ROR : Rotate Right without Carry: This instruction rotates the contents of destination operand to the bit-wise right either by one or by the count specified in register CL, excluding carry. The least significant bit is pushed into the carry flag and concurrently it is transferred into the most significant bit position at each operation. Remaining bits are shifted right by the particular positions. The SF, PF, and ZF flags are remain unchanged by the rotate operation. The operand might be a memory location or register but it can't be an immediate operand. Given figure described the operation. The destination operand might be a memory location or a register (except a segment register).
Figure : Execution of ROR Instruction