nStatus held low Cyclone IV EP4CE6E22

[Altera_Forum]

Hi, 

 I've designed a board with a Cyclone IV EP4CE6E22.  I have a problem with the config on the JTAG chain. My device is not detected.  I've checked all Vcc (I/O=3.3V, PLLA = 2.5V, VccINT= 1.2V) ; nConfig is high but nStatus held low. I have 10k pull-up (Vcc 3.3V) on this pin.   I don't understand what is my problem.   Please, help me.  Thanks  Alain

[Altera_Forum]

Hi Alain, 

 This may be because of noise in DCLK and DATA line/bus signals or Msel setting or pull-up/pull-down resistors (nCE, nCONFIG, nSTATUS and CONF_DONE pins).  1. Did you test .sof file programming via JTAG configuration?  2. Are MSEL pins are tied to the correct MSEL setting?  For FPGA Configuration Troubleshooter refer the below link. https://www.altera.com/support/support-resources/support-centers/devices/cfg-index/fpga-configuration-troubleshooter.html  Let me know if this has helped resolve the issue you are facing or if you need any further assistance.  Best Regards, Anand Raj Shankar (This message was posted on behalf of Intel Corporation)

[Altera_Forum]

Hi, 

Thanks for your reply.  1. I can't test .sof because of my device is not detected. 2. MSEL are tied to GND, nCE to GND, nCONFIG, nSTATUS and conf_done pins with 10k pull-up.  For the moment, I just use JTAG configuration with ALTERA USB BLASTER. Because my device is not detected. If I can pass this first step, I will connect the EPCQ4.  I 've checked the steps of the link you send me. No result... I've replaced the CYCLONE too and try an other USB BLASTER.   The power-up screenshot of the 3 supply 1.2V, 2.5V , 3.3V.  https://www.alteraforum.com/forum/attachment.php?attachmentid=15605   Best regards Alain

[Altera_Forum]

The package you're using has a GND pad on the bottom of it. Is that electrically connected to your PCB? 

 From the datasheet:  --- Quote Start ---  The E144 package has an exposed pad at the bottom of the package. This exposed pad is a ground pad that must be connected to the ground plane of your PCB. Use this exposed pad for electrical connectivity and not for thermal purposes.  --- Quote End ---    There are quite a few posts on this forum relating to exactly this. Not connecting does cause problems - like yours.  Cheers, Alex

[Altera_Forum]

Hi Alex, 

 Thanks a lot for your reply.  You 're right, it was my problem. I've removed the FPGA, connected this pad to gnd and re-soldered it, QUARTUS detected the device.   I've learn a lot of posts, but never read this. I think, I don't have the good tag to find it...  Best regards   Alain