DP83950BNU NSC [National Semiconductor], DP83950BNU Datasheet - Page 38

• Manufacturer Part Number: DP83950BNU
• Manufacturer: NSC [National Semiconductor]

Name
RA0
RA1
RA2
RA3
RA4
5 0 Functional Description
Pin
Programming
Function
BYPAS1
BYPAS2
EXPLL
BINV
resv
TABLE 5 1 Pin Definitions for Options in the Mode Load Operation (Continued)
Not Permitted
Effect When
External PLL
Active High
Bit is 0
Signals
Effect When
Internal PLL
Active Low
Required
(Continued)
Signals
Bit is 1
38
These configuration bits select which of the repeater ports
(numbers 2 to 13) are configured to use the on-chip internal
10BASE-T transceivers or the external transceiver interface The
external transceiver interface operates using AUI compatible
signal levels
BYPAS2
This selection determines whether the Inter-RIC signals IRE
ACTN ANYXN COLN and Management bus signal MCRS are
active high or low
If desired the RIC may be used with an external decoder this
configuration bit performs the selection
To ensure correct device operation this bit must be written with
a logic one during the mode load operation
0
0
1
1
BYPAS1
0
1
0
1
All ports (2 to 13) use the external
Transceiver Interface
Ports 2 to 7 use the external
interface 8 to 13 use the internal
10BASE-T transceivers
Ports 2 to 5 use the external
interface 6 to 13 use the internal
10BASE-T transceivers
All ports (2 to 13) use the internal
10BASE-T transceivers
Function
Information