Configuration Handbook - Kamami.pl

Device Configuration Overview■The Remote System Configuration with Stratix & Stratix GX DeviceschapterfFor more information on setting device configuration options orgenerating configuration files, see the Software Setting chapter inVolume 2 of the Configuration Handbook.DeviceConfigurationOverviewDuring device operation, the FPGA stores configuration data in SRAMcells. Because SRAM memory is volatile, you must load the SRAM cellswith the configuration data each time the device powers up. Afterconfiguration, the device must initialize its registers and I/O pins. Afterinitialization, the device enters user mode. Figure 11–1 shows the state ofthe device during the configuration, initialization, and user mode.Figure 11–1. Stratix & Stratix GX Configuration CyclenCONFIGnSTATUSCONF_DONE (1)DCLKDATAUser I/O Pins (2)INIT_DONE (3)MODEHigh-ZD(N – 1)(4)D0 D1 D2 D3DN High-Z(5)High-ZUser I/OConfiguration Configuration Initialization UserNotes to Figure 11–1:(1) During initial power up and configuration, CONF_DONE is low. After configuration, CONF_DONE goes high. If thedevice is reconfigured, CONF_DONE goes low after nCONFIG is driven low.(2) User I/O pins are tri-stated during configuration. Stratix and Stratix GX devices also have a weak pull-up resistoron I/O pins during configuration that are enabled by nIO_PULLUP. After initialization, the user I/O pins performthe function assigned in the user’s design.(3) If the INIT_DONE pin is used, it will be high because of an external 10 kΩ resistor pull-up when nCONFIG is lowand during the beginning of configuration. Once the option bit to enable INIT_DONE is programmed into the device(during the first frame of configuration data), the INIT_DONE pin will go low.(4) DCLK should not be left floating. It should be driven high or low.(5) DATA0 should not be left floating. It should be driven high or low.You can load the configuration data for the Stratix or Stratix GX deviceusing a passive configuration scheme. When using any passiveconfiguration scheme, the Stratix or Stratix GX device is incorporated intoa system with an intelligent host, such as a microprocessor, that controlsthe configuration process. The host supplies configuration data from astorage device (e.g., a hard disk, RAM, or other system memory). Whenusing passive configuration, you can change the target device’s11–2 Altera CorporationStratix Device Handbook, Volume 2 July 2005