Subroutines

Lecture 13: Subroutines

222 Questions172 MCQs45 Short Questions5 Long Questions

Showing 221 – 222 of 222 Questions

Page 23 of 23

Q221📝 Short Q📑 Lec 5Easy⭐High-Yield💡Conceptual

What is the Direction Flag (DF) in 8086 assembly language, and how does it control string manipulation processing?

💻 assembly Snippet

; Setting Direction Flag for String Processing
cld    ; Clear DF (DF = 0): Auto-increment mode (left to right)
std    ; Set DF (DF = 1): Auto-decrement mode (right to left)

Q222📝 Short Q📑 Lec 5Medium⭐High-Yield💡Conceptual

What are the Source Index (SI) and Destination Index (DI) registers in 8086 assembly language, and how do their default segment associations operate?

💻 assembly Snippet

; Block copy using SI and DI registers
mov si, src_offset ; Source offset relative to DS
mov di, dst_offset ; Destination offset relative to ES
cld                ; Clear direction flag (auto-increment)
movsb              ; Copy byte from [DS:SI] to [ES:DI]

Subroutines

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