Renesas H8 Series Hardware Manual

Section 2 CPU
Rev. 7.00 Mar 10, 2005 page 31 of 652
REJ09B0042-0700
2.3.2 Memory Data Formats
Figure 2.4 indicates the data formats in memory. The H8/300L CPU can access word data stored
in memory (MOV.W instruction), but the word data must always begin at an even address. If word
data starting at an odd address is accessed, the least significant bit of the address is regarded as 0,
and the word data starting at the preceding address is accessed. The same applies to instruction
codes.
Data Format
76543210
AddressData Type
70
Address n
MSB LSB
MSB
LSB
Upper 8 bits
Lower 8 bits
MSB LSBCCR
CCR
*
MSB
LSB
MSB LSB
Address n
Even address
Odd address
Even address
Odd address
Even address
Odd address
1-bit data
Byte data
Word data
Byte data (CCR) on stack
Word data on stack
[Legend]
CCR: Condition code register
Note: * Ignored on return
Figure 2.4 Memory Data Formats
When the stack is accessed using R7 as an address register, word access should always be
performed. When the CCR is pushed on the stack, two identical copies of the CCR are pushed to
make a complete word. When they are restored, the lower byte is ignored.

Renesas H8 Series Specifications

General

Brand	Renesas
Model	H8 Series
Category	Computer Hardware
Language	English