307013-003 Datasheet, PDF (651/848 Pages) Intel Corporation – Intel I/O Controller Hub 7

AC ’97 Modem Controller Registers (D30:F3) (Desktop and Mobile Only)
17.1.10 MMBAR—Modem Mixer Base Address Register
(Modem—D30:F3)
Address Offset: 10–13h
Default Value: 00000001h
Attribute:
Size:
R/W, RO
32 bits
The Native PCI Mode Modem uses PCI Base Address register #1 to request a
contiguous block of I/O space that is to be used for the Modem Mixer software
interface. The mixer requires 256 bytes of I/O space. All accesses to the mixer registers
are forwarded over the AC-link to the codec where the registers reside.
In the case of the split codec implementation accesses to the different codecs are
differentiated by the controller by using address offsets 00h–7Fh for the primary codec
and address offsets 80h–FEh for the secondary codec.
Bit
Description
31:16
15:8
7:1
0
Hardwired to 0’s.
Base Address — R/W. These bits are used in the I/O space decode of the Modem
interface registers. The number of upper bits that a device actually implements
depends on how much of the address space the device will respond to. For the AC ‘97
Modem, the upper 16 bits are hardwired to 0, while bits 15:8 are programmable. This
configuration yields a maximum I/O block size of 256 bytes for this base address.
Reserved. Read as 0
Resource Type Indicator (RTE) — RO. Hardwired to 1indicating a request for I/O space.
17.1.11 MBAR—Modem Base Address Register (Modem—D30:F3)
Address Offset: 14h–17h
Default Value: 00000001h
Attribute:
Size:
R/W, RO
32 bits
The Modem function uses PCI Base Address register #1 to request a contiguous block
of I/O space that is to be used for the Modem software interface. The Modem Bus
Mastering register space requires 128 bytes of I/O space. All Modem registers reside in
the controller, therefore cycles are not forwarded over the AC-link to the codec.
Bit
Description
31:16
15:7
6:1
0
Hardwired to 0’s.
Base Address — R/W. These bits are used in the I/O space decode of the Modem
interface registers. The number of upper bits that a device actually implements
depends on how much of the address space the device will respond to. For the AC ‘97
Modem, the upper 16 bits are hardwired to 0, while bits 15:7 are programmable. This
configuration yields a maximum I/O block size of 128 bytes for this base address.
Reserved. Read as 0
Resource Type Indicator (RTE) — RO. Hardwired to 1 indicating a request for I/O
space.
Intel ^® ICH7 Family Datasheet
651