Datasheet
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DP83848YB
AN_EN (LED_ACT/COL)
AN_1 (LED_SPEED)
AN_0 (LED_LINK)
S, O, PU 26
27
28
Auto-Negotiation Enable: When high, this enables Auto-Negoti-
ation with the capability set by ANO and AN1 pins. When low, this
puts the part into Forced Mode with the capability set by AN0 and
AN1 pins.
AN0 / AN1: These input pins control the forced or advertised op-
erating mode of the DP83848YB according to the following table.
The value on these pins is set by connecting the input pins to
GND (0) or V
CC
(1) through 2.2 kΩ resistors. These pins should
NEVER be connected directly to GND or VCC.
The value set at this input is latched into the DP83848YB at Hard-
ware-Reset.
The float/pull-down status of these pins are latched into the Basic
Mode Control Register and the Auto_Negotiation Advertisement
Register during Hardware-Reset.
The default is 111 since these pins have internal pull-ups.
MII_MODE (RX_DV)
SNI_MODE (TXD_3)
S, O, PD 39
6
MII MODE SELECT: This strapping option pair determines the
operating mode of the MAC Data Interface. Default operation (No
pull-ups) will enable normal MII Mode of operation. Strapping
MII_MODE high will cause the device to be in RMII or SNI mode
of operation, determined by the status of the SNI_MODE strap.
Since the pins include internal pull-downs, the default values are
0.
The following table details the configurations:
LED_CFG (CRS) S, O, PU 40 LED CONFIGURATION: This strapping option determines the
mode of operation of the LED pins. Default is Mode 1. Mode 1 and
Mode 2 can be controlled via the strap option. All modes are con
-
figurable via register access.
SeeTable 3 for LED Mode Selection.
MDIX_EN (RX_ER) S, O, PU 41 MDIX ENABLE: Default is to enable MDIX. This strapping option
disables Auto-MDIX. An external pull-down will disable Auto-
MDIX mode.
Signal Name Type Pin # Description
AN_EN AN1 AN0 Forced Mode
0 0 0 10BASE-T, Half-Duplex
0 0 1 10BASE-T, Full-Duplex
0 1 0 100BASE-TX, Half-Duplex
0 1 1 100BASE-TX, Full-Duplex
AN_EN AN1 AN0 Advertised Mode
1 0 0 10BASE-T, Half/Full-Duplex
1 0 1 100BASE-TX, Half/Full-Duplex
1 1 0 10BASE-T Half-Duplex
100BASE-TX, Half-Duplex
1 1 1 10BASE-T, Half/Full-Duplex
100BASE-TX, Half/Full-Duplex
MII_MODE SNI_MODE
MAC Interface
Mode
0 X MII Mode
1 0 RMII Mode
1 1 10 Mb SNI Mode