44 lines
1.6 KiB
Python
44 lines
1.6 KiB
Python
#!/usr/bin/python
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from components.ram import Ram
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class Caretaker:
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def __init__(self,ramSize):
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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"]=Ram(self,ramSize)
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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] < 0:
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return(self.objects[key])
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elif self.objects[key]>>7==1: # If it a negative number (2 complement)
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return(-(self.objects[key]&0x7F))
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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 (-(2**7-1))>value and (key=="MBR" or key=="MBRU"):
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raise RuntimeError("Value {} cannot fit in MBR register (-2^7 minimum value)".format(value))
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elif value>(2**32-1) and (key!="MBR" and key!="MBRU"):
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raise RuntimeError("Value {} cannot fit in MBR register (2^32 minimum value)".format(value))
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# if key!="RAM":
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# if (value > (2**32) or value <(2**32)/2) 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) or value <126) and key=="MBR" or 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=abs(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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