Configuration Handbook - Kamami.pl

Configuring Cyclone FPGAsWhen multiple Cyclone devices are cascaded, the compression featurecan be selectively enabled for each device in the chain. Figure 13–4depicts a chain of two Cyclone FPGAs. The first Cyclone FPGA has thecompression feature enabled and therefore receives a compressed bitstream from the configuration device. The second Cyclone FPGA has thecompression feature disabled and receives uncompressed data.Figure 13–4. Compressed & Uncompressed Configuration Data in the SameProgramming File Note (1)Serial DataCompressedUncompressedSerial or EnhancedConfigurationDeviceDecompressionControllerCyclone FPGADecompressionControllerCyclone FPGAnCEnCEOnCE nCEO N.C.GNDNote to Figure 13–4:(1) The first device in the chain should be set up in AS configuration mode(MSEL[1..0]="00"). The remaining devices in the chain must be set up in PSconfiguration mode (MSEL[1..0]="01").You can generate programming files for this setup from the ConvertProgramming Files window (File menu) in the Quartus II software.The decompression feature supported by Cyclone FPGAs is separatefrom the decompression feature in enhanced configuration devices(EPC16, EPC8, and EPC4 devices). The data compression feature in theenhanced configuration devices allows them to store compressed dataand decompress the bit stream before transmitting to the target devices.When using Cyclone FPGAs with enhanced configuration devices, Alterarecommends using compression on one of the devices, not both(preferably the Cyclone FPGA since transmitting compressed datareduces configuration time).Altera Corporation 13–7January 2007 Cyclone Device Handbook, Volume 1