ICS1893BY-10 - Release
Chapter 4 Operating Modes Overview
4.1 Reset Operations
This section first discusses reset operations in general and then specific ways in which the ICS1893BY-10
can be configured for various reset options.
4.1.1 General Reset Operations
The following reset operations apply to all the specific ways in which the ICS1893BY-10 can be reset,
which are discussed in Section 4.1.2, “Specific Reset Operations”.
4.1.1.1 Entering Reset
When the ICS1893BY-10 enters a reset condition (either through hardware, power-on reset, or software), it
does the following:
1. Isolates the MAC/Repeater Interface input pins
2. Drives all MAC/Repeater Interface output pins low
3. Tri-states the signals on its Twisted-Pair Transmit pins (TP_TXP and TP_TXN)
4. Initializes all its internal modules and state machines to their default states
5. Enters the power-down state
6. Initializes all internal latching low (LL), latching high (LH), and latching maximum (LMX) Management
Register bits to their default values
4.1.1.2 Exiting Reset
When the ICS1893BY-10 exits a reset condition, it does the following:
1. Exits the power-down state
2. Latches the Serial Management Port Address of the ICS1893BY-10 into the Extended Control
Register, bits 16.10:6. [See Section 7.11.3, “PHY Address (bits 16.10:6)”.]
3. Enables all its internal modules and state machines
4. Sets all Management Register bits to either (1) their default values or (2) the values specified by their
associated ICS1893BY-10 input pins, as determined by the HW/SW pin
5. Enables the Twisted-Pair Transmit pins (TP_TXP and TP_TXN)
6. Resynchronizes both its Transmit and Receive Phase-Locked Loops, which provide its transmit clock
(TXCLK) and receive clock (RXCLK)
7. Releases all MAC/Repeater Interface pins, which takes a maximum of 640 ns after the reset condition
is removed
4.1.1.3 Hot Insertion
As with the ICS189X products, the ICS1893BY-10 reset design supports ‘hot insertion’ of its MII. (That is,
the ICS1893BY-10 can connect its MAC/Repeater Interface to a MAC/repeater while power is already
applied to the MAC/repeater.)
ICS1893BY-10 Rev A 3/24/04
March, 2004
Copyright © 2004, Integrated Circuit Systems, Inc.
All rights reserved.
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ICSI [ INTEGRATED CIRCUIT SOLUTION INC ]
