ext.md

EXT - Sign-extend a data register

Operation

[destination] ← sign-extended[destination]

Syntax

EXT.W Dn
EXT.L Dn

Attributes

Size word, longword

Description

Extend the least-significant byte in a data register to a word, or extend the least-significant word in a data register to a longword. If the operation is word sized, bit 7 of the designated data register is copied to bits (8:15). If the operation is longword sized, bit 15 is copied to bits (16:31).

Application

If [D0] = $12345678, EXT.W D0 results in 12340078₁₆
If [D0] = $12345678, EXT.L D0 results in 00005678₁₆

Condition codes

X	N	Z	V	C
-	*	*	0	0

From MOTOROLA M68000 FAMILY Programmer's reference manual. Copyright 1992 by Motorola Inc./NXP. Adapted with permission.