# CO-Test 2-Question 14

```A machine has a 32-bit architecture, with two-word long instructions. It has 4200
General Purpose Registers and 1048 Special Purpose Registers, each of which is
32 bits long. It needs to support 1880 instructions, which have an immediate
operand in addition to two General Purpose Register operands and one Special
Purpose Register operand. Assuming that the immediate operand is represented
in 2’s complement integer format, the maximum positive value of the immediate
operand is:—```
reshown Oct 13, 2018

Instruction format : 32 bit architechture with 2 word long instruction. = 64 bit

#f opcodes = 1880 = 2^11 = 11 bits.

#f General Purposes registers = 4200 = 2^13 = 13 bits.

#f Special Purpose Registers = 1048 = 2^11 = 11 bits.

 opcodes GPR1 GPR2 SPR immediate 11bit 13bit 13bit 11bits ?

Let immediate operand = x

11+11+13+13+x=64

x= 64-48=16 bits.

The 2's complement integer (-2^n-1 to 2^n-1 -1)

n = 16

the maximum value = 2^15-1=32767.

answered Oct 16, 2018 by (3,730 points)