plugins/net.mograsim.machine/src/net/mograsim/machine/mi/components/CoreMicroInstructionMemory.java

   1 package net.mograsim.machine.mi.components;
   2
   3 import java.util.List;
   4
   5 import net.mograsim.logic.core.components.BasicCoreComponent;
   6 import net.mograsim.logic.core.timeline.Timeline;
   7 import net.mograsim.logic.core.timeline.TimelineEventHandler;
   8 import net.mograsim.logic.core.types.Bit;
   9 import net.mograsim.logic.core.types.BitVector;
  10 import net.mograsim.logic.core.wires.CoreWire.ReadEnd;
  11 import net.mograsim.logic.core.wires.CoreWire.ReadWriteEnd;
  12 import net.mograsim.machine.MemoryObserver;
  13 import net.mograsim.machine.mi.MicroInstructionMemory;
  14 import net.mograsim.machine.mi.MicroInstructionMemoryDefinition;
  15
  16 public class CoreMicroInstructionMemory extends BasicCoreComponent
  17 {
  18         private final ReadWriteEnd data;
  19         private final ReadEnd address;
  20         private final MicroInstructionMemoryDefinition definition;
  21         private final MemoryObserver memObs;
  22         private MicroInstructionMemory memory;
  23
  24         public CoreMicroInstructionMemory(Timeline timeline, int processTime, MicroInstructionMemoryDefinition definition, ReadWriteEnd data,
  25                         ReadEnd address)
  26         {
  27                 super(timeline, processTime);
  28                 if (data.width() != definition.getMicroInstructionDefinition().sizeInBits())
  29                         throw new IllegalArgumentException(
  30                                         String.format("Bit width of data wire does not match microinstruction memory definition. Expected: %d Actual: %d",
  31                                                         definition.getMicroInstructionDefinition().sizeInBits(), data.width()));
  32                 if (address.width() != definition.getMemoryAddressBits())
  33                         throw new IllegalArgumentException(
  34                                         String.format("Bit width of address wire does not match microinstruction memory definition. Expected: %d Actual: %d",
  35                                                         definition.getMemoryAddressBits(), address.width()));
  36
  37                 this.data = data;
  38                 this.address = address;
  39                 this.definition = definition;
  40                 this.memObs = a -> update();
  41                 address.registerObserver(this);
  42         }
  43
  44         public void setMemory(MicroInstructionMemory memory)
  45         {
  46                 if (memory != null && !memory.getDefinition().equals(definition))
  47                         throw new IllegalArgumentException("Memory of incorrect memory definition given");
  48                 if (this.memory != null)
  49                         this.memory.registerObserver(memObs);
  50                 this.memory = memory;
  51                 if (memory != null)
  52                         memory.registerObserver(memObs);
  53                 update();
  54         }
  55
  56         public MicroInstructionMemory getMemory()
  57         {
  58                 return memory;
  59         }
  60
  61         @Override
  62         public List<ReadEnd> getAllInputs()
  63         {
  64                 return List.of(address);
  65         }
  66
  67         @Override
  68         public List<ReadWriteEnd> getAllOutputs()
  69         {
  70                 return List.of(data);
  71         }
  72
  73         @Override
  74         protected TimelineEventHandler compute()
  75         {
  76                 if (memory == null || !address.getValues().isBinary())
  77                         return e -> data.feedSignals(Bit.U.toVector(data.width()));// TODO don't always feed U, but decide to feed X or U.
  78                 long addressed = address.getValues().getUnsignedValueLong();
  79                 BitVector storedData = memory.getCell(addressed).toBitVector();
  80                 return e -> data.feedSignals(storedData);
  81         }
  82 }