AM79C976 Advanced Micro Devices, AM79C976 Datasheet - Page 263

• Manufacturer Part Number: AM79C976
• Description: PCnet-PRO 10/100 Mbps PCI Ethernet Controller
• Manufacturer: Advanced Micro Devices

8/01/00
CSR76
CSR78
CSR80
CSR88~89
CSR116
CSR122
CSR124
CSR125
Register
8000--
4000--
2000--
1000--
RCVRL: RCV Descriptor Ring length
XMTRL: XMT Descriptor Ring length
FIFO threshold and DMA burst control (DEFAULT = 1400)
8000
4000
bits [13:12] = RCVFW, Receive FIFO Watermark
bits [11:10] = XMTSP, Transmit Start Point
bits [9:8] = XMTFW, Transmit FIFO Watermark
bits [7:0] = Reserved
Chip ID (Contents = v2628003; v = Version Number)
OnNow Power Mode Register
8000
4000
2000
1000
Advanced Feature Control
8000
4000
2000
1000
BMU Test Register (DEFAULT = 0000)
8000
4000
2000
1000
MAC Enhanced Configuration Control (DEFAULT = 603c
bits [15:8] = IPG, InterPacket Gap (Default=60xx, 96 bit times)
bits [8:0] = IFS1, InterFrame Space Part 1 (Default=xx3c, 60 bit times)
0000 Request DMA when 48 bytes are present
1000 Request DMA when 64 bytes are present
2000 Request DMA when 128 bytes are present
3000 Reserved
0000 Start transmission after 16 bytes have been written
0400 Start transmission after 64 bytes have been written
0800 Start transmission after 128 bytes have been written
0C00 Start transmission after the full packet has been written
0000 Start DMA when 16 write cycles can be made
0100 Start DMA when 64 write cycles can be made
0200 Start DMA when 128 write cycles can be made
0300 Start DMA when 256 write cycles can be made
Reserved
Reserved
--
--
--
--
--
--
--
--
--
--
--
--
0800
0400
0200
0100
0800
0400
0200
0100
0800
0400
0200
0100
0800
0400
0200
0100
P R E L I M I N A R Y
LCDET
PM_EN_OVR
LCMODE
--
--
--
--
--
--
--
--
--
--
--
--
Am79C976
SSIZE32
Contents
0080
0040
0020
0010
0080
0040
0020
0010
0080
0040
0020
0010
0080
0040
0020
0010
PMAT
EMPPLBA
MPMAT
MPPEN
--
--
--
--
--
--
--
--
SWSTYLE
SWSTYLE
SWSTYLE
SWSTYLE
0008
0004
0002
0001
0008
0004
0002
0001
0008
0004
0002
0001
0008
0004
0002
0001
RWU_DRIVER
RWU_GATE
RWU_POL
RST_POL
--
--
--
RCVALGN
RPA
--
--
--
SWSTYLE
SWSTYLE
SWSTYLE
SWSTYLE
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