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4-8
MPC8240 Integrated Processor User's Manual
MOTOROLA
Address Map B
Notes
1. This address range is separately programmable (see Section 5.8, òAddress Map B Options Registeró) for the
processor interface and the PCI interface to control whether accesses to this address range go to system
memory or PCI memory.
2. The MPC8240 generates a memory select error (if enabled; see Section 5.7.2, òError Enabling Registersó) for
transactions in the address range 4000_0000D7FFF_FFFF. If memory select errors are disabled, the MPC8240
returns all 1s for read operations and no update for write operations.
3. If AMBOR[CPU_FD_ALIAS_EN] = 1 (see Section 5.8, òAddress Map B Options Registeró), the MPC8240
forwards processor transactions in this range to the zero-based PCI memory space with the 8 most signiTcant
bits cleared (that is, AD[31D0] = 0x00 || A[8D31] of the internal peripheral logic address bus).
4. Processor addresses are translated to PCI addresses as follows:
PCI address (AD[31D0]) = 0x00 || A[8D31] to generate an address range 0000_0000D007F_FFFF. Note that the
processor address range FE01_0000DFE7F_FFFF is reserved for future use.
5. The MPC8240 forwards processor transactions in this range to the PCI I/O space with the 8 most signiTcant
bits cleared (that is, AD[31D0] = 0x00 || A[8D31]).
6. Each word in this address range is aliased to the PCI CONFIG_ADDR register. See Section 5.1.2, òProcessor
Access to ConTguration Registers (Map B).ó
7. Each word in this address range is aliased to the PCI CONFIG_DATA register. See Section 5.1.2, òProcessor
Access to ConTguration Registers (Map B).ó
8. The processor and PCI masters can access ROM/Flash on the local bus in the address range 0xFF00_0000 -
0xFF7F_FFFF if the ROM/Flash is conTgured to be on the local bus at reset or if PIRC2[CF_FF0_LOCAL] = 1
(see Section 5.6, òProcessor Interface ConTguration Registersó); otherwise, the address is sent to PCI. This
address range will always be treated as an access to a 32-bit or 64-bit wide device as conTgured at reset if it is
conTgured to be on the local bus.
9. The processor and PCI masters can access ROM/Flash on the local bus in the address range 0xFF70_0000 -
0xFFFF_FFFF if the ROM/Flash is conTgured to be on the local bus at reset (see Section 5.6, òProcessor
Interface ConTguration Registersó); otherwise, the address is sent to PCI. This address range will be treated as
an access to a 8-bit, 32-bit or 64-bit wide device as conTgured at reset if it is conTgured to be on the local bus.
10. If AMBOR[PCI_FD_ALIAS_EN] = 1 (see Section 5.8, òAddress Map B Options Registeró), the MPC8240
forwards PCI memory transactions in this range to local memory with the 8 most signiTcant bits cleared (that is,
0x00 || AD[23D0]).
Table 4-7. Address Map BPCI I/O Master View
PCI I/O Transaction Address Range
Processor Core
Address Range
DeTnition
Hex
Decimal
0000_0000
0000_FFFF
0
64K D 1
No system memory cycle
PCI/ISA I/O space
0001_0000
007F_FFFF
64K
8M D 1
No system memory cycle
Reserved
0080_0000
00BF_FFFF
8M
12M D 1
No system memory cycle
PCI I/O space
00C0_0000
FFFF_FFFF
12M
4G D 1
No system memory cycle
Reserved