Configuration Handbook - Kamami.pl

Configuration SchemesConfigurationSchemesThis section describes the various configuration schemes you can use toconfigure Cyclone FPGAs. Descriptions include an overview of theprotocol, pin connections, and timing information. The schemesdiscussed are:■■■AS configuration (serial configuration devices)PS configurationJTAG-based configurationActive Serial Configuration (Serial Configuration Devices)In the AS configuration scheme, Cyclone FPGAs are configured using thenew serial configuration devices. These configuration devices are lowcost devices with non-volatile memory that feature a simple four-pininterface and a small form factor. These features make serialconfiguration devices an ideal solution for configuring the low-costCyclone FPGAs.fFor more information on programming serial configuration devices, seethe Cyclone Literature web page and the Serial Configuration Devices(EPCS1, EPCS4, EPCS16 & EPCS64) Data Sheet.Serial configuration devices provide a serial interface to accessconfiguration data. During device configuration, Cyclone FPGAs readconfiguration data via the serial interface, decompress data if necessary,and configure their SRAM cells. This scheme is referred to as an ASconfiguration scheme because the FPGA controls the configurationinterface. This scheme is in contrast to the PS configuration scheme wherethe configuration device controls the interface.Serial configuration devices have a four-pin interface: serial clock input(DCLK), serial data output (DATA), AS data input (ASDI), and an activelowchip select (nCS). This four-pin interface connects to Cyclone FPGApins as shown in Figure 13–5.13–8 Altera CorporationCyclone Device Handbook, Volume 1 January 2007