6.3.4. Instruction Unit 6: Hardwired Control Unit

Try these first

1. 1.

   What is a control unit?

   Hint

   Think about which part of the computer directs operations.

2. 2.

   Define a macro instruction.

   Hint

   Try remembering the difference between high-level and low-level instructions.

3. 3.

   What defines a hardwired control unit?

   • Fixed logic circuits
   • Software-based system
   • Dynamic programming

   Hint

   Think about how this system produces its signals.

4. 4.

   True or False: A micro instruction can operate independently of a macro instruction.

   • True
   • False

   Hint

   Reflect on how instructions are nested.

5. 5.

   Design a control signal sequence for a given macro instruction to increment a counter in memory.

   Hint

   Think about each step needed to modify the memory.

6. 6.

   Compare and contrast the advantages of hardwired versus microprogrammed control units in specific applications.

   Hint

   Factor in the complexity of the tasks each type processes.