Xilinx LogiCORE IP MAC v8.5, Руководство пользователя

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1-Gigabit Ethernet MAC v8.5 User Guide www.xilinx.com 77
UG144 April 24, 2009
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Chapter 8
Configuration and Status
This chapter provides general guidelines for configuring and monitoring the GEMAC
core, including a detailed description of the client-side management interface and registers
present in the core. It also describes the alternative to the optional management interface
which is the Configuration Vector.
Using the Optional Management Interface
The Management Interface is a processor-independent interface with standard address,
data, and control signals. It may be used as is, or a wrapper (not supplied) may be used to
interface to common bus architectures. For port definition, see
“Management Interface
(Optional),” on page 28 .
This interface is used for:
•
Configuring of the GEMAC core via the configuration registers.
•
Access through the MDIO interface to the management registers located in the PHY
connected to the GEMAC core.
The Management Interface can be accessed in different ways, depending on the type of
transaction. A truth table showing which access method is required for each transaction
type is shown in
Table 8-1 . These access methods are described in the following sections.
Host Clock Frequency
The Management Interface clock,
host_clk
, is used to derive the MDIO clock,
mdc
, and
for this reason is subject to the following frequency restriction:
≥
10 MHz
Configuring the GEMAC core to derive the
mdc
signal from this clock is detailed in “MDIO
Interface,” on page 86 .
Table 8-1: Management Interface Transaction Types
Transaction host_miim_sel host_addr[9]
Configuration 0 1
MIIM access 1 X