HD6473847RHV Datasheet, PDF (70/546 Pages) Renesas Technology Corp – Renesas 8-Bit Single-Chip Microcomputer H8 Family / H8/300L Super Low Power Series

Section 2 CPU
2.4.2 Memory Data Formats
Figure 2.5 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 Type
Address
Data Format
1-bit data Address n
7
0
76543210
Byte data Address n _MSB
LSB
Even address MSB
Upper 8 bits
Word data
Odd address
Lower 8 bits
LSB
Even address MSB
CCR
LSB
Byte data (CCR) on stack
Odd address MSB
CCR*
LSB
Even address MSB
Word data on stack
Odd address
LSB
Note: * Ignored on return
Legend:
CCR: Condition code register
Figure 2.5 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.
Rev. 7.00 Mar. 08, 2010 Page 38 of 510
REJ09B0024-0700