Datasheet

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DP83849ID
MII_MODE_A (RX_DV_A)
SNI_MODE_A (TXD3_A)
MII_MODE_B (RX_DV_B)
SNI_MODE_B (TXD3_B)
S, O, PD 80
17
62
45
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 modes
of operation, determined by the status of the SNI_MODE strap.
Since the pins include internal pull-downs, the default values are
0. Both MAC Data Interfaces must have their RMII Mode settings
the same, i.e. both in RMII mode or both not in RMII mode.
The following table details the configurations:
LED_CFG_A
(CRS_A/CRS_DV_A)
LED_CFG_B
(CRS_B/CRS_DV_B)
S, O, PU 1
61
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.
See Tabl e 3 on page 20 for LED Mode Selection.
MDIX_EN_A (RX_ER_A)
MDIX_EN_B (RX_ER_B)
S, O, PU 2
60
MDIX ENABLE: Default is to enable MDIX. This strapping option
disables Auto-MDIX. An external pull-down will disable Auto-MDIX
mode.
ED_EN_A (RXD3_A)
ED_EN_B (RXD3_B)
S, O, PD 9
53
Energy Detect ENABLE: Default is to disable Energy Detect
mode. This strapping option enables Energy Detect mode for the
port. In Energy Detect mode, the device will initially be in a low-
power state until detecting activity on the wire. An external pull-up
will enable Energy Detect mode.
CLK2MAC_DIS (RXD2_A) S, O, PD 8 Clock to MAC Disable: This strapping option disables (floats) the
CLK2MAC pin. Default is to enable CLK2MAC output. An external
pullup will disable (float) the CLK2MAC pin. If the system does not
require the CLK2MAC signal, the CLK2MAC output should be dis
-
abled via this strap option.
Signal Name Type Pin # Description
MII_MODE SNI_MODE MAC Interface
Mode
0 X MII Mode
1 0 RMII Mode
1 1 10 Mb SNI Mode