Assembly language that corresponds to machine instruction in MIPS
I believe it is a bitwise and immediate AND.

You had the first two steps right:

OX3062FF80
0011 0000 0110 0010 1111 1111 1000 0000


But not the rest.

First separate out the opcode, starting from the left.  All opcodes are 6 bits.

So the opcode in binary, from the left, is:

001100


which is 0xC.  This is an andi instruction.

Then you need to separate out the fields according to the MIPS I instruction format;

001100  00011  00010  1111 1111 1000 0000 

opcode    rs    rt        immediate

Opcode:     0xC
rs:         0x03
rt:         0x02
Immediate:  0xFF80


I wrote some code and checked that an adi instruction has the above format in a disassembly listing.

To convert this into a assembly instruction:

The assembly language format of an andi is:

andi,rs,rt,IMM


Looking up the MIPS registers for the rs and rt fields:

rs = 0x03 =&gt; $v1
rt = 0x02 =&gt; $v0


so the corresponding assembly instruction is:

andi  $v1,$v0,0xFF80