I'm trying to understand this code

MOV EAX,12345678h
ROR EAX,4

and what will the value of EAX be now ??

Acid_Cool_178

ROR (Rotate Right) by 4 (Bits)

12345678 -> 01234567

ROR - Rotate Right
Usage: ROR dest,count
Modifies flags: CF OF
.---------------. .-.
.->|7 ----------> 0|--.->|C|
| '---------------' | '-'
'---------------------'
Rotates the bits in the destination to the right "count" times with
all data pushed out the right side re-entering on the left. The
Carry Flag will contain the value of the last bit rotated out.

Clocks Size
Operands 808x 286 386 486 Bytes
reg,1 2 2 3 3 2
mem,1 15+EA 7 7 4 2-4 (W88=23+EA)
reg,CL 8+4n 5+n 3 3 2

mem,CL 20+EA+4n 8+n 7 4 2-4 (W88=28+EA+4n)
reg,immed8 - 5+n 3 2 3
mem,immed8 - 8+n 7 4 3-5

D0 /1 ROR r/m8,1 Rotate 8 bits r/m8 right once
D2 /1 ROR r/m8,CL Rotate 8 bits r/m8 right CL times

C0 /1 ib ROR r/m8,imm8 Rotate 8 bits r/m16 right imm8 times
D1 /1 ROR r/m16,1 Rotate 16 bits r/m16 right once
D3 /1 ROR r/m16,CL Rotate 16 bits r/m16 right CL times
C1 /1 ib ROR r/m16,imm8 Rotate 16 bits r/m16 right imm8 times
D1 /1 ROR r/m32,1 Rotate 32 bits r/m32 right once

D3 /1 ROR r/m32,CL Rotate 32 bits r/m32 right CL times
C1 /1 ib ROR r/m32,imm8 Rotate 32 bits r/m32 right imm8 times

eax : 12345678 and after ror eax,4 eax : 81234567

Regards