34 lines
1.1 KiB
Python
34 lines
1.1 KiB
Python
#!/usr/bin/python
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class Caretaker:
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def __init__(self):
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self.objects=dict() # Create empty objects pool
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# Add registers to pool
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for reg in ["MAR","MDR", "PC", "MBR", "SP","LV","CPP","TOS","OPC","H"]:
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self.objects[reg]=0
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self.objects["RAM"]=None
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def __getitem__(self,key):
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if key=="MBRU": # If we ask for unsigned
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return(abs(self.objects["MBR"]))
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elif key== "MBR":
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if (self.objects[key]>>7)==1: # If it a negative number (2 complement)
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return(-((self.objects[key]-1)^0xFF)) # transforme bin negative number to python negative number
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else:
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return(self.objects[key])
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return(self.objects[key])
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def __setitem__(self,key,value):
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if key!="RAM":
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if value > (2**32) and key!="MBR" and key!="MBRU": # Check value fit in word
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print("Warning word overflow: value {} on register {}".format(value,key))
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value=value%(2**32) # Force to fit in word
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elif value > (2**8) and key=="MBR" and key=="MBRU": # Check value fit in byte
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print("Warning byte overflow: value {} on register {}".format(value,key))
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value=value%256 # Force to fit in byte
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self.objects[key]=value
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def items(self):
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return(self.objects.items())
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