ucb1500 NXP Semiconductors, ucb1500 Datasheet - Page 36

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

Philips Semiconductors
9397 750 07443
Product specification
8.6.9 [00c8]: AC97 command/GPIO control and status register
Table 54: AC97 command/GPIO control and status register bit description
Bit
15-14
13
12
11
10
9
8
7
6-0
Description
Command ID
Specifies 1 of 4 codec IDs for the AC-LINK register access commands.
Reserved.
Valid index data
Reads to this register will return a “1” if there is valid index data from the codec
connected to AC97 channel #0 in register CCh, bits[6-0]. Writing a “1” to this bit
will clear the status.
Reserved.
Valid status data
Reads to this register will return a “1” if there is valid read data from the codec
connected to AC97 channel #0 in register CAh. Writing a “1” to this bit will clear
the status.
AC97 command enable
Writing a 1 to this bit issues a command to the AC97 codec as specified in
bits[7-0] of this register on the next AC97 slot 1. Data for the write command is
specified in register CAh. On reads, this register will return “1” while write cycle is
in progress.
AC97 command
1 = read; 0 = write. This bit is output during AC97 slot 1 bit 19.
Reserved.
Command register index
Register index to use when generating register read/write command to AC97
codec. This data is output during AC97 slot 1, bits[18-12].
00 = Codec0
01 = Codec1
10 = Codec2
11 = Codec3
Rev. 03 — 7 July 2000
PCI to AC97 bridge/host controller
© Philips Electronics N.V. 2000. All rights reserved.
UCB1500
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