User`s guide

1.3 EB140A–TX Description
The EB140A–TX is based on the 21140A with direct connections to the PCI bus
and the 10Mb/s Ethernet and 100Mb/s Fast Ethernet networks. The evaluation
board is fully compliant with the PCI local bus specification, revisions 2.0 and
2.1, and is capable of PCI bus master operations working with programmable
burst length. The EB140A–TX uses INTA as the primary interrupt line.
The EB140A–TX uses a 5-volt to 3.3-volt regulator to supply power for
the 21140A. This enables the EB140A–TX to operate in systems that have only
a 5-volt power supply. The EB140A–TX can operate in PCI systems with either
a 5-volt or 3.3-volt signaling environment.
The evaluation board also provides full support for an upgradeable
boot ROM (64KB to 256KB).
Figure 1–1 shows the main components of the EB140A–TX.
Figure 1–1 Main Components of the EB140A–TX
LJ-04833.AI5
RJ45
10BASE-T
and
100BASE-TX
PHY
Chipset
Digital
Semiconductor 
21140A
PCI Fast Ethernet
LAN Controller
Boot
ROM
Boot
ROM
Port
Link LED
Transmit and
Receive LEDs
PCI
MII
Serial
ROM
Serial
ROM
Port
Preliminary—Subject to Change—July 1996 1–3