Objective of this lab:

	To study the operation of an 8-bit CPU and control unit. 

Preparation

	Read lab lecture notes and the material in this page.

Lab Assignments

Please submit Lab4.pdf inculding the following:

1. Open your 8-bit CPU working circuit file

   
   	Do the following operations: 
       
   	1.	load the number 8 into memory location 5 
   
   	2.	move (the contents in) memory location 5 to the PC 
   
   	3.	increment the PC 
         
          
         Write down the microinstructions to hand-in:
   
           ________________________________
   
           ________________________________
   
           ________________________________
   
           ________________________________
   
   

2. Execute the following program (Hand in)

   
   a).	Write out the equivalent assembly language mnemonics of the following 
   	machine language code:
     
   	
   
         Location 	Contents 	Assembly Language Mnemonics 
         =============================================================
         0 	10000001  
         -------------------------------------------------------------
         1 	00010110  
         -------------------------------------------------------------
         2 	00000101  
         -------------------------------------------------------------
         3 	00001000  
         -------------------------------------------------------------
   
   	
   
   b).	Load the above program (in machine code) to the memory. 
   
   c).     Pre-load value 1 in the B register, preload 0 in the memory location 8. 
   
   d).  	Write out the microinstructions necessary to execute the program. 
   
           To execute the program, make sure the PC points to the beginning of the program. 
   
           Hand in the procedures used in the different steps including
   	the equivalent assembly language mnemonics and microinstructions 
   	needed for pre-loading and execution of the program.  
   
   

3. Implement the following tasks with your 8-bit CPU circuit, remember to pre-load the registers or memory when needed:

   
           1) Write out and hand in the microinstructions to perform this operation
   
              XOR #5,(C)
              including the machine code and how you load it to the memory.
   
              Pre-load the registers or memory when needed.
              For example:  Load 00001000  to the C register
                            Load 00000000  to the memory location 8
   
           2) Write out and hand in the microinstructions to perform the operation
   
              OR 5, 8
              including the machine code and how you load it to the memory.
   
              Pre-load the registers or memory when needed.
              For example:  Load 00001010  to the memory location 5
                            Load 00000000  to the memory location 8