Question

Differentiate between hardwired control and microprogrammed control

Answer 1

HARDWIRED CONTROL UNIT

MICROPROGRAMMED CONTROL UNIT

The control unit whose control signals are generated by the hardware through a sequence of instructions is called a hardwired control unit.

The control unit whose control signals are generated by the data stored in control memory and constitute a program on the small scale is called a microprogrammed control unit

The control logic of a hardwired control is implemented with gates, flip flops, decoders etc.

The control logic of a micro-programmed control is the instructions that are stored in control memory to initiate the required sequence of microoperations.

Wiring changes are made in the hardwired control unit if there are any changes required in the design.

Changes in a microprogrammed control unit are done by updating the microprogram in control memory.

Hardwired control unit are faster and known to have complex structure.

Microprogrammed control unit is comparatively slow compared but are simple in structure.