean	isGeneralPurposeMemory() Query to see if the current memory bank is general purpose user memory.
boolean	isNonVolatile() Query to see if current memory bank non-volatile.
boolean	isReadOnly() Query to see if current memory bank is read only.
boolean	isReadWrite() Query to see if current memory bank is read/write.
boolean	isWriteOnce() Query to see if current memory bank is write write once such as with EPROM technology.
boolean	needsPowerDelivery() Query to see if current memory bank pages need the adapter to have a 'PowerDelivery' feature in order to write to the memory.
boolean	needsProgramPulse() Query to see if current memory bank pages need the adapter to have a 'ProgramPulse' in order to write to the memory.
void	read(int startAddr, boolean readContinue, byte[] readBuf, int offset, int len) Read memory in the current bank with no CRC checking (device or data).
void	readPage(int page, boolean readContinue, byte[] readBuf, int offset) Read page in the current bank with no CRC checking (device or data).
void	readPage(int page, boolean readContinue, byte[] readBuf, int offset, byte[] extraInfo) Read page with extra information in the current bank with no CRC checking (device or data).
void	readPageCRC(int page, boolean readContinue, byte[] readBuf, int offset) Read a complete memory page with CRC verification provided by the device.
void	readPageCRC(int page, boolean readContinue, byte[] readBuf, int offset, byte[] extraInfo) Read a complete memory page with CRC verification provided by the device with extra information.
int	readPagePacket(int page, boolean readContinue, byte[] readBuf, int offset) Read a Universal Data Packet.
int	readPagePacket(int page, boolean readContinue, byte[] readBuf, int offset, byte[] extraInfo) Read a Universal Data Packet and extra information.
void	readScratchpad(byte[] readBuf, int offset, int len, byte[] extraInfo) Read the scratchpad page of memory from a NVRAM device This method reads and returns the entire scratchpad after the byte offset regardless of the actual ending offset
void	setWriteVerification(boolean doReadVerf) Set the write verification for the 'write()' method.
void	write(int startAddr, byte[] writeBuf, int offset, int len) Write memory in the current bank.
void	writePagePacket(int page, byte[] writeBuf, int offset, int len) Write a Universal Data Packet.
void	writeScratchpad(int startAddr, byte[] writeBuf, int offset, int len) Write to the scratchpad page of memory a NVRAM device.

Methods inherited from class java.lang.Object

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

Field Detail

enablePower

public boolean enablePower

Enable Provided Power for some Password checking.

WRITE_SCRATCHPAD_COMMAND

public static final byte WRITE_SCRATCHPAD_COMMAND

Write Scratchpad Command

READ_SCRATCHPAD_COMMAND

public static final byte READ_SCRATCHPAD_COMMAND

Read Scratchpad Command

Constructor Detail

MemoryBankScratchCRCPW

public MemoryBankScratchCRCPW(PasswordContainer ibutton)

Memory bank contstuctor. Requires reference to the OneWireContainer this memory bank resides on.

Method Detail

readPageCRC

public void readPageCRC(int page,
                        boolean readContinue,
                        byte[] readBuf,
                        int offset)
                 throws OneWireIOException,
                        OneWireException

Read a complete memory page with CRC verification provided by the device. Not supported by all devices. See the method 'hasPageAutoCRC()'.

Overrides:

readPageCRC in class com.dalsemi.onewire.container.MemoryBankScratch

Parameters:

page - page number to read

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new readPagePacket() continious where the last one stopped and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to put data read. Must have at least 'getMaxPacketDataLength()' elements.

offset - offset into readBuf to place data

Throws:

OneWireIOException -

OneWireException -

readPageCRC

public void readPageCRC(int page,
                        boolean readContinue,
                        byte[] readBuf,
                        int offset,
                        byte[] extraInfo)
                 throws OneWireIOException,
                        OneWireException

Read a complete memory page with CRC verification provided by the device with extra information. Not supported by all devices. See the method 'hasPageAutoCRC()'. See the method 'hasExtraInfo()' for a description of the optional extra information.

Overrides:

readPageCRC in class com.dalsemi.onewire.container.MemoryBankScratch

Parameters:

page - page number to read

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new readPagePacket() continious where the last one stopped and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to put data read. Must have at least 'getMaxPacketDataLength()' elements.

offset - offset into readBuf to place data

extraInfo - byte array to put extra info read into

Throws:

OneWireIOException -

OneWireException -

readScratchpad

public void readScratchpad(byte[] readBuf,
                           int offset,
                           int len,
                           byte[] extraInfo)
                    throws OneWireIOException,
                           OneWireException

Read the scratchpad page of memory from a NVRAM device This method reads and returns the entire scratchpad after the byte offset regardless of the actual ending offset

Overrides:

readScratchpad in class com.dalsemi.onewire.container.MemoryBankScratch

Parameters:

readBuf - byte array to place read data into length of array is always pageLength.

offset - offset into readBuf to pug data

len - length in bytes to read

extraInfo - byte array to put extra info read into (TA1, TA2, e/s byte) length of array is always extraInfoLength. Can be 'null' if extra info is not needed.

Throws:

OneWireIOException -

OneWireException -

copyScratchpad

public void copyScratchpad(int startAddr,
                           int len)
                    throws OneWireIOException,
                           OneWireException

Copy the scratchpad page to memory.

Overrides:

copyScratchpad in class com.dalsemi.onewire.container.MemoryBankScratchEx

Parameters:

startAddr - starting address

len - length in bytes that was written already

Throws:

OneWireIOException -

OneWireException -

writeScratchpad

public void writeScratchpad(int startAddr,
                            byte[] writeBuf,
                            int offset,
                            int len)
                     throws OneWireIOException,
                            OneWireException

Write to the scratchpad page of memory a NVRAM device.

Overrides:

writeScratchpad in class com.dalsemi.onewire.container.MemoryBankScratchEx

Parameters:

startAddr - starting address

writeBuf - byte array containing data to write

offset - offset into readBuf to place data

len - length in bytes to write

Throws:

OneWireIOException -

OneWireException -

getBankDescription

public String getBankDescription()

Query to see get a string description of the current memory bank.

Specified by:

getBankDescription in interface MemoryBank

Returns:

String containing the memory bank description

isGeneralPurposeMemory

public boolean isGeneralPurposeMemory()

Query to see if the current memory bank is general purpose user memory. If it is NOT then it is Memory-Mapped and writing values to this memory will affect the behavior of the 1-Wire device.

Specified by:

isGeneralPurposeMemory in interface MemoryBank

Returns:

'true' if current memory bank is general purpose

isReadWrite

public boolean isReadWrite()

Query to see if current memory bank is read/write.

Specified by:

isReadWrite in interface MemoryBank

Returns:

'true' if current memory bank is read/write

isWriteOnce

public boolean isWriteOnce()

Query to see if current memory bank is write write once such as with EPROM technology.

Specified by:

isWriteOnce in interface MemoryBank

Returns:

'true' if current memory bank can only be written once

isReadOnly

public boolean isReadOnly()

Query to see if current memory bank is read only.

Specified by:

isReadOnly in interface MemoryBank

Returns:

'true' if current memory bank can only be read

isNonVolatile

public boolean isNonVolatile()

Query to see if current memory bank non-volatile. Memory is non-volatile if it retains its contents even when removed from the 1-Wire network.

Specified by:

isNonVolatile in interface MemoryBank

Returns:

'true' if current memory bank non volatile.

needsProgramPulse

public boolean needsProgramPulse()

Query to see if current memory bank pages need the adapter to have a 'ProgramPulse' in order to write to the memory.

Specified by:

needsProgramPulse in interface MemoryBank

Returns:

'true' if writing to the current memory bank pages requires a 'ProgramPulse'.

needsPowerDelivery

public boolean needsPowerDelivery()

Query to see if current memory bank pages need the adapter to have a 'PowerDelivery' feature in order to write to the memory.

Specified by:

needsPowerDelivery in interface MemoryBank

Returns:

'true' if writing to the current memory bank pages requires 'PowerDelivery'.

getStartPhysicalAddress

public int getStartPhysicalAddress()

Query to get the starting physical address of this bank. Physical banks are sometimes sub-divided into logical banks due to changes in attributes.

Specified by:

getStartPhysicalAddress in interface MemoryBank

Returns:

physical starting address of this logical bank.

getSize

public int getSize()

Query to get the memory bank size in bytes.

Specified by:

getSize in interface MemoryBank

Returns:

memory bank size in bytes.

getNumberPages

public int getNumberPages()

Query to get the number of pages in current memory bank.

Specified by:

getNumberPages in interface PagedMemoryBank

Returns:

number of pages in current memory bank

getPageLength

public int getPageLength()

Query to get page length in bytes in current memory bank.

Specified by:

getPageLength in interface PagedMemoryBank

Returns:

page length in bytes in current memory bank

getMaxPacketDataLength

public int getMaxPacketDataLength()

Query to get Maximum data page length in bytes for a packet read or written in the current memory bank. See the 'ReadPagePacket()' and 'WritePagePacket()' methods. This method is only usefull if the current memory bank is general purpose memory.

Specified by:

getMaxPacketDataLength in interface PagedMemoryBank

Returns:

max packet page length in bytes in current memory bank

hasPageAutoCRC

public boolean hasPageAutoCRC()

Query to see if current memory bank pages can be read with the contents being verified by a device generated CRC. This is used to see if the 'ReadPageCRC()' can be used.

Specified by:

hasPageAutoCRC in interface PagedMemoryBank

Returns:

'true' if current memory bank can be read with self generated CRC.

haveExtraInfo

public boolean haveExtraInfo()

Deprecated. As of 1-Wire API 0.01, replaced by MemoryBankScratch.hasExtraInfo()

Query to see if current memory bank pages when read deliver extra information outside of the normal data space. Examples of this may be a redirection byte, counter, tamper protection bytes, or SHA-1 result. If this method returns true then the methods 'ReadPagePacket()' and 'readPageCRC()' with 'extraInfo' parameter can be used.

Specified by:

haveExtraInfo in interface PagedMemoryBank

Returns:

'true' if reading the current memory bank pages provides extra information.

hasExtraInfo

public boolean hasExtraInfo()

Checks to see if this memory bank's pages deliver extra information outside of the normal data space, when read. Examples of this may be a redirection byte, counter, tamper protection bytes, or SHA-1 result. If this method returns true then the methods with an 'extraInfo' parameter can be used: readPage, readPageCRC, and readPagePacket.

Specified by:

hasExtraInfo in interface PagedMemoryBank

Returns:

true if reading the this memory bank's pages provides extra information

Since:

1-Wire API 0.01

See Also:

readPage(extra), readPageCRC(extra), readPagePacket(extra)

getExtraInfoLength

public int getExtraInfoLength()

Query to get the length in bytes of extra information that is read when read a page in the current memory bank. See 'hasExtraInfo()'.

Specified by:

getExtraInfoLength in interface PagedMemoryBank

Returns:

number of bytes in Extra Information read when reading pages in the current memory bank.

getExtraInfoDescription

public String getExtraInfoDescription()

Query to get a string description of what is contained in the Extra Informationed return when reading pages in the current memory bank. See 'hasExtraInfo()'.

Specified by:

getExtraInfoDescription in interface PagedMemoryBank

Returns:

string describing extra information.

setWriteVerification

public void setWriteVerification(boolean doReadVerf)

Set the write verification for the 'write()' method.

Specified by:

setWriteVerification in interface MemoryBank

Parameters:

doReadVerf - true (default) verify write in 'write' false, don't verify write (used on Write-Once bit manipulation)

read

public void read(int startAddr,
                 boolean readContinue,
                 byte[] readBuf,
                 int offset,
                 int len)
          throws OneWireIOException,
                 OneWireException

Read memory in the current bank with no CRC checking (device or data). The resulting data from this API may or may not be what is on the 1-Wire device. It is recommends that the data contain some kind of checking (CRC) like in the readPagePacket() method or have the 1-Wire device provide the CRC as in readPageCRC(). readPageCRC() however is not supported on all memory types, see 'hasPageAutoCRC()'. If neither is an option then this method could be called more then once to at least verify that the same thing is read consistantly.

Specified by:

read in interface MemoryBank

Parameters:

startAddr - starting address

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new read() continious where the last one led off and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to place read data into

offset - offset into readBuf to place data

len - length in bytes to read

Throws:

OneWireIOException -

OneWireException -

write

public void write(int startAddr,
                  byte[] writeBuf,
                  int offset,
                  int len)
           throws OneWireIOException,
                  OneWireException

Write memory in the current bank. It is recommended that when writing data that some structure in the data is created to provide error free reading back with read(). Or the method 'writePagePacket()' could be used which automatically wraps the data in a length and CRC. When using on Write-Once devices care must be taken to write into into empty space. If write() is used to write over an unlocked page on a Write-Once device it will fail. If write verification is turned off with the method 'setWriteVerification(false)' then the result will be an 'AND' of the existing data and the new data.

Specified by:

write in interface MemoryBank

Parameters:

startAddr - starting address

writeBuf - byte array containing data to write

offset - offset into writeBuf to get data

len - length in bytes to write

Throws:

OneWireIOException -

OneWireException -

readPage

public void readPage(int page,
                     boolean readContinue,
                     byte[] readBuf,
                     int offset)
              throws OneWireIOException,
                     OneWireException

Read page in the current bank with no CRC checking (device or data). The resulting data from this API may or may not be what is on the 1-Wire device. It is recommends that the data contain some kind of checking (CRC) like in the readPagePacket() method or have the 1-Wire device provide the CRC as in readPageCRC(). readPageCRC() however is not supported on all memory types, see 'hasPageAutoCRC()'. If neither is an option then this method could be called more then once to at least verify that the same thing is read consistantly.

Specified by:

readPage in interface PagedMemoryBank

Parameters:

page - page number to read packet from

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new readPage() continious where the last one led off and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to place read data into

offset - offset into readBuf to place data

Throws:

OneWireIOException -

OneWireException -

readPage

public void readPage(int page,
                     boolean readContinue,
                     byte[] readBuf,
                     int offset,
                     byte[] extraInfo)
              throws OneWireIOException,
                     OneWireException

Read page with extra information in the current bank with no CRC checking (device or data). The resulting data from this API may or may not be what is on the 1-Wire device. It is recommends that the data contain some kind of checking (CRC) like in the readPagePacket() method or have the 1-Wire device provide the CRC as in readPageCRC(). readPageCRC() however is not supported on all memory types, see 'hasPageAutoCRC()'. If neither is an option then this method could be called more then once to at least verify that the same thing is read consistantly. See the method 'hasExtraInfo()' for a description of the optional extra information some devices have.

Specified by:

readPage in interface PagedMemoryBank

Parameters:

page - page number to read packet from

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new readPage() continious where the last one led off and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to place read data into

offset - offset into readBuf to place data

extraInfo - byte array to put extra info read into

Throws:

OneWireIOException -

OneWireException -

readPagePacket

public int readPagePacket(int page,
                          boolean readContinue,
                          byte[] readBuf,
                          int offset)
                   throws OneWireIOException,
                          OneWireException

Read a Universal Data Packet. The Universal Data Packet always starts on page boundaries but can end anywhere in the page. The structure specifies the length of data bytes not including the length byte and the CRC16 bytes. There is one length byte. The CRC16 is first initialized to the page number. This provides a check to verify the page that was intended is being read. The CRC16 is then calculated over the length and data bytes. The CRC16 is then inverted and stored low byte first followed by the high byte. This is structure is used by this method to verify the data but is not returned, only the data payload is returned.

Specified by:

readPagePacket in interface PagedMemoryBank

Parameters:

page - page number to read packet from

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new readPagePacket() continious where the last one stopped and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to put data read. Must have at least 'getMaxPacketDataLength()' elements.

offset - offset into readBuf to place data

Returns:

number of data bytes read from the device and written to readBuf at the offset.

Throws:

OneWireIOException -

OneWireException -

readPagePacket

public int readPagePacket(int page,
                          boolean readContinue,
                          byte[] readBuf,
                          int offset,
                          byte[] extraInfo)
                   throws OneWireIOException,
                          OneWireException

Read a Universal Data Packet and extra information. See the method 'readPagePacket()' for a description of the packet structure. See the method 'hasExtraInfo()' for a description of the optional extra information some devices have.

Specified by:

readPagePacket in interface PagedMemoryBank

Parameters:

page - page number to read packet from

readContinue - if 'true' then device read is continued without re-selecting. This can only be used if the new readPagePacket() continious where the last one stopped and it is inside a 'beginExclusive/endExclusive' block.

readBuf - byte array to put data read. Must have at least 'getMaxPacketDataLength()' elements.

offset - offset into readBuf to place data

extraInfo - byte array to put extra info read into

Returns:

number of data bytes read from the device and written to readBuf at the offset.

Throws:

OneWireIOException -

OneWireException -

writePagePacket

public void writePagePacket(int page,
                            byte[] writeBuf,
                            int offset,
                            int len)
                     throws OneWireIOException,
                            OneWireException

Write a Universal Data Packet. See the method 'readPagePacket()' for a description of the packet structure.

Specified by:

writePagePacket in interface PagedMemoryBank

Parameters:

page - page number to write packet to

writeBuf - data byte array to write

offset - offset into writeBuf where data to write is

len - number of bytes to write

Throws:

OneWireIOException -

OneWireException -

checkSpeed

public void checkSpeed()
                throws OneWireIOException,
                       OneWireException

Check the device speed if has not been done before or if an error was detected.

Specified by:

checkSpeed in interface com.dalsemi.onewire.container.ScratchPad

Throws:

OneWireIOException -

OneWireException -

forceVerify

public void forceVerify()

Set the flag to indicate the next 'checkSpeed()' will force a speed set and verify 'doSpeed()'.

Specified by:

forceVerify in interface com.dalsemi.onewire.container.ScratchPad