78Q2123/78Q2133 MicroPHY™
10/100BASE-TX Transceiver
LED SIGNALS (PROGRAMMABILITY IS SECONDARY REQUIREMENT)
SIGNAL
PIN
TYPE DESCRIPTION
LED0
4
CO
PROGRAMMABLE LED. Active low. Default status: LINK OK. Active to indicate
link with far end PHY.
LED1
3
CO
PROGRAMMABLE LED. Active low. Default status: RX or TX ACTIVITY. Active
to indicate TX or RX activity on the MDI.
Other LED options selectable via MR23:
TRANSMIT: ON when there is a transmission (normally OFF).
RECEIVE: ON when there is a reception (normally OFF).
COLLISION: In half duplex mode, this is a collision indicator and turns-ON when a collision
occurs. In full duplex mode, this LED is held OFF.
BASE-TX: ON for 100BASE-TX connection and OFF for other connections.
LEDBTX is OFF during auto-negotiation.
BASE-T: ON for 10BASE-T connection and OFF for other connections. LEDBT is
OFF during auto-negotiation.
FULL DUPLEX: ON when in full duplex mode and OFF when in half duplex mode.
LINK/ACT: ON for link, blink for activity.
Page: 10 of 42
© 2009 Teridian Semiconductor Corporation
Rev 1.5
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
