hd64338023s Renesas Electronics Corporation., hd64338023s Datasheet - Page 73

• Manufacturer Part Number: hd64338023s
• Description: Renesas 8-bit Single-chip Microcomputer Super Low Power Series
• Manufacturer: Renesas Electronics Corporation.

2.3.2
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.
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.
Byte data (CCR) on stack
Memory Data Formats
Note: * Ignored on return
[Legend]
CCR: Condition code register
Word data on stack
Data Type
Word data
Byte data
1-bit data
Figure 2.4 Memory Data Formats
Even address
Even address
Even address
Odd address
Odd address
Odd address
Address
Address n
Address n
MSB
MSB
MSB
MSB
MSB
7
7
Rev. 7.00 Mar 10, 2005 page 31 of 652
6
5
Data Format
Upper 8 bits
Lower 8 bits
4
CCR *
CCR
3
2
REJ09B0042-0700
1
Section 2 CPU
LSB
LSB
LSB
LSB
LSB
0
0