net.sf.jaer.biasgen
Class Pot

java.lang.Object
  java.util.Observable
      net.sf.jaer.biasgen.Pot

All Implemented Interfaces:

java.util.EventListener, java.util.prefs.PreferenceChangeListener

Direct Known Subclasses:

IPot, VPot

public abstract class Pot
extends java.util.Observable
implements java.util.prefs.PreferenceChangeListener

Describes an general bias (pot=potentiometer), This Pot can either be on or off chip. On chip pots are current DACs from Tobi's bias generator design kit, programmed over an SPI interface. Off-chip pots are voltage DACs programmed over SPI.

This class extends Observer so observers can add themselves to be notified when the pot value changes.

Author:

tobi

Nested Class Summary

static class	Pot.Sex the transistor type for bias, N or P or not available (na)
static class	Pot.Type an enum for the type of bias, NORMAL or CASCODE or REFERENCE

Field Summary

protected int	bitValue the current value of the ipot in bits loaded into the shift register
float	CHANGE_FRACTION fraction that pot current changes for increment or decrement
protected Chip	chip The Chip for this Pot
protected int	chipNumber the chip that this ipot sits on in the chain of chips; zero based
protected int	displayPosition the display position within a group
protected java.lang.String	group the 'group' of this IPot, used for grouping related pots
protected static java.util.logging.Logger	log
Masterbias	masterbias the Masterbias supplying reference current to this IPot
protected java.lang.String	name the name of the ipot bias
protected int	numBits the number of bits of resolution for this bias.
protected int	numBytes the number for bytes of 8 bits for this ipot
protected int	pinNumber
protected java.util.prefs.Preferences	prefs Preferences fot this Pot.
protected Pot.Sex	sex n or p type
protected java.lang.String	tooltipString A tooltip to show users
protected Pot.Type	type type of bias, e.g.

Constructor Summary

Pot(Chip chip)
Constructs a new instance of Pot which adds itself as a preference change listener.

Method Summary

void	addObserver(java.util.Observer o)
void	decrementBitValue() decrement pot value by one count
abstract byte[]	getBinaryRepresentation() Computes and returns a new array of bytes representing the bias to be sent over hardware interface to the device.
int	getBitValue() Returns the value of the bias current or voltage in binary form, i.e.
int	getChipNumber()
int	getDisplayPosition()
java.lang.String	getGroup()
int	getMaxBitValue() return the max value representing all stages of current splitter enabled
int	getMinBitValue() no current: zero
java.lang.String	getName()
int	getNumBits() returns the number of shift register/current splitter/DAC bits for the bias value.
int	getNumBytes() bytes for this bias.
abstract float	getPhysicalValue() returns physical value of bias, e.g.
abstract java.lang.String	getPhysicalValueUnits() return units (e.g.
int	getPinNumber()
int	getPreferedBitValue() returns the preference value bit value using prefsKey as the key
Pot.Sex	getSex()
java.lang.String	getTooltipString()
Pot.Type	getType()
void	incrementBitValue() increment pot value by one count
void	loadPreferences() loads and makes active the preference value.
abstract javax.swing.JComponent	makeGUIPotControl() Contructs the UI control for this Pot.
void	preferenceChange(java.util.prefs.PreferenceChangeEvent e) called when there is a preference change for this Preferences node (the Biasgen package node).
protected java.lang.String	prefsKey() Returns the String key by which this pot is known in the Preferences: Pot..
void	resume() restore suspend value (0 if not suspended before
void	setBitValue(int value) set the bit value.
void	setDisplayPosition(int displayPosition)
void	setGroup(java.lang.String group)
void	setName(java.lang.String name) sets the pot name.
void	setNumBits(int n) Sets the number of bits representing this bias.
void	setNumBytes(int numBytes) sets the number of bytes that represent this bias
abstract void	setPhysicalValue(float value) sets physical value of bias
void	setPinNumber(int pinNumber)
void	setSex(Pot.Sex sex)
void	setTooltipString(java.lang.String tooltipString)
void	setType(Pot.Type type)
void	storePreferences() stores as a preference the bit value
void	suspend() set suspend value (zero current), saving old value for resume
java.lang.String	toBitPatternString()
java.lang.String	toString()

Methods inherited from class java.util.Observable

clearChanged, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers, setChanged

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static java.util.logging.Logger log

chip

protected Chip chip

The Chip for this Pot

prefs

protected java.util.prefs.Preferences prefs

Preferences fot this Pot. prefs is assigned in the constructor to the Preferences node for the Chip for this Pot.

type

protected Pot.Type type

type of bias, e.g. normal single FET, or cascode

sex

protected Pot.Sex sex

n or p type

pinNumber

protected int pinNumber

tooltipString

protected java.lang.String tooltipString

A tooltip to show users

name

protected java.lang.String name

the name of the ipot bias

bitValue

protected int bitValue

the current value of the ipot in bits loaded into the shift register

chipNumber

protected int chipNumber

the chip that this ipot sits on in the chain of chips; zero based

group

protected java.lang.String group

the 'group' of this IPot, used for grouping related pots

displayPosition

protected int displayPosition

the display position within a group

masterbias

public transient Masterbias masterbias

the Masterbias supplying reference current to this IPot

numBytes

protected int numBytes

the number for bytes of 8 bits for this ipot

numBits

protected int numBits

the number of bits of resolution for this bias. This number is used to compute the max bit value and also for computing the number of bits or bytes to send to a device

CHANGE_FRACTION

public final float CHANGE_FRACTION

fraction that pot current changes for increment or decrement

See Also:

Constant Field Values

Constructor Detail

Pot

public Pot(Chip chip)

Constructs a new instance of Pot which adds itself as a preference change listener. This Pot adds itself as a PreferenceChangeListener to the Preference object for this preference node (the Biasgen package node), so that preference changes call the method preferenceChange.

Parameters:

chip - the chip for this Pot

Method Detail

preferenceChange

public void preferenceChange(java.util.prefs.PreferenceChangeEvent e)

called when there is a preference change for this Preferences node (the Biasgen package node). If the key of the PreferenceChangeEvent matches our own preference key, then the bit value is set

Specified by:

preferenceChange in interface java.util.prefs.PreferenceChangeListener

Parameters:

e - the PreferenceChangeEvent, issued when new Preferences are loaded

getNumBits

public int getNumBits()

returns the number of shift register/current splitter/DAC bits for the bias value. The total number of bits may be larger if the bias has other configuration bits, e.g. for buffer bias, type of bias, etc.

Returns:

the number of bits

See Also:

ConfigurableIPot

setNumBits

public void setNumBits(int n)

Sets the number of bits representing this bias.

Parameters:

n - the number of bits

getName

public java.lang.String getName()

setName

public void setName(java.lang.String name)

sets the pot name.

Parameters:

name - the string name that is used for the preferences key

getNumBytes

public int getNumBytes()

bytes for this bias. This is numBits/8.

setNumBytes

public void setNumBytes(int numBytes)

sets the number of bytes that represent this bias

Parameters:

numBytes - number of bytes

getBitValue

public int getBitValue()

Returns the value of the bias current or voltage in binary form, i.e. this value will scale the actual value by the reference value. For an on-chip bias current generator the minimum current is about 0, and the maximum is the master current. For an off-chip voltage DAC, the limits are set the by the DAC references.

Returns:

the binary value of the bias

See Also:

getBinaryRepresentation()

setBitValue

public void setBitValue(int value)

set the bit value. Observers are notified if value changes. Value is clipped to hard limits. Every change to bias value must flow through this method.

Parameters:

value - the new bitValue

getChipNumber

public int getChipNumber()

getMaxBitValue

public int getMaxBitValue()

return the max value representing all stages of current splitter enabled

getMinBitValue

public int getMinBitValue()

no current: zero

incrementBitValue

public void incrementBitValue()

increment pot value by one count

decrementBitValue

public void decrementBitValue()

decrement pot value by one count

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

toBitPatternString

public java.lang.String toBitPatternString()

Returns:

string of bits for this ipot shift register

storePreferences

public void storePreferences()

stores as a preference the bit value

loadPreferences

public void loadPreferences()

loads and makes active the preference value. The name should be set before this is called.

getPreferedBitValue

public int getPreferedBitValue()

returns the preference value bit value using prefsKey as the key

prefsKey

protected java.lang.String prefsKey()

Returns the String key by which this pot is known in the Preferences: Pot.. Subclasses, e.g. IPot, sometimes override prefsKey to associate the preferences key with a specific chip.

Returns:

preferences key string

suspend

public void suspend()

set suspend value (zero current), saving old value for resume

See Also:

resume()

resume

public void resume()

restore suspend value (0 if not suspended before

See Also:

suspend()

getGroup

public java.lang.String getGroup()

setGroup

public void setGroup(java.lang.String group)

getPinNumber

public int getPinNumber()

setPinNumber

public void setPinNumber(int pinNumber)

getDisplayPosition

public int getDisplayPosition()

setDisplayPosition

public void setDisplayPosition(int displayPosition)

getTooltipString

public java.lang.String getTooltipString()

setTooltipString

public void setTooltipString(java.lang.String tooltipString)

makeGUIPotControl

public abstract javax.swing.JComponent makeGUIPotControl()

Contructs the UI control for this Pot.

Returns:

the UI component that user uses to control the Pot

getType

public Pot.Type getType()

setType

public void setType(Pot.Type type)

getSex

public Pot.Sex getSex()

setSex

public void setSex(Pot.Sex sex)

getPhysicalValue

public abstract float getPhysicalValue()

returns physical value of bias, e.g. in current amps or voltage volts

Returns:

physical value

setPhysicalValue

public abstract void setPhysicalValue(float value)

sets physical value of bias

Parameters:

value - the physical value, e.g. in amps or volts

getPhysicalValueUnits

public abstract java.lang.String getPhysicalValueUnits()

return units (e.g. A, mV) of physical value of bias

addObserver

public void addObserver(java.util.Observer o)

Overrides:

addObserver in class java.util.Observable

getBinaryRepresentation

public abstract byte[] getBinaryRepresentation()

Computes and returns a new array of bytes representing the bias to be sent over hardware interface to the device.

Returns:

array of bytes to be sent, by convention values are ordered in big endian format so that byte 0 is the most significant byte and is sent first to the hardware