Configuration Handbook - Kamami.pl

Passive Parallel Asynchronous ConfigurationYou can use a single configuration chain to configure APEX 20KE andAPEX 20KC devices with other Altera devices that support PPAconfiguration, such as Stratix ® , Mercury, APEX II, ACEX 1K, andFLEX 10KE devices. To ensure that all devices in the chain completeconfiguration at the same time or that an error flagged by one deviceinitiates reconfiguration in all devices, all of the device CONF_DONE andnSTATUS pins must be tied together.fFor more information on configuring multiple Altera devices in the sameconfiguration chain, refer to Configuring Mixed Altera FPGA Chains in theConfiguration Handbook.Figure 7–23 shows the timing waveform for the PPA configurationscheme using a microprocessor.Figure 7–23. APEX 20KE & APEX 20KC PPA Configuration Timing Waveformt CFGt STATUSnCONFIGnSTATUS (1)CONF_DONE (2)DATA[7..0]t CF2ST1t DSUt CSSUt CSHt CD2UMByte 0 Byte 1Byte n 1Byte n(4)(3) CS(3) nCSnWSRDYnBSY(4)t t CF2WSDH(4)t WSP(4)t RDY2WS(4)t WS2Bt BUSYt CF2ST0t CF2CDUser I/OsHigh-ZHigh-ZUser-ModeINIT_DONENotes to Figure 7–23:(1) Upon power-up, the APEX 20KE or APEX 20KC device holds nSTATUS low for not more than 5 μs after V CCINTreaches its minimum requirement.(2) Upon power-up, before and during configuration, CONF_DONE is low.(3) The user can toggle nCS or CS during configuration if the design meets the specification for t CSSU , t WSP , and t CSH .(4) DATA0 should not be left floating after configuration. It should be driven high or low, whichever is more convenient.DATA[7..1], CS, nCS, nWS, nRS and RDYnBSY are available as user I/O pins after configuration and the state oftheses pins depends on the dual-purpose pin settings.Figure 7–24 shows the timing waveform for the PPA configurationscheme when using a strobed nRS and nWS signal.7–50 Altera CorporationConfiguration Handbook, Volume 1 August 2005