7–8
Altera Corporation
Stratix II Device Handbook, Volume 2
January 2008
Configuration Features
6.
Select the name of the file you added to the SOF Data area and click
Properties
.
7.
Check the Compression check box.
When multiple Stratix II or Stratix II GX devices are cascaded, you can
selectively enable the compression feature for each device in the chain if
you are using a serial configuration scheme.
Figure 7–2 depicts a chain of
two Stratix II or Stratix II GX devices. The first Stratix II or Stratix II GX
device has compression enabled and therefore receives a compressed bit
stream from the configuration device. The second Stratix II or
Stratix II GX device has the compression feature disabled and receives
uncompressed data.
In a multi-device FPP configuration chain all Stratix II or Stratix II GX
devices in the chain must either enable of disable the decompression
feature. You can not selectively enable the compression feature for each
device in the chain because of the DATA and DCLK relationship.
Figure 7–2. Compressed and Uncompressed Configuration Data in the Same
Configuration File
You can generate programming files for this setup from the Convert
Programming Files
window (File menu) in the Quartus II software.
Design Security Using Configuration Bitstream Encryption
Stratix II and Stratix II GX devices are the industry’s first devices with the
ability to decrypt a configuration bitstream using the Advanced
Encryption Standard (AES) algorithm—the most advanced encryption
algorithm available today. When using the design security feature, a
nCE
GND
nCEO
Decompression
Controller
Stratix II or
Stratix II GX
FPGA
nCE
nCEO
N.C.
Serial Configuration Data
Compressed
Uncompressed
Configuration
Data
Configuration
Data
Serial or Enhanced
Configuration
Device
Stratix II or
Stratix II GX
FPGA
