Altera Phase-Locked Loop Reconfiguration IP Core - Manual (Page 7)

Functional Description—Implementing Multiple Reconfiguration Using an External ROM Page 7
Phase-Locked Loop Reconfiguration (ALTPLL_RECONFIG) Megafunction February 2012 Altera Corporation
The input and output ports to support reconfiguration using multiple configuration
files are shown in
Figure 3 , circled in red.
The reconfiguration feature using multiple configuration files allows you to feed data
from multiple ROMs to a multiplexer that feeds the
rom _ data _ in port. Figure 4 shows
a sample design. In this scheme, the write _ rom _ ena signal feeds back to the ROM as
the enable signal, which allows the ROM to be read out. The rom _ address _ out bus
provides the intended ROM address, which determines the exact ROM data.
Figure 3. Ports to Support Reconfiguration Using Multiple Configuration Files
Figure 4. Typical Scheme for Reconfiguring PLLs from External ROMs
data_in[8:0]
inst
ALTPLL_RECONFIG
counter_type[3:0]
reconfig
busy
data_out[8:0]
pll_scanclk
pll_scandata
read_param
write_param
counter_param[2:0]
pll_scandataout
clock
reset
pll_areset_in
write_from_rom
rom_data_in
reset_rom_address
pll_scanaclr
pll_areset
rom_address_out
write_rom_ena
M
U
X
ROM
ROM
ROM
altpll_reconfig
write_from_rom
rom_data_in
write_rom_ena
rom_address_out