my idea to resolve JMP in CPU

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my idea to resolve JMP in CPU

osma78
 Hi ,
 My idea to create a CHIP that output a bit to a load of a PC is to combine two truth table the first is the truth table of a JUMP bit of a C-Instruction , the second is of the zr and ng bits output of UAL , i locate when these combination output one , my question is "is this the correct reasoning ?" , "is there another solution easier than these ?" , my problem with my solution is that i get a very long boolean logic function whose simplification is very difficult , i need a help to terminate the CPU .
Thank you .
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Re: my idea to resolve JMP in CPU

ivant
Reading Figure 4.5 we can see that a jump should occur if:
  • this is a C instruction
  • AND
    • j1 is set AND the result is negative
    • OR j2 is set and the result is zero
    • OR j3 is set and the result is positive
How can you tell if the instruction is C? How can you tell if the result is negative, zero or positive? Can you combine these things directly instead of using the truth tables?
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Re: my idea to resolve JMP in CPU

osma78
Thank you for your help , u have terminate a CPu successfully , and a ll the computer Hardware .