
R
Chapter 11: Dynamic Switching of
Operation of the Core
Selecting the Power-On / Reset Standard
The external port of the core, basex_or_sgmii (see “Dynamic Switching Signal Pinout” in Chapter 2), will select the default standard of the core as follows:
•Tie to logic ‘0’ in the core instantiation. The core
•Tie to logic ‘1’ in the core instantiation. The core
The basex_or_sgmii port of the core could be dynamically driven. In this configura- tion, it is possible to drive a logical value onto the port, followed by a core reset cycle to switch the core to the desired standard. However, it is expected that the standard will be switched through the MDIO Management Registers.
Switching the Standard Using MDIO
The
•Core set to
•Core set to SGMII standard. Management Registers 0 through 16 should be interpreted according to “SGMII Standard Using the Optional
Auto-Negotiation State Machine
•Core set to the
•Core set to perform the SGMII standard. The
•Standard is switched during an
•Switching the standard using MDIO. This does not cause
♦If you have switched to the
♦For either standard, restart the
Setting the Auto-Negotiation Link Timer
As described in
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| UG155 March 24, 2008 |