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Damaged KFLOP

Posted: Mon Jul 19, 2021 7:01 pm
by RogerFroud
I couldn't find a section to post this, so I've put it here.

I'm not entirely sure how this had happened, but there was an issue with the 24V power supply for the emergency stop circuit, and I suspect the board saw an over voltage.

Anyway, the Xilinx XC3S100E-4TQG144C is now getting hot, and the 5V power supply is being pulled down.

So the question is, can I replace the chip and reprogram that somehow, assuming this is the only fault? It's not economical to return it from the UK for repair, but I can get the chip replaced locally so see if that fixes the issue.

Re: Damaged KFLOP

Posted: Mon Jul 19, 2021 7:21 pm
by TomKerekes
Hi Roger,

Sorry to hear that. You could try it. The Xilinx chip is automatically configured by the DSP so there would be nothing for you to configure.

We don't find it cost effective to repair boards.

Re: Damaged KFLOP

Posted: Sat Jul 24, 2021 11:34 am
by RogerFroud
I've replaced the 3V3 regulator and the FPGA, and it now powers up with the two LEDs blinking before they end up permanently on. Does that sound right?

Initially I had the current limit on the power supply too low, and it kept tripping out without getting going.

So this looks more promising now. I think the USB chip may be damaged, since that's connected to the +5V supply that had the issue.

Re: Damaged KFLOP

Posted: Sat Jul 24, 2021 6:48 pm
by TomKerekes
Hi Roger,

That's promising. If you replace the FTDI chip it will need to be re-programmed.

There is an FTDI utility called FT_PROG.exe which should be here:
https://www.ftdichip.com/Support/Utilities.htm#FT_PROG

Use it to program the device with the template:
<Install>\USB Driver\KFLOP.xml

Good luck

Re: Damaged KFLOP

Posted: Mon Aug 16, 2021 1:03 pm
by RogerFroud
I've finally got the right FTDI chip fitted and programmed, it now shows up in the Device Manager as shown in the attached picture.

I've right clicked on that and pointed it to the USB driver, and it tells me that the best driver is already installed. That USB port works fine with the new board I've received, so that's not surprising. However, it says 'Can't Connect to KMotion Board 0x31 when I try to communitate with it.

I've selected Board 0 @ 0x31 using KMotion->USB Locations.

So to summarise, I get the exact same boot sequence on the good and bad boards showing with the flashing LEDs on bootup, finishing with both LEDs on. I can see it in the Device Manager, but something else is preventing it connecting.

Is there anything else in the setup that I'm missing? It seems like it's doing all of the right things, I'm surprised this doesn't work now?

Re: Damaged KFLOP

Posted: Mon Aug 16, 2021 2:23 pm
by TomKerekes
Hi Rodger,

Is the USB location 0x31?

You might try Flash Recovery.

Otherwise possibly a bad solder connection between the FPGA and USB chips?

Re: Damaged KFLOP

Posted: Mon Aug 16, 2021 7:18 pm
by RogerFroud
Many thanks for that, I've found a bad joint on one of the data lines to the FTDI chip, so it now communicates correctly with KMOTION.

All that remains is to hook it all back up to the KANALOG board and see if it now functions as a complete system.

Before doing that, I'll bus out each pin on the FPGA to make certain that every pin does connect to the pad it's supposed to be soldered to.

Re: Damaged KFLOP

Posted: Wed Aug 18, 2021 9:50 am
by RogerFroud
I've finally found the reason for the damage to the KLOP, there was a tiny streak of solder on one of the connectors to the differential drivers. Unfortunately, this happened to be a +24v connection to one of the Opto Isolators used for the output that controls the DC Brake.

I can't try it fully connected until the replacement IC arrives, but it does connect with the KANALOG board, and I get the LED on that board when it's completed booting. It certainly looks like this is going to work now.