135
Area 7: Area 7 is an area with address bits A26–A24 set to 111 and an address range of
H'7000000–H'7FFFFFF and H'F000000–H'FFFFFFF. Figure 8.10 shows a memory map of area 7.
Area 7 is allocated to external memory space when A27 is 0 and on-chip RAM space when A27 is
1. In external memory space, the bus width is 8 bits. The A23 and A22 bits are not output and the
shadow is in 4-Mbyte units. When external memory is accessed, the CS7 signal is valid.
The on-chip RAM space has a bus width of 32 bits. In the SH7032, the on-chip RAM capacity is 8
kbytes, so A23–A13 are ignored and the shadows are in 8-kbyte units. In the SH7034, the on-chip
RAM capacity is 4 kbytes, so A23–A12 are ignored and the shadows are in 4-kbyte units. During
on-chip RAM access, the CS7 signal is not valid.
H'7000000
H'7400000
H'7800000
H'7C00000
H'73FFFFF
H'77FFFFF
H'7BFFFFF
H'7FFFFFF
Shadow
Shadow
Shadow
Shadow
External
memory
space
(4 Mbytes)
H'F000000
H'FFFFFFF
Shadow
Shadow
Shadow
Shadow
Shadow
Shadow
H'FFFF000 (SH7034)
H'F000FFF (SH7034)
H'FFFE000 (SH7032)
H'F001FFF (SH7032)
Logical address
space
Logical address
space
Actual
space
Actual
space
8-bit space 32-bit space
• On-chip
RAM space
SH7032:
8 kbytes,
SH7034:
4 kbytes
• Valid
addresses
SH7032:
A12–A0
(A23–A13
not output)
SH7034:
A11–A0
(A23–A12
not output)
• CS7 not
valid
• Valid
addresses
A21–A0
(A23 and A22
not output)
• CS7 valid
Figure 8 10 Memory Map of Area 7
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