FW82801DB S L66K Intel, FW82801DB S L66K Datasheet - Page 484

• Manufacturer Part Number: FW82801DB S L66K
• Manufacturer: Intel

Specifications of FW82801DB S L66K

• Lead Free Status / RoHS Status: Supplier Unconfirmed

AC ’97 Audio Controller Registers (D31:F5)
14.2.4
484
x_SR—Status Register
I/O Address:
Default Value:
Lockable:
Software can read the registers at offsets 04h, 05h, and 06h simultaneously by performing a single,
32-bit read from address offset 04h. Software can also read this register individually by doing a
single, 16-bit read to offset 06h. Reads across DWord boundaries are not supported.
15:5
Bit
4
3
2
1
0
Reserved.
FIFO Error (FIFOE) — R/WC.
0 = Software clears this bit by writing a 1 to this bit position.
1 = FIFO error occurs.
The ICH4 will set the FIFOE bit if the under-run or overrun occurs when there are more valid buffers
to process.
Buffer Completion Interrupt Status (BCIS) — R/WC.
0 = Software clears this bit by writing a 1 to this bit position.
1 = Set by the hardware after the last sample of a buffer has been processed, AND if the Interrupt
Last Valid Buffer Completion Interrupt (LVBCI) — R/WC.
0 = Software clears this bit by writing a 1 to this bit position.
1 = Last valid buffer has been processed. It remains active until cleared by software. This bit
Current Equals Last Valid (CELV) — RO.
0 = Cleared by hardware when controller exists state (i.e., until a new value is written to the LVI
1 = Current Index is equal to the value in the Last Valid Index Register, and the buffer pointed to by
DMA Controller Halted (DCH) — RO.
0 = Running.
1 = Halted. This could happen because of the Start/Stop bit being cleared and the DMA engines
on Completion (IOC) bit is set in the command byte of the buffer descriptor. It remains active
until cleared by software.
indicates the occurrence of the event signified by the last valid buffer being processed. Thus,
this is an event status bit that can be cleared by software once this event has been
recognized. This event will cause an interrupt if the enable bit in the Control Register is set.
The interrupt is cleared when the software clears this bit.
In the case of Transmits (PCM out, Modem out) this bit is set, after the last valid buffer has
been fetched (not after transmitting it). While in the case of Receives , this bit is set after the
data for the last buffer has been written to memory.
register.)
the CIV has been processed (i.e., after the last valid buffer has been processed). This bit is
very similar to bit 2, except this bit reflects the state rather than the event. This bit reflects the
state of the controller, and remains set until the controller exits this state.
are idle, or it could happen once the controller has processed the last valid buffer.
• PISR Register: FIFO error indicates a FIFO overrun. The FIFO pointers do not
• POSR Register: FIFO error indicates a FIFO underrun. The sample transmitted in this
NABMBAR + 06h (PISR),
NABMBAR + 16h (POSR),
NABMBAR + 26h (MCSR)
MBBAR + 46h (MC2SR)
MBBAR + 56h (PI2SR)
MBBAR + 66h (SPSR)
0001h
No
increment, the incoming data is not written into the FIFO, thus is lost.
case should be the last valid sample.
Description
Attribute:
Size:
Power Well:
Intel
R/WC, RO
16 bits
Core
®
82801DB ICH4 Datasheet