Chapter 12: 10/100 IEEE802.3 Media Access Controller
TX7901 User’s Manual (Rev. 6.30T – Nov, 2001)
12-3
12.1.2 MAC
and
MII
The MAC consists of a transmit block, a receive block, a flow control block, a set of control
and status registers, counters and a serial controller for the MII (Media Independent
Interface) station management interface.
The transmit block buffers the outgoing data in the TxFIFO, encapsulates it, then passes it
on to the MII. The transmit block has logic for generating preamble and jam bytes, pad bytes,
and the CRC value. It also has logic and a timer for back-off delay after a collision, and a
timer for the inter-packet gap after a transmission.
The receive block de-encapsulates the received packet from the MII and stores it in the
RxFIFO. The receive block has circuits for checking the CRC value and packet lengths. It
also has an address table for accepting or rejecting of a packet based on its destination
address.
The TxFIFO and RxFIFO are both 1 KB in size.
Controls for the following network operations are included in the MAC:
•
Controls to enable and disable transmit and receive circuits
•
Controls to enable and disable interrupts for individual conditions
•
Address recognition controls, for up to 16 individual addresses
•
Counters and status bits for collecting network management data
•
Synchronizing the transmit signals to the transmit clock
•
Synchronizing the receive signals to the bus clock
•
Controls to enable and disable the PAUSE operation
•
Controls for reading and writing data in the TxFIFO and RxFIFO in the diagnostic
mode
•
Loop-back and other controls to aid in diagnosing problems
Summary of Contents for TMPR7901
Page 1: ...TX System RISC TX79 Family TMPR7901 Symmetric 2 way superscalar 64 bit CPU ...
Page 14: ...Handling Precautions ...
Page 15: ......
Page 17: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 41: ...4 Precautions and Usage Considerations 4 2 ...
Page 42: ...TX7901 User s Manual Rev 6 30T November 2001 DOCUMENT NUMBER M 99 00004 07 ...
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