byucc.jhdl.Logic.Modules.FloatingPoint
Class FPAddSub

java.lang.Object
  extended bybyucc.jhdl.base.Nameable
      extended bybyucc.jhdl.base.Node
          extended bybyucc.jhdl.base.Cell
              extended bybyucc.jhdl.base.Structural
                  extended bybyucc.jhdl.Logic.LogicGates
                      extended bybyucc.jhdl.Logic.LogicStatic
                          extended bybyucc.jhdl.Logic.Logic
                              extended bybyucc.jhdl.Logic.Modules.FloatingPoint.FPAddSub
All Implemented Interfaces:
BooleanFlags, Clockable, byucc.jhdl.base.Propagateable, TreeListable

public class FPAddSub
extends Logic

General Description


FPAddSub Block Diagram


Floating Point Adder with parameterizeable exponent and mantissa

FPAddSub takes two inputs formatted according to the IEEE floating point standard, and adds them together using floating point arithmetic. The inputs and output must all be the same size (width).

Usage Examples

Required import:
     import byucc.jhdl.Logic.Modules.FloatingPoint.*;

Constructor Syntax:

The constructor takes input wires, subtract flag, output wire, error flags, and two parameters describing the form of the adder.

FPAddSub(parent,?a, b, addsub, output, underflow, overflow, pipe_level, exponent_width )

The parameters are described here:

parentParent of this cell, this is standard for all JHDL cells
a, bInputs, formatted according to IEEE floating point format
addsubLow-asserted causes the unit to add, high asserted performs a subtract
outputOutput of the operation, also formatted according to IEEE F.P.
underflow, overflowThese outputs are asserted on an error
pipe_level0 - fully combinational
1 - ??? stages
2 - fully pipelined, ??? stages
exponenent_widthHow many bits of the inputs and output are dedicated to the exponent field

For all available constructors, see Constructor Summary or Constructor Detail.

Implementation

The circuit is designed using components only from the byucc.jhdl.Logic package. The circuit is not placed, since the tools often do a better job anyway.

Version:
1.0
Author:
Eric Roesler

Field Summary
static CellInterface[] cell_interface
           
static java.lang.String CELL_NAME
           
 
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
FPAddSub(Node parent, Wire a, Wire b, Wire addsub, Wire output, Wire underflow, Wire overflow, int exponent_width, int pipe_level)
           
FPAddSub(Node parent, Wire a, Wire b, Wire addsub, Wire output, Wire underflow, Wire overflow, int exponent_width, int pipe_level, java.lang.String instance_name)
           
 
Method Summary
static int calculateLatency(int width, int pipe_level)
           
 void clock()
          Users define synchronous behavior in this method using standard JHDL constructs.
 void compute(BV a, BV b, long addsub, BV output_value, int[] output_flags, int width, int exponent_width)
           
protected  boolean defaultSimulationModelIsBehavioral()
          The default simulation model is structural for Structural cells.
 int getLatency()
           
 void propagate()
          Users defined propagatable behavior using standard JHDL constructs.
 void reset()
          If you define a behavior, you must also define a reset method for resetting the synchonous part of your model.
protected  void setLatency()
           
 
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,