HC4GX15 Datasheet, PDF (562/668 Pages) Altera Corporation – HardCopy IV Device Handbook

2–104
Chapter 2: HardCopy IV GX Dynamic Reconfiguration
Description of Transceiver Channel Reconfiguration Modes
Consider that the transceiver channel is listening to CMU0 PLL and that you want to
reconfigure CMU0 PLL, as shown in Figure 2–49.
Figure 2–49. Reconfiguring the CMU0 PLL
Main PLL
logical_tx_pll value = 1 (provided by
the user in the ALTGX MegaWizard
Plug-In Manager)
refclk0 156.25 MHz
refclk1
125 MHz
CMU Channels
clock
mux
6.25 Gbps
CMU0 PLL
2.5 Gbps
clock
CMU1 PLL
mux
Full Duplex Transceiver Channel
1
TX CHANNEL
Logical
TX PLL
select
0
LOCAL
DIVIDER
6.25 Gbps
digital+analog logic
RX CHANNEL
clock
6.25 Gbps
6.25 Gbps
mux
RX PLL
digital+analog logic
Active Connections
Unused Connections
Alternate PLL
logical_tx_pll value = 0
(automatically set by the ALTGX
MegaWizard Plug-In Manager)
You can select CMU0 PLL by specifying its identity in the ALTGX MegaWizard
Plug-In Manager. This identification is referred to as the logical tx pll value.
This value provides a logical identification to CMU0 PLL and associates it with a
transceiver channel without requiring the knowledge of its physical location.
In the ALTGX MegaWizard Plug-In Manager, the transmitter PLL configuration set in
the General screen is called the main PLL. When you provide the main PLL with a
logical tx pll value, for example 1, the alternate PLL automatically takes the
complement value 0. The logical tx pll value for the main PLL is stored along with the
other transceiver channel information in the generated .mif.
1 You can reuse the .mif generated for one CMU PLL to reconfigure the other CMU PLL
in the same or other transceiver blocks.
Provide the logical tx pll value for the main PLL in the What is the main PLL logical
reference index? option in the Reconfig Clks screen.
HardCopy IV Device Handbook, Volume 3
© June 2009 Altera Corporation