1. Microprograms (Ch7.1)

2. Implementation
Instruction Environment

3. Lower Level Work defined by enabling paths: [MBR] = [r0] + [r1]
ER0_B = 1 ER1_C = 1 CMBR = 1 F0,1,2 = 1, 1, 0

4. Multi Step
Work likely takes multiple steps

5. Choices Hardcoded logic Decode opcode
Combine with timer circuit to output correct signals

6. Choices
Microprogrammed:
Control unit is a computer inside a computer

7. Microprogramming
List of micro steps for each machine instruction held in ROM
Output control signals to "real" CPU

8. Microcode Patches
Microcode used in all x86 processors

9. Pros & Cons Hardcoded Microprogram Faster
Fixable:
Flexible: Can simulate instructions without hardware