J-Link Disconnects Randomly When Uploading & Debugging

(Jesse) #1

I have a HiFive1 Rev B
I am using Freedom Studio on Windows 10 with the hello and welcome examples.

I am experiences several issues where the device will randomly disconnect when uploading and debugging.

I have wiggled the usb cable on both ends and that does not cause this issue.
I have tried multiple USB cables.
I have tried multiple USB ports.
This is running on my desktop via USB 3.
The CPU is not reset when this disconnect and reconnect happens

It appears at least when uploading it should disconnect and reconnect once but sometimes when it does it gives a j-link error:

------Target related settings------
Target device: FE310
Target interface: JTAG
Target interface speed: 1000kHz
Target endian: little

Connecting to J-Link…
WARNING: Out of sync , resynchronizing…
WARNING: Out of sync , resynchronizing…
WARNING: Out of sync , resynchronizing…
Connecting to J-Link failed. Connected correctly?
GDBServer will be closed…
Shutting down…
Could not connect to J-Link.
Please check power, connection and settings.

One issue I am experiencing an issue where when I try to debug it, it says it reached a breakpoint at 0x0 and the option to continue debugging is greyed out but I can see the LEDs changing so the CPU is running.
It will also just randomly disconnect and reconnect when debugging meaning that I have to restart the gdb session

Sometimes with everything closed but just having it plugged into my desktop it randomly disconnects and reconnects.

I have not found a way to reliably reproduce these errors but waiting long enough and re-running enough times does reproduce them.
Any help would be appreciated, thanks.