ucb1500 NXP Semiconductors, ucb1500 Datasheet - Page 22

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

Philips Semiconductors
9397 750 07443
Product specification
8.1.6 [0014-0015]: Transmit DMA #1 descriptor table pointer (DTP).
Table 27: Receive DMA #1 Command Register bit description
Bit
11(r)
10-9
8(r)
7
6
5(w)
4(w)
3
2(w)
1
0
•
•
[0014] lower 16-bit of DTP
[0015] higher 16-bit of DTP
Description
Receive DMA #1 DT full
This read-only bit is set whenever all the receive descriptors for DMA #1 have
been used, and the receive DMA is done. If descriptor table is setup as a circular
queue, this bit does not become set. Writing a ‘1’ to this register clears this
status bit.
Reserved.
Receive-DMA #1 active status
If set, DT of receive DMA #1 is currently receiving data.
Receive DMA #1 enable
Must be set to 1.
Reserved.
Receive DMA #1 clear abort
Setting this bit clears the receive abort condition. This also clears bit 12 of this
register.
Receive DMA #1 software abort
Setting this bit immediately aborts receive cycle and disables receive DMA #1.
This also causes bit 12 of this register to become set.
Reserved.
Start receive-DMA #1
Set this bit to 1 initiate DMA#1 receive mode after the receive descriptor tables
are setup.
HOLD status/acknowledge
If this bit is set upon a read access, the UCB1500 is currently in the hold
condition, as a result of reading an invalid descriptor entry, and is waiting for an
acknowledgment before proceeding. Writing a 1 to this bit will send a hold
acknowledge to the UCB1500.
Reserved.
Rev. 03 — 7 July 2000
PCI to AC97 bridge/host controller
…continued
© Philips Electronics N.V. 2000. All rights reserved.
UCB1500
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