ICS1892 Datasheet, PDF (112/148 Pages) Integrated Circuit Systems – 10Base-T/100Base-TX Integrated PHYceiver

ICS1892 Data Sheet
Chapter 9 Pin Diagram, Listings, and Descriptions
Table 9-6. MAC/Repeater Interface Pins: Media Independent Interface (MII) (Continued)
Pin
Pin
Pin
Name Number Type
Pin Description
TXEN
44
Input Transmit Enable.
The signal on this pin indicates to the ICS1892 that the MAC/repeater is
sending valid data nibbles for transmission on the physical media.
• Synchronous with the assertion of TXEN, the ICS1892 begins reading
the data nibbles on the transmit data lines and transmitting them over
the media.
• Following the de-assertion of TXEN, the ICS1892 terminates
transmission of nibbles.
TXER
42
Input Transmit Error.
When the mode is:
• 10Base-T, TXER is not required.
• 100Base-TX mode:
– The assertion of TXER by the MAC/repeater causes the ICS1892 to
transmit Invalid Symbols. (The ICS1892 synchronously samples the
TXER signal on the rising edges of TXCLK.)
– The Invalid Symbol used for this function is the HALT symbol, which
is substituted for the transmit nibble received from the
MAC/repeater.
– When the Invalid Error Code Test bit (bit 16.2) is set to logic one, the
5-bit symbol shown in the Invalid Error Code Translation Table
(Table 8-17) is used instead of the normal 4B/5B encoding described
in the ISO/IEC specification.
ICS1892, Rev. D, 2/26/01
© 2000-2001, Integrated Circuit Systems, Inc.
All rights reserved.
112
February 26, 2001