ucb1500 NXP Semiconductors, ucb1500 Datasheet - Page 41

• Manufacturer Part Number: ucb1500
• Description: Pci To Ac97 Bridge/host Controller
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 07443
Product specification
8.6.22 [da]: Power-on flag (V
8.6.23 [db]: Scratch Register (V
Table 63: Power-on flag (V
Table 64: Scratch register bit description
V
Bit
8
7-0
Bit
15-0
aux
powered
Description
AC97 Reset
This bit controls the state of the AC97_RST pin (V
when RST is asserted, AC97_RST pin will be asserted. AC97_RST pin can also
be asserted by writing a “0” to this register bit, and de-asserted by writing a “1”.
Remark: AC97_RST can only be de-asserted by software, and never by
hardware.
Power-on flag
Not affected by PCI reset. Used as a signature to control access to power
management registers. Valid values for flag are:
If power-on flag is neither of these values, all PME Status and PME_EN registers
of Function 0 or 1 are invalid, and PME is not generated externally.
Description
Scratch register
Sticky, can be used for user-defined functions.
A5h: For Function 0 or 1, all write accesses to PME Status and PME_EN
registers of its PCI configuration space are allowed.
5Ah: (For testing only.) For Function 0 or 1, all write accesses to the
PME Status and PME_EN registers of its PCI configuration space shall be
ignored if either Function 0 or Function 1 is in D3 state.
Rev. 03 — 7 July 2000
aux
aux
aux
powered and sticky) / AC97 reset
powered and sticky) / AC97 reset register bit description
powered)
PCI to AC97 bridge/host controller
aux
© Philips Electronics N.V. 2000. All rights reserved.
powered). At power-up, or
UCB1500
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