am79c970 Advanced Micro Devices, am79c970 Datasheet - Page 2

• Manufacturer Part Number: am79c970
• Description: Pcnettm-pci Single-chip Ethernet Controller For Pci Local Bus
• Manufacturer: Advanced Micro Devices

controllers in the PCnet Family, including the PCnet-ISA
controller (Am79C960), the PCnet-ISA
(Am79C961),
(Am79C965). The buffer management unit supports the
LANCE, ILACC, and PCnet descriptor software models.
The PCnet-PCI controller is software compatible with
the Novell NE2100 and NE1500 Ethernet adapter card
architectures. In addition, a Sleep function has been in-
corporated to provide low standby current, excellent for
notebooks and Green PCs.
The 32-bit multiplexed bus interface unit provides a di-
rect interface to the PCI local bus applications, simplify-
ing the design of an Ethernet node in a PC system. With
its built-in support for both little and big endian byte
alignment, this controller also addresses proprietary
non-PC applications.
The PCnet-PCI controller supports auto configuration in
the PCI configuration space. Additional PCnet-PCI
BLOCK DIAGRAM
AD[31:00]
C/BE[3:0]
DEVSEL
FRAME
IDSEL
NOUT
LOCK
PERR
SERR
TRDY
STOP
IRDY
INTA
CLK
REQ
PAR
GNT
RST
and
the
Management
Interface
PCI Bus
PCnet-32
Buffer
Unit
Unit
+
controller
controller
P R E L I M I N A R Y
Am79C970
Control
FIFO
FIFO
Rcv
Xmt
FIFO
controller configuration parameters, including the
unique IEEE physical address, can be read from an ex-
ternal non-volatile memory (serial EEPROM) immedi-
ately following system RESET.
The controller also has the capability to automatically
select either the AUI port or the Twisted-Pair trans-
ceiver. Only one interface is active at any one time. The
individual transmit and receive FIFOs optimize system
overhead, providing sufficient latency during frame
transmission and reception, and minimizing intervention
during normal network error recovery. The integrated
Manchester encoder/decoder (MENDEC) eliminates
the need for an external Serial Interface Adapter (SIA) in
the system. In addition, the device provides program-
mable on-chip LED drivers for transmit, receive, colli-
sion, receive polarity, link integrity or jabber status.
Manchester
Microwire
and LED
Encoder/
Decoder
AUI Port
(PLS) &
802.3
Control
MAC
Core
10BASE-T
MAU
CI+/-
DI+/-
XTAL1
XTAL2
RXD+/-
TXD+/-
TXP+/-
LNKST/EEDI
DO+/-
EECS
EESK/LED1
EEDO/LED3
AMD
18220C-1
1-869