--
l
EISA bus
Ethernet LAN Adapter
1.0 OVERVIEW
2.0 CONFIGURATION
2.1 EISA Configuration Port
ter uses 64 I/O locations. The I/O locations use the EISA
bus slo locations for non-conflict and are always at the same base
address. The user can configure the location of the shared memory
and configure the interrupt by writing to the Configuration Port.
There are no switches or
for setting the confi ration. The
Configuration Port is rea /write and is located at Oh, where
is the slot number. The port has the following bit definitions.
2.1.1
NETWORK INTERFACE CONTRDLLER
The
NIC contains 16 registers that are mapped at the start
of the I/O address range. The ran e for the NIC register is:
where is the EISA bus s ot number.
2.1.2 ETHERNET ADDRESS
The Ethernet address PROW ma be read at I/O location
where is
the EISA slot number.
2.2
ADDRESSES
The adapter's 32K of
is mapped into the upper address locations
by the confi
even though
uration port. The address granularity is 64K bytes,
he adapter contains 32K.
2.3 INTERRUPTS
interru t to
uest service
the
by t e DP839 and remains active
interrupts are configured by the
interrupts are
3, 5, 7, 9,
2.4 NETWORK SELECTION
can be configured to operate an Ethernet Thick,
(Thin,
or Twisted
RJ4 ) network.
the adapter for Ethernet enables the
shell
Unit Interface connector. Configurin the ter
for
Cheapernet enables the BNC connector for connec
ion to t e network.
Configurin
for connec
the
ter for Twisted pair enables the RJ45 connector
ion to t e network.
one configuration at a time is
possible and is selected through E SA configuration.
3.0
DP8390 REGISTER ACCESSES
PC until the NIC leaves master mode.
3.1 REGISTER ACCESS DESCRIPTION
All NIC internal
isters are 8bits wide. The PC address lines
are
o the
NIC
and select the internal register
during the access. For the Ethernet address/ID
no wait states
are ever inserted.
4.0
ACCESSES
Data is moved to and
the adapter with shared memory accesses
by the system. Only doubleword aligned transfers are permitted.
5.0 PROGRAMMER'S REFERENCE
I/O
ADDRESS
(Note: I/O Base is determined by slot adapter is inserted.)
Base
Slot
Number
4000h
5000h
800011
REGISTER HAP
Address
Function
I/O Base Oh
I/O Base +
lh
Base Register
Register)
I/O Base 2h
Register 1
Register 2
I/O Base
Register F
I/O Base
16h
I/O Base
17h
Ethernet Address Byte 0
I/O Base
18h
Ethernet Address Byte 1
I/O Base
Ethernet Address Byte 2
I/O Base
Address Byte 3
I/O Base
Address
4
Ethernet Address Byte 5
