LAN9303 Datasheet, PDF (36/366 Pages) SMSC Corporation – Small Form Factor Three Port 10/100 Managed Ethernet Switch with Single MII/RMII/Turbo MII

NUM
PINS
NAME
LED 1
GPIO 1
1
Port 2 Auto-
MDIX Enable
and
LED 1 Polarity
Configuration
Strap
Small Form Factor Three Port 10/100 Managed Ethernet Switch with Single MII/RMII/Turbo MII
Datasheet
Table 3.5 GPIO/LED/Configuration Straps (continued)
SYMBOL
BUFFER
TYPE
DESCRIPTION
LED1
GPIO1
AMDIX2_LED1P
O12/
OD12/
OS12
IS/O12/
OD12
(PU)
IS
(PU)
This pin is configured to operate as an LED when
the LED 1 Enable bit in the LED Configuration
Register (LED_CFG) is set. The buffer type
depends on the setting of the LED Function 1-0
(LED_FUN[1:0]) field in the LED Configuration
Register (LED_CFG) and is configured to be either
an push-pull or open-drain/open-source output.
When selected as an open-drain/open-source
output, the polarity of this pin depends up the
AMDIX2_LED1P strap value sampled at reset.
This pin is configured to operate as a GPIO when
the LED 1 Enable bit of the LED Configuration
Register (LED_CFG) is clear. The pin is fully
programmable as either a push-pull output, an
open-drain output, or a Schmitt-triggered input by
writing the General Purpose I/O Configuration
Register (GPIO_CFG) and the General Purpose
I/O Data & Direction Register (GPIO_DATA_DIR).
This strap configures the default for the Auto-MDIX
soft-strap for LAN Port 2, as well as the polarity of
the LED 1 pin when it is an open-drain or open-
source output. See Note 3.6.
The strap value determines whether or not LAN
Port 2 Auto-MDIX is enables as follows:
0 = Disabled
1 = Enabled
For LED 1, If the strap value is 0:
The LED is set as active high, since it is assumed
that a LED to ground is used as the pull-down.
If the strap value is 1:
The LED is set as active low, since it is assumed
that a LED to VDD is used as the pull-up.
Revision 1.3 (08-27-09)
36
DATASHEET
SMSC LAN9303/LAN9303i