Misaligned Word Accessing (Little-Endian) - NEC uPD98502 User Manual

The following special instructions to load and store data that are not aligned on 4-byte (word) or 8-byte
(doubleword) boundaries:
LWL
LDL
These instructions are used in pairs to provide an access to misaligned data. Accessing misaligned data incurs
one additional instruction cycle over that required for accessing aligned data.
Figure 2-6 shows the access of a misaligned word that has byte address 3 for the little-endian conventions.
High-order
address
Low-order
address
62
CHAPTER 2 V
LWR
LDR
Figure 2-6. Misaligned Word Accessing (Little-Endian)
31 24 23
3
Preliminary User's Manual S15543EJ1V0UM
4120A
R
SWL
SDL
16 15 8 7
6 5
SWR
SDR
0
4