EP1AGX ALTERA [Altera Corporation], EP1AGX Datasheet - Page 76

• Manufacturer Part Number: EP1AGX
• Description: Section I. Arria GX Device Data Sheet
• Manufacturer: ALTERA [Altera Corporation]

2–70
Figure 2–58. Global Clock Control Blocks
Notes to
(1) These clock select signals can be dynamically controlled through internal logic when the device is operating in user mode.
(2) These clock select signals can only be set through a configuration file (SRAM Object File [.sof] or Programmer Object File [.pof]) and cannot be
Figure 2–59. Regional Clock Control Blocks
Notes to
(1) These clock select signals can only be set through a configuration file (.sof or .pof) and cannot be dynamically controlled during user mode
(2) Only the CLKn pins on the top and bottom of the device feed to regional clock select.
Arria GX Device Handbook, Volume 1
dynamically controlled during user mode operation.
operation.
Figure
Figure
2–58:
2–59:
Clock Control Block
Each GCLK, RCLK, and PLL external clock output has its own clock control block.
The control block has two functions:
■
■
Figure 2–58
regional clock, and PLL external clock output, respectively.
Clock source selection (dynamic selection for global clocks)
Clock power-down (dynamic clock enable or disable)
CLKSELECT[1..0]
(1)
This multiplexer supports
User-Controllable
Dynamic Switching
through
PLL Counter
PLL Counter
Outputs
Outputs
Figure 2–60
2
2
2
CLKp
CLKp
Pins
Pin
Enable/
Disable
RCLK
2
CLKn
Pin
show the clock control block for the global clock,
Enable/
Disable
GCLK
CLKn
Pin
(2)
Internal
Logic
Static Clock Select (1)
Internal
Logic
Internal
Logic
Internal
Static Clock Select
Logic
(2)
© December 2009 Altera Corporation
Chapter 2: Arria GX Architecture
PLLs and Clock Networks