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Altera_Forum
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10 years ago

nstatus get low periodic

it is a new board,VCCINT is 1.14V,VCC is 3.32V .VCCA is 2.48V,VCCD_pll is 1.15V.JTAG can not find the device. when I check the state of FPGA,I find that pin of con_done is low, and pin of nSTATUS...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
10 years ago

It seems like your config is failing and Auto-restart is configured. From the Cyclone IV Handbook:

"Configuration Error

If an error occurs during configuration, Cyclone IV devices assert the nSTATUS signal low, indicating a data frame error and the CONF_DONE signal stays low. If the Auto-restart configuration after error option (available in the Quartus II software in the General tab of the Device and Pin Options dialog box) is turned on, the Cyclone IV device releases nSTATUS after a reset time-out period (a maximum of 230 s), and retries configuration. If this option is turned off, the system must monitor nSTATUS for errors and then pulse nCONFIG low for at least 500 ns to restart configuration."

John D