byucc.jhdl.Xilinx.Virtex.Modules
Class delay

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.Virtex.Modules.delay

All Implemented Interfaces:

BooleanFlags, Clockable, byucc.jhdl.base.Propagateable, TreeListable

public class delay

extends Logic

Generic Delay Line

This delays a data word for a given number of cycles. The delay line can be stalled by setting clk_en=0. The delay can be for any number of cycles, and is specified at construction time. The input and output can each be up to 64 bits wide and must be the same width.

Virtex

If the delay line is directly driven by a ConstantSource, the delay line is internally optimized away.

Xilinx Virtex

Implementation

For Virtex, the SRL16E shift registers are used. Each register can delay the signal for 1-16 cycles. The four-bit address determines the delay: delay = addr+1. For instance, an address of 5 delays the signal for 6 cycles. For delays greater than 16, the registers are simply cascaded. All of them have an address of 15 except for the last one, which has an address corresponding to the remaining delay. As an example, a delay of 35 would have three registers, of addresses 15, 15, and 2.
Note: If you need to clear your delay, the SRL's will not clear their data! Take that into account in your design.

Slice count: The above CLB count generator for XC4000 is still pretty accurate for counting slices in Virtex. If the delay is for less than 64 cycles, then there will be either 2 or 4 more slices than the above counter generates. If the delay is for more than 64 cycles, then divide the number of delay cycles by 64, round up to the nearest integer, multiply this number by 2, and that is the number of slices to add to what the CLB count generator above gives you.

Slice placement:

The orientation of the Slices is as follows: The downcounter(s) are placed in two columns on the left hand side, either two Slices high or four Slices high, depending on whether only one downcounter was used or two. To the right of the downcounters are the rams holding the data. Here is the height of the Slice stack according to the number of delay cycles:

1-16 cycles: 2 Slices high

17-32 cycles: 4 Slices high

33-48 cycles: 6 Slices high

48-64 cycles: 8 Slices high

Version:

$Revision: 1.6 $

Author:

Dan Baker

Field Summary

static CellInterface[]	cell_interface
static java.lang.String	cellname The input is a generic width

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, 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.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

delay(Node parent, int num_of_cyc, Wire in, Wire clk_en, Wire out)

delay(Node parent, int num_of_cyc, Wire in, Wire clk_en, Wire out, java.lang.String name)

delay(Node parent, int num_of_cyc, Wire clk, Wire in, Wire clk_en, Wire out)

delay(Node parent, int num_of_cyc, Wire clk, Wire in, Wire clk_en, Wire out, java.lang.String name)

Method Summary

void	clock() Clock is used in the behavioral model and is called once per clock cycle
static int	compute() No computation necessary in this class, so compute always returns a zero
void	connectImplicitPort()
protected boolean	defaultSimulationModelIsBehavioral() Default simulation model is behavioral
java.lang.String	getCellName() Access the cell name associated with a derived class.
long	getSize()
void	propagate() Propagate is used only if the number of delay cycles = 0
void	reset() Resets the output to zero

Methods inherited from class byucc.jhdl.Logic.Logic

clockDriver, clockDriver, connect_implicit_ports, connectImplicitPorts, 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, clockMethodIsDisabled, clockMethodIsDisabled, clockMethodIsEnabled, clockMethodIsEnabled, hasBeenTraced, hasBeenTraced, hasBehaviorInClockMethod, hasBehaviorInPropagateMethod, isAsynchronouslyScheduled, isAsynchronouslyScheduled, isFallingEdgeTriggered, isReadyToBeAsynchronouslyScheduled, isRisingEdgeTriggered, needsToBeAsynchronouslyScheduled, needsToBeClocked, propagateMethodIsDisabled, propagateMethodIsDisabled, propagateMethodIsEnabled, propagateMethodIsEnabled, willUseHWUpdate, willUseHWUpdate

Methods inherited from class byucc.jhdl.base.Cell

addPort, addPorts, addProperties, addProperties, addProperty, addProperty, addProperty, addProperty, antecedantIsBehaviorallyModeled, antecedantIsBehaviorallyModeled, bind, bind, bind, bind, cellInterfaceDeterminesUniqueNetlistStructure, 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

cell_interface

public static CellInterface[] cell_interface

cellname

public static final java.lang.String cellname

The input is a generic width

See Also:

Constant Field Values

Constructor Detail

delay

public delay(Node parent,
             int num_of_cyc,
             Wire in,
             Wire clk_en,
             Wire out)

delay

public delay(Node parent,
             int num_of_cyc,
             Wire clk,
             Wire in,
             Wire clk_en,
             Wire out)

delay

public delay(Node parent,
             int num_of_cyc,
             Wire in,
             Wire clk_en,
             Wire out,
             java.lang.String name)

delay

public delay(Node parent,
             int num_of_cyc,
             Wire clk,
             Wire in,
             Wire clk_en,
             Wire out,
             java.lang.String name)

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.

getSize

public long getSize()

reset

public void reset()

Resets the output to zero

Specified by:

reset in interface Clockable

Overrides:

reset in class Structural

clock

public void clock()

Clock is used in the behavioral model and is called once per clock cycle

Specified by:

clock in interface Clockable

Overrides:

clock in class Structural

propagate

public void propagate()

Propagate is used only if the number of delay cycles = 0

Specified by:

propagate in interface byucc.jhdl.base.Propagateable

Overrides:

propagate in class Structural

defaultSimulationModelIsBehavioral

protected boolean defaultSimulationModelIsBehavioral()

Default simulation model is behavioral

Overrides:

defaultSimulationModelIsBehavioral in class Structural

Returns:

true if TestBench or leafCell, false otherwise.

connectImplicitPort

public void connectImplicitPort()

compute

public static int compute()

No computation necessary in this class, so compute always returns a zero