Configuration Handbook - Kamami.pl

Configuring Cyclone II DevicesWhen designing a Cyclone II board for JTAG configuration, use theguidelines in Table 13–10 for the placement of the dedicatedconfiguration pins.Table 13–10. Dedicated Configuration Pin Connections During JTAGConfigurationSignalnCEnCEOMSELnCONFIGnSTATUSCONF_DONEDCLKDescriptionOn all Cyclone II devices in the chain, nCE should be drivenlow by connecting it to ground, pulling it low via a resistor, ordriving it by some control circuitry. For devices that are also inmultiple device AS, or PS configuration chains, the nCE pinsshould be connected to GND during JTAG configuration orJTAG configured in the same order as the configuration chain.On all Cyclone II devices in the chain, nCEO can be used as auser I/O or connected to the nCE of the next device. If nCEO isconnected to the nCE of the next device, the nCEO pin mustbe pulled high to V CCIO by an external 10-kΩ pull-up resistorto help the internal weak pull-up resistor. If the nCEO pin is notconnected to the nCE pin of the next device, you can use it asa user I/O pin after configuration.These pins must not be left floating. These pins supportwhichever non-JTAG configuration is used in production. Ifonly JTAG configuration is used, you should tie these pins toground.Driven high by connecting to V CC , pulling up via a resistor, ordriven high by some control circuitry.Pull to V CC via a 10-kΩ resistor. When configuring multipledevices in the same JTAG chain, each nSTATUS pin shouldbe pulled up to V CC individually. nSTATUS pulling low in themiddle of JTAG configuration indicates that an error hasoccurred.Pull to V CC via a 10-kΩ resistor. When configuring multipledevices in the same JTAG chain, each CONF_DONE pinshould be pulled up to V CC individually. CONF_DONE goinghigh at the end of JTAG configuration indicates successfulconfiguration.Should not be left floating. Drive low or high, whichever is moreconvenient on your board.Figure 13–23 shows JTAG configuration of a Cyclone II device with amicroprocessor.Altera Corporation 13–57February 2007 Cyclone II Device Handbook, Volume 1