Components:
PC - Program Counter - Stores current point of execution
Inputs:
Input - New PC to be stored is input here, 16 bits

Outputs:
Output - Existing PC is output here, 16 bits

Controls:
Write - Determines if PCInput should be stored, 1 bit
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Memory - Memory Controller - Reads and writes memory
Inputs:
Address - Address at which memory should be read, 16 bits

Outputs:
Data - Memory at given address, 16 bits

Controls:
Read - Determines if controller should use new incoming address, 1 bit
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IR - Instruction Register - Stores current instruction and splits into constitutent parts
Inputs:
Input - Takes incoming instruction, 16 bits

Outputs:
Opcode - Outputs opcode (IR[15-12]), 4 bits
RegisterA - Outputs number of reg. A (IR[11-8]), 4 bits
RegisterB - Outputs number of reg. B (IR[7-4]), 4 bits
Offset - Outputs offset or immediate (IR[7-0]), 8 bits

Controls:
Write - Determines if new instruction should be read, 1 bit
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A - Register A Storage
Inputs:
Input - Takes contents of register A for storage, 16 bits

Outputs:
Output - Returns stored value of A, 16 bits

Controls:
-
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B - Register B Storage
Inputs:
Input - Takes contents of register B for storage, 16 bits

Outputs:
Output - Returns stored value of B, 16 bits

Controls:
-
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C
Inputs:
Input - Takes results from adder, 16 bits

Outputs:
Output - Returns stored value of C, 16 bits

Controls:
-
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IEB - Interrupt Enable Bit - Determines if we ignore interrupts
Inputs:
Input - IEB value to be stored, 1 bit

Outputs:
Output - Current IEB value, 1 bit

Controls:
Write - Determines if we write incoming IEB value, 1 bit
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not - Inverter
Inputs:
Input - Value to be inverted, 1 bit

Outputs:
Output - Inverted value, 1 bit

Controls:
-
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EPC - Exception Program Counter - Saves PC during exception/interrupt
Inputs:
Input - Stores an incoming PC, 16 bits

Outputs:
Output - Returns a stored PC, 16 bits

Controls:
Write - Determines if a new incoming PC should be stored
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Sign Extend
Inputs:
Input - 8 bits

Outputs:
Output - Returns input with sign extended, 16 bits

Controls:
-
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Shift Left 1
Inputs:
Input - 16 bits

Outputs:
Output - Returns input with all bits shifted left once,
	 and left-most bit discarded, 16 bits
	 
Controls:
-
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Shift Left 8
Inputs:
Input - 16 bits

Outputs:
Output - Returns input with all bits shifted left eight times,
	 and left-most eight bits discarded, 16 bits
	 
Controls:
-
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Shift Right 15
Inputs:
Input - 16 bits

Outputs:
Output - Returns input with all bits shifted right 15 times,
	 and right-most 15 bits discarded, 16 bits
	 
Controls:
-
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ALU
Inputs:
InputA - Argument A of the adder, 16 bits
InputB - Argument B of the adder, 16 bits

Outputs:
Output - Returns the sum or difference of A and B, 16 bits
Zero - Returns whether the result was zero, 1 bit
	 
Controls:
Operation - Decides whether to take the sum or difference of A and B