HC4GX15 Datasheet, PDF (568/668 Pages) Altera Corporation – HardCopy IV Device Handbook

2–110
Chapter 2: HardCopy IV GX Dynamic Reconfiguration
Description of Transceiver Channel Reconfiguration Modes
How to Use the logical_tx_pll_sel Port?
■ Enable both the logical_tx_pll_sel and logical_tx_pll_sel_en ports.
■ Specify the logical reference index of the CMU PLL used in the reconfiguration at
logical_tx_pll_sel.
■ Set a value of 0 or 1 at this port. These 0 and 1 values correspond to the logical
reference index that you have already set in the ALTGX MegaWizard Plug-In
Manager in the following options:
■ What is the main transmitter PLL logical reference index?
■ What is the alternate transmitter PLL logical reference index?
■ Set logical_tx_pll_sel_en to 1'b1 (the dynamic reconfiguration controller
uses the logical reference index value set at logical_tx_pll_sel instead of
logical tx pll stored in the .mif).
When Can the logical_tx_pll_sel and logical_tx_pll_sel_en Ports be Used?
By default, the ALTGX_RECONFIG MegaWizard Plug-In Manager enables the
logical_tx_pll_sel and logical_tx_pll_sel_en ports when you select the
Channel and TX PLL select/reconfig option as the reconfiguration mode.
■ Condition 1: If you want to use the logical_tx_pll_sel only under some
conditions and use the logical tx pll (logical reference index value stored in the
.mif) otherwise:
■ Both the logical_tx_pll_sel and the logical_tx_pll_sel_en ports
are enabled by default.
■ Therefore, if you want to use the logical tx pll value stored in the .mif, set
logical_tx_pll_sel_en to 1'b0.
■ Instead, if you want to use the value at logical_tx_pll_sel, set
logical_tx_pll_sel_en to 1'b1. (The dynamic reconfiguration controller
uses the value set at logical_tx_pll_sel only when you set
logical_tx_pll_sel_en to 1'b1, as shown in Figure 2–52).
Figure 2–52. Using logical_tx_pll_sel and logical_tx_pll_sell_en Ports
logical tx pll
(logical reference
index value stored
in the .mif)
ALTGX_RECONFIG
instance
0
selected
logical reference index
value
logical_tx_pll_sel[1:0]
1
(logical reference index
specified in the ALTGX_RECONFIG
MegaWizard Plug-In Manager)
HardCopy IV Device Handbook, Volume 3
logical_tx_pll_sel_en
© June 2009 Altera Corporation