AM79C976 Advanced Micro Devices, AM79C976 Datasheet - Page 128
![no-image](/images/manufacturer_photos/0/0/14/advanced_micro_devices_sml.jpg)
AM79C976
Manufacturer Part Number
AM79C976
Description
PCnet-PRO 10/100 Mbps PCI Ethernet Controller
Manufacturer
Advanced Micro Devices
Datasheet
1.AM79C976.pdf
(309 pages)
- Current page: 128 of 309
- Download datasheet (3Mb)
AUTOPOLL5:
Offset 092h
This register controls the automatic polling of a user-
selectable external PHY register, AP_REG5.
Offset 120h
This 64-bit register allows the Receive Descriptor Ring
to be located anywhere in a 64-bit address space. For
systems with a 32-bit or smaller address space, it is
only necessary to program the lower 32 bits of this reg-
128
14-13
12-8
63-0
Bit
4-0
Bit
15
7
6
5
AP_REG5_ADDR
AP_PHY5_ADDR
AP_PHY5_DFLT
AP_PRE_SUP5
AP_REG5_EN
BADR
Name
Auto-Poll5 Register
Name
RES
RES
Base Address of Receive Descriptor Ring. In systems with a 32-bit or smaller address space, it is
only necessary to program the 32 low-order bits of this register.
The low order 32 bits of this register are an alias of CSR24 and CSR25.
Enable Bit for Autopoll Register 5. When this bit and the Auto-Poll External PHY bit (APEP) in
CMD1 are both set to 1, the Auto-Poll State Machine periodically reads the external PHY register
selected by the AP_PHY5_ADDR and AP_REG5_ADDR fields and sets the APINT5 interrupt bit
if it detects a change in the register’s contents.
Reserved locations. Written as zeros and read as undefined.
AP_REG5 Address. This field contains the register number of an external PHY register that the
Auto-Poll State Machine will periodically read if the AP_REG5_EN bit in this register and the
APEP bit (CMD3, bit 24) is set.
Reserved location. Written as zero and read as undefined.
Auto-Poll Preamble Suppression. If this bit is set to 1, the Auto-Poll State Machine will suppress
the preambles of the MII Management Frames that it uses to periodically read the external PHY
register selected by the AP_PHY5_ADDR and AP_REG5_ADDR fields.
This bit is ignored when the AP_PHY5_DFLT bit is set.
Auto-Poll PHY5 Default. When this bit is set, the Auto-Poll State Machine ignores the contents of
the AP_PHY5_ADDR and AP_PRE_SUP5 fields and uses the AP_PHY0_ADDR field for the
address of the PHY device to be polled. If this bit is set, the Auto-Poll State Machine will suppress
preambles only if the Port Manager has determined that the default external PHY can accept MII
Management Frames without preambles. (The Port Manager examines bit 6 in register 1 of the
default PHY to make this determination.)
Auto-Poll PHY5 Address. This field contains the address of the external PHY that contains
AP_REG5.
This bit is ignored when the AP_PHY5_DFLT bit is set.
Table 37.
Table 38.
P R E L I M I N A R Y
Receive Ring Base Address Register
AUTOPOLL5: Auto-Poll5 Register
Am79C976
All bits in this register are set to their default values by
H_RESET. All bits are also set to their default values
before EEPROM data are loaded or after an EEPROM
read failure.
The default value for all bits in this register is 0.
ister (by writing to offset 120h). The upper 32 bits will
remain at the default value of 0.
The contents of this register are set to the default value
0 when the RST pin is asserted. This register is not af-
fected by the serial EEPROM read operation or by a se-
rial EEPROM read error.
Description
Description
8/01/00
Related parts for AM79C976
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![AM27S29DC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Advanced Micro Devices [4,096-Bit (512x8) Bipolar PROM]
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM27S29APC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Advanced Micro Devices [4,096-Bit (512x8) Bipolar PROM]
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM29BL802CB-70RZE](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Advanced Micro Devices [8 Megabit (512 K x 16-Bit) CMOS 3.0 Volt-only Burst Mode Flash Memory]
Manufacturer:
Advanced Micro Devices
Datasheet:
![M41000001Y](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
M41000001YAdvanced Micro Devices [32 Megabit (4 M x 8-Bit/2 M x 16-Bit) CMOS 3.0 Volt-only, Simultaneous Operation Flash Memory and 4 Mbit (512 K x 8-Bit/256 K x 16-Bit) Static RAM]
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM95C94JC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Advanced Burst Error Processor
Manufacturer:
Advanced Micro Devices
![AM7992BPC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Serial interface adapter (SIA)
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM9519ADC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Universal interrupt controller
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM27C256-150DC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
256 kilobit CMOS EPROM
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM9128-10PC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
2048 x 8 static RAM, 100ns
Manufacturer:
Advanced Micro Devices
Datasheet:
![P8284A](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Manufacturer:
Advanced Micro Devices
Datasheet:
![DM81LS98N](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Three-State Octal Buffers
Manufacturer:
Advanced Micro Devices
Datasheet:
![AM2966PC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
AM2966PCOctal Dynamic Memory Drivers with Three-State Outputs
Manufacturer:
Advanced Micro Devices
Datasheet:
![DM81LS97N](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Three-State Octal Buffers
Manufacturer:
Advanced Micro Devices
Datasheet:
![DM81LS96N](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
Three-State Octal Buffers
Manufacturer:
Advanced Micro Devices
Datasheet:
![PAL16L8-7PC](/images/manufacturer_photos/0/0/14/advanced_micro_devices_tmb.jpg)
Part Number:
Description:
TTL programmable array logic, 7ns
Manufacturer:
Advanced Micro Devices
Datasheet: