dp83932c-20 National Semiconductor Corporation, dp83932c-20 Datasheet - Page 45

• Manufacturer Part Number: dp83932c-20
• Description: Mhz Sonictm Systems-oriented Network Interface Controller
• Manufacturer: National Semiconductor Corporation

NETWORK INTERFACE PINS
EXT
CD
CD
RX
RX
TX
TX
CRSo
CRSi
COLo
COLi
5 0 Bus Interface
5 2 PIN DESCRIPTION
I
O
Z
ECL
TP
b
a
b
a
b
a
Symbol
e
e
e
e
e
input
output
TRI-STATE inputs are TTL compatible
ECL-like drivers for interfacing to the Attachment
Unit Interface
Totem pole like drivers These drivers are driven ei-
ther high or low and are always driven Drive levels
are CMOS compatible
Driver
Type
ECL
ECL
TP
TP
Direction
(Continued)
O
O
O
O
I
I
I
I
I
I
I
External ENDEC Select Tying this pin to V
and allows an external ENDEC to be used Tying this pin to ground (EXT
the internal ENDEC This pin must be tied either to V
pin definitions for CRSo CRSi COLo COLi RXDo RXDi RXCo RXCi and TXCo TXCi
When EXT
is used
Collision
be unconnected when an external ENDEC is selected (EXT
Collision
should be unconnected when an external ENDEC is selected (EXT
Receive
should be unconnected when an external ENDEC is selected (EXT
Receive
should be unconnected when an external ENDEC is selected (EXT
Transmit
be unconnected when an external ENDEC is selected (EXT
Transmit
be unconnected when an external ENDEC is selected (EXT
Carrier Sense Output (CRSo) from the internal ENDEC (EXT
CRSo signal is internally connected between the ENDEC and MAC units It is asserted
on the first valid high-to-low transition in the receive data (RX
active 1 5 bit times after the last bit of data Although this signal is used internally by the
SONIC it is also provided as an output to the user
Carrier Sense Input (CRSi) from an external ENDEC (EXT
activated high when the external ENDEC detects valid data at its receive inputs
Collision Output (COLo) from the internal ENDEC (EXT
COLo signal is internally connected between the ENDEC and MAC units This signal
generates an active high signal when the 10 MHz collision signal from the transceiver is
detected Although this signal is used internally by the SONIC it is also provided as an
output to the user
Collision Detect Input (COLi) from an external ENDEC (EXT
activated from an external ENDEC when a collision is detected This pin is monitored
during transmissions from the beginning of the Start Of Frame Delimiter (SFD) to the
end of the packet At the end of transmission this signal is monitored by the SONIC for
CD heartbeat
TABLE 5-1 Pin Description
a
b
a
b
a
b
e
The negative differential receive data input from the transceiver This pin
The positive differential receive data input from the transceiver This pin
0 the first pin definition is used and when EXT
The negative differential collision input from the transceiver This pin
The positive differential collision input from the transceiver This pin should
The negative differential transmit output to the transceiver This pin should
The positive differential transmit output to the transceiver This pin should
45
TRI
OC
e
e
TRI-STATE drivers These pins are driven high low
or TRI-STATE Drive levels are CMOS compatible
These pins may also be inputs (depending on the
pin)
Open Collector type drivers These drivers are
TRI-STATE when inactive and are driven low when
active These pins may also be inputs (depending
on the pin) Pin names which contain a ‘‘ ’’ indicate
dual function pins
Description
CC
(EXT
CC
e
1) disables the internal ENDEC
or ground Note the alternate
e
e
e
e
e
e
0) When EXT
a b
1 the second pin definition
e
e
1) The CRSi signal is
1)
1)
1)
1) The COLi signal is
0) When EXT
) This signal remains
e
e
e
1)
1)
1)
e
0) enables
e
0 the
e
0 the