82801BA Datasheet, PDF (406/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

AC’97 Audio Controller Registers (D31:F5)
13.2.5
13.2.6
x_PICB—Position In Current Buffer Register
I/O Address:
Default Value:
Lockable:
NABMBAR + 08h (PIPICB),
NABMBAR + 18h (POPICB),
NABMBAR + 28h (MCPICB)
0000h
No
Attribute:
Size:
Power Well:
RO (Word access only)
16 bits
Core
This register can be accessed only as a Word (16 bits).
Bit
Description
Position In Current Buffer[15:0]—RO. These bits represent the number of DWords remaining to
15:0
be processed in the current buffer; the number of samples not yet read from memory (in the case of
reads from memory) or not yet written to memory (in the case of writes to memory), irrespective of
the number of samples that have been transmitted/received across AC-link.
x_PIV—Prefetched Index Value Register
I/O Address:
Default Value:
Lockable:
NABMBAR + 0Ah (PIPIV),
NABMBAR + 1Ah (POPIV),
NABMBAR + 2Ah (MCPIV)
00h
No
Attribute:
Size:
Power Well:
RO
8 bits
Core
Bit
Description
7:5 Hardwired to 0.
4:0
Prefetched Index Value[4:0]—RO. These bits represent which buffer descriptor in the list has
been prefetched. The bits in this register are also modulo 32 and roll over after they reach 31.
13-12
82801BA ICH2 and 82801BAM ICH2-M Datasheet