Mumbai University > Electronics Engineering > Sem6 > Computer Organization

Marks: 10M

Year: Dec 2015

1) The control memory is a ROM with a capacity of five 12-bit microinstructions. Four of the output bits of ROM go to the datapath control inputs, while the remaining 8 bits determine the next address for the CAR.

2) The SEL bits control the 4:1 multiplexer MUX2. For SEL at 00, MUX2 select input 0, which has the value 0. 0 on S of MUX 1 selects NXTADD0 as the next address as shown in below table.

Table 1

3) For SEL at 01, MUX 2 select input 1, which is G. If G is 0, then the S on MUX 1 is 0, selecting NXTADD0 as the address; if G is 1, the address Becomes NXTADD1. The other two decision variables, Q0 and Z, operates in similar manner.

4) Figure below shows a chart for Microprogrammed Binary multiplier Control unit.