byucc.jhdl.Xilinx.Virtex2
Class buft

java.lang.Object
  byucc.jhdl.base.Nameable
      byucc.jhdl.base.Node
          byucc.jhdl.base.Cell
              byucc.jhdl.base.Structural
                  byucc.jhdl.Logic.LogicGates
                      byucc.jhdl.Logic.LogicStatic
                          byucc.jhdl.Logic.Logic
                              byucc.jhdl.Xilinx.XilinxCL
                                  byucc.jhdl.Xilinx.Virtex2.buft

All Implemented Interfaces:

BooleanFlags, Clockable, PreDefinedSchematic, byucc.jhdl.base.Propagateable, TreeListable, TriStateDriver, UnmappableCell

public final class buft

extends XilinxCL

implements TriStateDriver, UnmappableCell, PreDefinedSchematic

BUFT is a 3-state buffer with input I, output O, and active-Low output enable (T). When T is Low, data on the input of the buffer is transferred to the output. When T is High, the output is high impedance (Z state or off). The outputs of the buffers are connected to horizontal longlines in FPGA architectures. The outputs of separate BUFT symbols can be tied together to form a bus or a multiplexer. Make sure that only one T is Low at one time. If none of the T inputs is active (Low), a 'weak-keeper' circuit (FPGAs) prevents the output bus from floating but does not guarantee that the bus remains at the last value driven onto it. Pull-up resistors can be used to establish a High logic level if all BUFT elements are off XC4000. For Virtex and Spartan2, when all BUFTs on a net are disabled, the net is High.

Field Summary

static CellInterface[]	cell_interface The port interface for: buft i : in (1) t : in (1) o : out (1)
static java.lang.String	cellname The static cellname (netlist reference name) for buft

Fields inherited from class byucc.jhdl.Xilinx.XilinxCL

implicit_interface

Fields inherited from class byucc.jhdl.Logic.Logic

ABOVE, ALIGN_BOTTOM, ALIGN_CENTER, ALIGN_LEFT, ALIGN_LSB, ALIGN_MSB, ALIGN_RIGHT, ALIGN_TOP, BELOW, DOWN, EAST_OF, LEFT_OF, MAX_PACK, NORTH_OF, ON, ONTOP, ONTOP_OF, RIGHT_OF, SOUTH_OF, TOLEFT, TORIGHT, UNCONSTRAINED, UP, WEST_OF

Fields inherited from class byucc.jhdl.Logic.LogicGates

tech_mapper

Fields inherited from class byucc.jhdl.base.Cell

BOOLEAN, CELL_NAME_DECLARATION, CellInterfaceDeterminesUniqueNetlistStructure, DETERMINE_FROM_STRING, GENERICS_DECLARATION, IMPLICIT_INTERFACE_DECLARATION, INTEGER, INTERFACE_DECLARATION, LONG, PORT_IOS_DECLARATION, PORT_NAMES_DECLARATION, PORT_NET_NAMES_DECLARATION, PORT_PROPERTIES, PORT_WIDTHS_DECLARATION, SIGN_EXT, STRING, ZERO_PAD

Fields inherited from interface byucc.jhdl.apps.Viewers.Schematic.PreDefinedSchematic

PreDefinedSchematic_ADD, PreDefinedSchematic_ADDSUB, PreDefinedSchematic_AND, PreDefinedSchematic_BUF, PreDefinedSchematic_CONST, PreDefinedSchematic_GEN, PreDefinedSchematic_GND, PreDefinedSchematic_INC, PreDefinedSchematic_INV, PreDefinedSchematic_MUX, PreDefinedSchematic_NAND, PreDefinedSchematic_NOR, PreDefinedSchematic_OR, PreDefinedSchematic_PULLDOWN, PreDefinedSchematic_PULLUP, PreDefinedSchematic_REG, PreDefinedSchematic_SHL, PreDefinedSchematic_SHR, PreDefinedSchematic_TBUF, PreDefinedSchematic_VCC, PreDefinedSchematic_XNOR, PreDefinedSchematic_XOR

Fields inherited from interface byucc.jhdl.base.BooleanFlags

ANTECEDANT_IS_BEHAVIORALLY_MODELED, ASYNC_PORT, ASYNCHRONOUS_RESOLVED, ATOMICALLY_PLACEABLE, ATOMICALLY_UNMAPPABLE, BEHAVIORALLY_MODELED_BRANCH, CLK_PORT, CLOCK_METHOD_IMPLEMENTED_BY_USER, CLOCK_METHOD_IS_DISABLED, CLOCKABLE_IS_SCHEDULED, DANGLING_IS_OK, DELETE_MARK, FATAL_BUILD_ERROR_OCCURED, HAS_BEEN_TRACED, HAS_USER_SPECIFIED_NAME, HWUPDATE, IMPLICIT_PORT, IN_CLK_PORT, IN_PORT, INOUT_PORT, IO_TYPE_FLAGS, IS_BEHAVIORALLY_MODELED, IS_ON_BUILD_STACK, IS_ON_PROP_LIST, IS_PLACED, METHODS_IMPLEMENTED_BY_USER, NETLISTABLE, ORIG_WIRE_IS_ATOMIC, OUT_PORT, PLACEMENT_IS_LOCKED, PROPAGATE_METHOD_IMPLEMENTED_BY_USER, PROPAGATE_METHOD_IS_DISABLED, RECURSION_FLAG, RESET_METHOD_IMPLEMENTED_BY_USER, SIMULATEABLE, SOURCELESS_IS_OK, SYNC_PORT, VISIBLE

Constructor Summary

protected	buft(Node parent) Used only by child classes to pass up the parent cell.
	buft(Node parent, ArgBlockList abl) Constructs a new buft, connecting its ports as given by the String-Wire pairs in the ArgBlockList.
protected	buft(Node parent, java.lang.String name) Used only by child classes to pass up the parent cell and instance name.
	buft(Node parent, java.lang.String instanceName, ArgBlockList abl) Constructs a new buft, connecting its ports as given by the String-Wire pairs in the ArgBlockList.
	buft(Node parent, java.lang.String instanceName, java.lang.String s0, Wire w0, java.lang.String s1, Wire w1, java.lang.String s2, Wire w2) Constructs a new buft, connecting each Wire to the port whose name is given by the accompanying String parameter The initial String parameter specifies the instance name.
	buft(Node parent, java.lang.String s0, Wire w0, java.lang.String s1, Wire w1, java.lang.String s2, Wire w2) Constructs a new buft, connecting each Wire to the port whose name is given by the accompanying String parameter
	buft(Node parent, java.lang.String instanceName, Wire i, Wire t, Wire o) Constructs a new buft.
	buft(Node parent, Wire i, Wire t, Wire o) Constructs a new buft.

Method Summary

boolean	cellInterfaceDeterminesUniqueNetlistStructure() When false, the default behavior of this method, each cell will list itself separately in a netlist, guaranteeing that the netlist will not have invalid data at the expense of a larger file-size.
java.lang.String	getCellName() Access the cell name associated with a derived class.
boolean	isDrivingOutput() Must be implemented to state whether the cell is driving the tri-state output, based on the enable input.
static void	main(java.lang.String[] argv)
void	propagate() Users defined propagatable behavior using standard JHDL constructs.
static void	test()
int	type() This method returns one of the predefined schematic constants to identify the type of this cell.

Methods inherited from class byucc.jhdl.Xilinx.XilinxCL

connectImplicitPorts

Methods inherited from class byucc.jhdl.Logic.Logic

clockDriver, clockDriver, connect_implicit_ports, constructSubCell, constructSubCellNoImplicitPorts, enableNewPlacement, enableNewPlacement, extend, extend, getDefaultClock, getDefaultTechMapper, getGlobalClock, getSinkCell, getSourceCell, getSourceCell, getSourceLeaf, getSourcePlaceable, getSourcePlaceableLeaf, getSubCellClass, getTechMapHint, getTechMapHint, getTechMapper, growAndShiftl, lockChildPlacement, lsb, lsb, map, map, map, map, map, map, map, map, map, map, map, map, map, map, map, map, map, map, map, msb, msb, msbIndx, netlist, netlist, netlist, netlist, netlist, netlist, netlist, netlist, padClock_o, padClock_o, padClock_o, padClock, padClock, padClock, padIn_o, padIn_o, padIn_o, padIn, padIn, padIn, padInout_o, padInout_o, padInout_o, padInout, padInout, padInout, padOut_o, padOut_o, padOut_o, padOut, padOut, padOut, padOutT_o, padOutT_o, padOutT_o, padOutT, padOutT, padOutT, place, place, place, place, place, place, place, place, place, place, place, place, place, place, place, place, place, printTechMapHints, range, rotate, rotate, scale, scale, setBBox, setDefaultTechMapper, setFloorPlannerIsMaster, setTechMappingEnabled, setWandH, signExtend_o, signExtend, signExtend, sink, source, takeBot_o, takeBot, takeBot, takeBotSigned_o, takeBotSigned, takeTop_o, takeTop, takeTop, techmap, techMappingEnabled, translate, translate, zeroExtend_o, zeroExtend, zeroExtend, zeroExtendRight_o, zeroExtendRight

Methods inherited from class byucc.jhdl.Logic.LogicStatic

add_o, add_o, and_o, and_o, and, and, buf_o, buf_o, buf, buf, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, constant_o, constant_o, constant_o, constant_o, constant_o, constant_o, constant_o, constant_o, constant, constant, constant, constant, constant, constant, constant, constant, constant, constant, gnd_o, gnd_o, gnd, gnd, gnd, gnd, mux_o, mux, nc, nc, nc, nc, nc, nc, not_o, not_o, not, not, or_o, or_o, or, or, reg_o, reg, vcc_o, vcc_o, vcc, vcc, vcc, vcc, wire, wire, wire, wire, xnor_o, xnor_o, xnor, xor_o, xor

Methods inherited from class byucc.jhdl.Logic.LogicGates

add_o, add_o, add_o, add_o, add_o, add_o, add, add, add, add, addsub_o, addsub_o, addsub_o, addsub_o, addsub_o, addsub_o, addsub, addsub, addsub, addsub, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and_o, and, and, and, and, and, and, and, and, and, and, and, and, and, and, and, and, and, and, ashiftr_o, ashiftr, ashiftr, buf_o, buf_o, buf, buf, checkValueRepresentableInWidth, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat_o, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, concat, constant_o, constant_o, constant_o, constant_o, constant_o, constant_o, constant_o, constant_o, constant, constant, constant, constant, constant, constant, constant, constant, constant, constant, gnd_o, gnd_o, gnd, gnd, gnd, gnd, mux_o, mux_o, mux_o, mux_o, mux_o, mux_o, mux, mux, mux, mux, mux, mux, name, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand_o, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nand, nc, nc, nc, nc, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor_o, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, nor, not_o, not_o, not, not, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or_o, or, or, or, or, or, or, or, or, or, or, or, or, or, or, or, or, or, or, pulldown, pulldown, pullup, pullup, reg_o, reg_o, reg_o, reg_o, reg, reg, reg, reg, regc_o, regc_o, regc_o, regc_o, regc, regc, regc, regc, regce_o, regce_o, regce_o, regce_o, regce, regce, regce, regce, regp_o, regp_o, regp_o, regp_o, regp, regp, regp, regp, regpe_o, regpe_o, regpe_o, regpe_o, regpe, regpe, regpe, regpe, regr_o, regr_o, regr_o, regr_o, regr, regr, regr, regr, regre_o, regre_o, regre_o, regre_o, regre, regre, regre, regre, regs_o, regs_o, regs_o, regs_o, regs, regs, regs, regs, regse_o, regse_o, regse_o, regse_o, regse, regse, regse, regse, shiftl_o, shiftl, shiftl, shiftr_o, shiftr, shiftr, sub_o, sub_o, sub_o, sub_o, sub_o, sub_o, sub, sub, sub, sub, tbuf_o, tbuf_o, tbuf, tbuf, vcc_o, vcc_o, vcc, vcc, vcc, vcc, wire, wire, wire, wire, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor_o, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xnor, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor_o, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor, xor

Methods inherited from class byucc.jhdl.base.Structural

behavioralModelIsAvailable, clock, clockMethodIsDisabled, clockMethodIsDisabled, clockMethodIsEnabled, clockMethodIsEnabled, defaultSimulationModelIsBehavioral, hasBeenTraced, hasBeenTraced, hasBehaviorInClockMethod, hasBehaviorInPropagateMethod, isAsynchronouslyScheduled, isAsynchronouslyScheduled, isFallingEdgeTriggered, isReadyToBeAsynchronouslyScheduled, isRisingEdgeTriggered, needsToBeAsynchronouslyScheduled, needsToBeClocked, propagateMethodIsDisabled, propagateMethodIsDisabled, propagateMethodIsEnabled, propagateMethodIsEnabled, reset, willUseHWUpdate, willUseHWUpdate

Methods inherited from class byucc.jhdl.base.Cell

addPort, addPorts, addProperties, addProperties, addProperty, addProperty, addProperty, addProperty, antecedantIsBehaviorallyModeled, antecedantIsBehaviorallyModeled, bind, bind, bind, bind, clk, connect, connectAllWires, connectOptional, disableAllBehavioralModels, disableBehavioralModel, enableBehavioralModel, getArgument, getAttachedPort, getAttachedWire, getAttachedWireNoException, getCellNetlist, getCellNetList, getCellNetlist, getCellNetlist, getDescendents, getFlatNetlist, getFlatNetlistableChildren, getGeneric, getHeight, getNetlistableChildren, getPlacementInfo, getPortProperties, getPortRecord, getPortRecords, getProperties, getProperty, getPropertyValue, getSinkWires, getSourceWires, getUniqueCellName, getWidth, getX, getY, hasPort, hasPorts, in, in, inout, inout, isAsynchronousSourceSinkResolved, isBehaviorallyModeled, isBehaviorallyModeledBranch, isInput, isLeafCell, isNetlistable, isNetlistable, isNetlistablePort, isNetlistLeaf, isNotNetlistable, isNotNetlistablePort, isNotVisible, isOutput, isPlaceable, isPlaceable, isPlaced, isPlaced, isPlacementLocked, isRoot, isSimulateable, isSimulateable, isSink, isSource, isVisible, isVisible, join, lockPlacement, nc, out, out, param, popHierarchy, port, port, port, postorderCheck, preorderCheck, pushHierarchy, pushHierarchy, pushHierarchy, pushHierarchy, pushHierarchyNoImplicitPorts, pushHierarchyNoImplicitPorts, removeAllUnconnectedPorts, removePort, removeProperty, replaceProperty, replaceProperty, resetBehavioralModelsToDefaults, setAsynchronousSourceSinkResolved, setGeneric, setHeight, setNotNetlistable, setNotNetlistable, setNotVisible, setNotVisible, setPlacementInfo, setPortNotNetlistable, setPortNotNetlistable, setProperty, setWidth, subClassDelete, toString, uniquifyCell, userDefinedClockCount, verifyAndCleanup

Methods inherited from class byucc.jhdl.base.Node

addObservable, addSimulatorCallback, checkAll, delete, getBuildingFlag, getChildren, getChildrenEnumeration, getInstanceName, getParent, getParentCell, getRelatives, getSystem, getWires, optimize, orphanAllowed, printAllChildren, printTree, removeSimulatorCallback, setDefaultClock

Methods inherited from class byucc.jhdl.base.Nameable

caseSensitivity, caseSensitivity, disableNameClashChecking, getFullName, getFullNameNoTestBench, getHierNameNoTestBench, getInstanceNo, getInstanceNumber, getLeafName, getLeafName, getRelativeName, getUserName, getUserName, hasUserSpecifiedName, isDescendantOf, setInstanceNumber

Methods inherited from class java.lang.Object

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

Field Detail

cellname

public static final java.lang.String cellname

The static cellname (netlist reference name) for buft

See Also:

Constant Field Values

cell_interface

public static CellInterface[] cell_interface

The port interface for: buft i : in (1) t : in (1) o : out (1)

Constructor Detail

buft

protected buft(Node parent)

Used only by child classes to pass up the parent cell.

Parameters:

parent - Parent cell

buft

protected buft(Node parent,
               java.lang.String name)

Used only by child classes to pass up the parent cell and instance name.

Parameters:

parent - Parent cell

name - Instance name of the cell

buft

public buft(Node parent,
            Wire i,
            Wire t,
            Wire o)

Constructs a new buft.

Parameters:

parent - The parent Cell to the buft

i - The Wire to be connected to input port i

t - The Wire to be connected to input port t

o - The Wire to be connected to output port o

buft

public buft(Node parent,
            java.lang.String instanceName,
            Wire i,
            Wire t,
            Wire o)

Constructs a new buft. The initial String parameter specifies the instance name.

Parameters:

parent - The parent Cell to the buft

instanceName - The instance name of the buft

i - The Wire to be connected to input port i

t - The Wire to be connected to input port t

o - The Wire to be connected to output port o

buft

public buft(Node parent,
            java.lang.String s0,
            Wire w0,
            java.lang.String s1,
            Wire w1,
            java.lang.String s2,
            Wire w2)

Constructs a new buft, connecting each Wire to the port whose name is given by the accompanying String parameter

Parameters:

parent - The parent Cell to the buft

s0 - The name of the port to which w0 will be connected

w0 - The Wire to be connected to the port specified by s0

s1 - The name of the port to which w1 will be connected

w1 - The Wire to be connected to the port specified by s1

s2 - The name of the port to which w2 will be connected

w2 - The Wire to be connected to the port specified by s2

buft

public buft(Node parent,
            java.lang.String instanceName,
            java.lang.String s0,
            Wire w0,
            java.lang.String s1,
            Wire w1,
            java.lang.String s2,
            Wire w2)

Constructs a new buft, connecting each Wire to the port whose name is given by the accompanying String parameter The initial String parameter specifies the instance name.

Parameters:

parent - The parent Cell to the buft

instanceName - The instance name of the buft

s0 - The name of the port to which w0 will be connected

w0 - The Wire to be connected to the port specified by s0

s1 - The name of the port to which w1 will be connected

w1 - The Wire to be connected to the port specified by s1

s2 - The name of the port to which w2 will be connected

w2 - The Wire to be connected to the port specified by s2

buft

public buft(Node parent,
            ArgBlockList abl)

Constructs a new buft, connecting its ports as given by the String-Wire pairs in the ArgBlockList. Any generic assignments are made through String-String pairs in the ArgBlockList.

Parameters:

parent - The parent Cell to the buft

abl - The list of String-Wire pairs for port assignments, and String-String pairs for generic assignments.

buft

public buft(Node parent,
            java.lang.String instanceName,
            ArgBlockList abl)

Constructs a new buft, connecting its ports as given by the String-Wire pairs in the ArgBlockList. Any generic assignments are made through String-String pairs in the ArgBlockList. The initial String parameter is the instance name.

Parameters:

parent - The parent Cell to the buft

instanceName - The instance name of the buft

abl - The list of String-Wire pairs for port assignments, and String-String pairs for generic assignments.

Method Detail

getCellName

public java.lang.String getCellName()

Description copied from class: Cell

Access the cell name associated with a derived class. The cellname field is lazily evaluated on the first call of this method. Can be overriden to make cellname different by instance. If the field does not exist, this defaults to the classname.

Overrides:

getCellName in class Cell

Returns:

the cell name associated with a derived class, null if not declared.

cellInterfaceDeterminesUniqueNetlistStructure

public final boolean cellInterfaceDeterminesUniqueNetlistStructure()

Description copied from class: Cell

When false, the default behavior of this method, each cell will list itself separately in a netlist, guaranteeing that the netlist will not have invalid data at the expense of a larger file-size. Overriding this method to return true allows JHDL to save memory and netlists to be smaller by sharing the netlist structures that are guaranteed to be identical. NOTE: Do not override this unless every possible condition responsible for structural differences in a class (types and amount of children cells created, and arrangements of wires connected to ports) is included in the cellInterface[] of that class.

Overrides:

cellInterfaceDeterminesUniqueNetlistStructure in class Cell

Returns:

false if not overridden, preventing all memory sharing

propagate

public final void propagate()

Description copied from class: Structural

Users defined propagatable behavior using standard JHDL constructs. The simulator detects whether propagate() has been implemented by calling function directly and checking for an exception.

Specified by:

propagate in interface byucc.jhdl.base.Propagateable

Overrides:

propagate in class Structural

type

public int type()

Description copied from interface: PreDefinedSchematic

This method returns one of the predefined schematic constants to identify the type of this cell.

Specified by:

type in interface PreDefinedSchematic

Returns:

A predefined schematic constant

isDrivingOutput

public boolean isDrivingOutput()

Description copied from interface: TriStateDriver

Must be implemented to state whether the cell is driving the tri-state output, based on the enable input.

Specified by:

isDrivingOutput in interface TriStateDriver

Returns:

true if the driver is presently driving the output.

main

public static void main(java.lang.String[] argv)

test

public static void test()