Configuration Handbook - Kamami.pl

Device Configuration PinsDeviceConfigurationPinsThe following tables describe the connections and functionality of all theconfiguration related pins on the Mercury, APEX 20K (2.5 V), ACEX 1K,or FLEX 10K device. Table 8–20 describes the dedicated configurationpins, which are required to be connected properly on your board forsuccessful configuration. Some of these pins may not be required for yourconfiguration schemes.Table 8–20. Dedicated Configuration Pins (Part 1 of 4)Pin NameMSEL0MSEL1UserModeConfigurationSchemePin TypeDescriptionN/A All Input Two-bit configuration input that sets the Mercury,APEX 20K (2.5 V), ACEX 1K, or FLEX 10K deviceconfiguration scheme. See Table 8–6 for the appropriateconnections. These pins must remain at a valid stateduring power-up, before nCONFIG is pulled low to initiatea reconfiguration and during configuration.VCCSEL N/A All Input This pin is only available in Mercury devices. Dedicatedinput that ensures the configuration related I/O bankshave powered up to the appropriate 1.8-V or 2.5-V/3.3-Vvoltage levels before starting configuration. A logic high(1.5 V, 1.8 V, 2.5 V, 3.3 V) means 2.5 V/3.3 V, and a logiclow means 1.8 V.nCONFIG N/A All Input Configuration control input. Pulling this pin low duringuser-mode will cause the FPGA to lose its configurationdata, enter a reset state, tri-state all I/O pins, andreturning this pin to a logic high level will initiate areconfiguration.If your configuration scheme uses an enhancedconfiguration device or EPC2 device, nCONFIG can betied directly to V CC or to the configuration device’snINIT_CONF pin.8–64 Altera CorporationConfiguration Handbook, Volume 1 August 2005