ADM7001XACT1XP Lantiq, ADM7001XACT1XP Datasheet - Page 32

• Manufacturer Part Number: ADM7001XACT1XP
• Manufacturer: Lantiq

Specifications of ADM7001XACT1XP

• Lead Free Status / RoHS Status: Supplier Unconfirmed

3.1.13
The jabber function monitors the ADM7001 output and disables the transmitter if it attempts to transmit a longer
than legal sized packet. If TXEN is high for greater than 24ms, the 10Base-T transmitter will be disabled. Once
disabled by the jabber function, the transmitter stays disable for the entire time that the TXEN signal is asserted.
This signal has to be de-asserted for approximately 408 ms (The un-jab time) before the jabber function re-enables
the transmit outputs. The jabber function can be disabled by programming bit 0 of register address 10
3.1.14
A link pulse is used to check the integrity of the connection with the remote end. If valid link pulses are not received,
the link detector disables the 10Base-T twisted-pair transmitter, receiver, and collision detection functions.
The link pulse generator produces pulses as defined in IEEE 802.3 10Base-T standard. Each link pulse is
nominally 100 ns in duration and is transmitted every 16 ms, in the absence of transmit data. Setting bit 10 of
register 10
3.1.15
ADM7001's 10Base-T transceiver module incorporates an “automatic link polarity detection circuit”. The inverted
polarity is determined when seven consecutive link pulses of inverted polarity or three consecutive packets are
received with inverted end-of-packet pulses. If the input polarity is reversed, the error condition will be
automatically corrected and reported in bit 13 of register 11
3.1.16
The ADM7001 implements a clock synthesizer that generates all the reference clocks needed from a single
external frequency source. The clock source must be a TTL level signal at 25 MHz ± 50ppm.
3.1.17
The Auto Negotiation function provides a mechanism for exchanging configuration information between two ends
of a link segment and automatically selecting the highest performance mode of operation supported by both
devices. Fast Link Pulse (FLP) Bursts provides the signaling used to communicate auto negotiation abilities
between two devices at each end of a link segment. For further detail regarding auto negotiation, refer to Clause
28 of the IEEE 802.3u specification. The ADM7001 supports four different Ethernet protocols, so the inclusion of
auto negotiation ensures that the highest performance protocol will be selected based on the ability of the link
partner.
The auto negotiation function within the ADM7001 can be controlled either by internal register access or by the
use of configuration pins are sampled. If disabled, auto negotiation will not occur until software enables bit 12 in
register 0. If auto negotiation is enabled, the negotiation process will commence immediately.
When auto negotiation is enabled, the ADM7001 transmits the abilities programmed into the auto negotiation
advertisement register at address 04
duplex modes may be selected. Auto negotiation controls the exchange of configuration information. Upon
successfully auto negotiation, the abilities reported by the link partner are stored in the auto negotiation link partner
ability register at address 05
The contents of the “auto negotiation link partner ability register” are used to automatically configure to the highest
performance protocol between the local and far-end nodes. Software can determine which mode has been
configured by auto negotiation by comparing the contents of register 04
technology whose bit is set in both registers of highest priority relative to the following list.
•
•
•
Data Sheet
100Base-TX full duplex (highest priority)
100Base-TX half duplex
10Base-T full duplex
H
to high can disable link pulse check function.
Jabber Function
Link Test Function
Automatic Link Polarity Detection
Clock Synthesizer
Auto Negotiation
H
.
H
via FLP bursts. Any combination of 10 Mbps, 100 Mbps, half duplex and full
32
H
.
H
and 05
H
and then selecting the
Function Description
Rev. 1.07, 2005-09-12
Data sheet
ADM7001
H
to high.