Memory Data Formats; Figure 2.10 Memory Data Formats - Renesas H8S Series Hardware Manual

Section 2 CPU
2.5.2

Memory Data Formats

Figure 2.10 shows the data formats in memory. The H8S/2000 CPU can access word data and
longword data in memory, but word or longword data must begin at an even address. If an attempt
is made to access word or longword data at an odd address, no address error occurs but the least
significant bit of the address is regarded as 0, so the access starts at the preceding address. This
also applies to instruction fetches.
When SP (ER7) is used as an address register to access the stack, the operand size should be word
size or longword size.
Rev. 3.00 Jul. 14, 2005 Page 34 of 986
REJ09B0098-0300
Data Type Address
1-bit data Address L
Byte data Address L
Word data Address 2M
Address 2M + 1
Longword data Address 2N
Address 2N + 1
Address 2N + 2
Address 2N + 3

Figure 2.10 Memory Data Formats

Data Image
7
7 6 5 4 3 2 1
MSB
MSB
MSB
0
0
LSB
LSB
LSB