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