EXT.W Dn Extend byte to word EXT.L Dn Extend word to long word EXTB.L Dn Extend byte to long word (68020+) Size = (Word, Long)
Extends a byte to a word, or a word to a long word in a data register by copying the sign bit through the upper bits. If the operation is from byte to word, bit 7 is copied to bits 8 through 15. If the operation is from word to long word, bit 15 is copied to bits 16 through 31. The EXTB copies bit 7 to bits 8 through 31.
----------------------------------------------------------------- |15 |14 |13 |12 |11 |10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |---|---|---|---|---|---|---|-----------|---|---|---|-----------| | 0 | 1 | 0 | 0 | 1 | 0 | 0 | OP-MODE | 0 | 0 | 0 | REGISTER | ----------------------------------------------------------------- "REGISTER" specifies a data register. OP-MODE 010->Extending from 8 bits to 16 bits. 011->Extending from 16 bits to 32 bits. 111->Extending from 8 bits to 32 bits.
X - Not affected N - Set if the result is negative. Cleared otherwise. Z - Set if the result is zero. Cleared otherwise. V - Always cleared C - Always cleared