Bitfile repeat download problem

I have built a simple MicroBlaze project in ISE/EDK 9.2.02i targetting the XEM3010.

I used the import peripheral wizard to make a simple no-busses, no-interrupts peripheral that: (i) sets i2c_sda and i2c_scl to ‘Z’ and hi_muxsel to ‘0’ and (ii) connects buttons and leds to a gpio. The project doesn’t touch the other hi_xxx pins.

I used a Platform Cable USB / JTAG to download it and it and ran OK.

Attempts to download using FrontPanel failed until I edited the etc/bitgen.ut to set the StartUpClock to CCLK. A lesson was learnt, there.

The problem is that once my code is loaded and the MicroBlaze is running, FrontPanel reports a USB connection failure when I attempt to download over the top of my bitstream. Also, if Frontpanel is re-started when my code is loaded, it crashes; generating a windows ‘Send Error Report’ dialog.

What could it be in my bitstream that is causing the USB link to fail?



First, could you please send that bitfile to support @ opalkelly . com ? Although we probably can’t determine much on the FPGA side with just the bitfile, we should be able to fix the FrontPanel crash.

Second, with your bitgen settings, what happens if you set the unused pin behavior to “PullNone” ?