Microprogramming: History and Evolution - Edwardbosworth.com
Microprogramming: History and Evolution - Edwardbosworth.com
Microprogramming: History and Evolution - Edwardbosworth.com
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The Microprogrammed Control Unit<br />
In a microprogrammed control unit, the control signals correspond to bits in a<br />
micromemory (CROM for Control ROM), which are read into a micro–MBR. This<br />
register is just a set of D flip–flops, the contents of which are emitted as signals.<br />
The micro–control unit ( CU )<br />
1) places an address into the micro–Memory Address Register ( MAR ),<br />
2) the control word is read from the Control Read–Only Memory,<br />
3) puts the microcode word into the micro–Memory Buffer Register, <strong>and</strong><br />
4) the control signals are issued.