Thanks for the reply, Manu. The thing I don't understand about your explanation, though, is which cable are you saying has the crosstalk issues? The USB cable or the cable between the ICD2 and the PIC? I would have thought that all the timing in the ICD2<->PIC cable would be handled by the ICD2, not the PC, so I don't understand why changing software on the PC would affect it. If the issue were with the USB cable, then adding RC filters to the ICS2<->PIC connection should have nothing to do with it. Sean On Mon, Jan 1, 2018 at 3:45 PM, Manu Abraham wrote= : > Hi Sean, > > Two statements made me feel it's the timing. With the 3rd it was even > more evident. > > The old machine: > > "Apart from the usual idiosyncrasies > associated with Microchip products it serves me well even if it is a bit > slow compiling." > > The new machine: > > "Earlier this year I bought a used Thinkpad laptop running Windows 8 (32 > bit) and decided to use that as my lab machine since it was newer and > faster and took up less desk space. So I installed MPl8.92, shifted t= he > ICD2 and set about programming. Unfortunately programming under the > debugger fails with the ICD0083 message." > > How he got it working on the new machine: > > "But today my son, visiting for Christmas, installed > something called Virtual Box which allow me to run XP in a window on the > laptop And to my amazement I can use MPL8.92 successfully in this > scenario." > > This is what I understand: > > #1. The old machine was slow and the I/O on the cable was okay. > > #2. The faster userspace I/O on the newer system, caused a higher data ra= te > on the cable, which directly affected crosstalk. This broke communication= .. > > #3. Now, the faster machine has a virtual machine, which slows down all > I/O. > App->VM->OS->USB->serial in comparison to App->OS->USB->serial > > (The additional introduction of the VM makes things working for him: all > his > I/O is now delayed. Indirectly, it implies the same issue that the edges > are > too fast for his cable. He needs to slow down the edges. :-) > R-C filter to damp it ? :-) Does that work ? points to FEXT, I must say) > > In my situation, I had an even more funnier situation. The machine was th= e > same, but if i used a newer cable it would work for a few days. That cab= le > would behave exactly the same as the old one. Cable had no issues. > Eventually, I figured out that humidity and physical handling the cable a > few times had some effect to the cheap chinese cable. Likely the cable > behaved like a Transmission Line (?) with an increasing capacitance over > time due to a myriad factors. > > Userspace drivers are okay if done correctly. But when userspace drivers > are available, it gives the user a chance to make clumsy stuff. But where= as > an in kernel driver, if you do that, everything blows apart. So, the user > is > forced to write good applications in case of a kernelspace driver. The > downside is that a kernelspace driver is more difficult to handle in > comparison. This is the prime reason why the Linux kernel drags people > to go with kernelspace drivers instead of userspace drivers. > > > Cheers, > > Manu > > > On Mon, Jan 1, 2018 at 10:16 PM, Sean Breheny wrote: > > Hi Manu, > > > > I never heard the term NEXT/FEXT before and when I Google it, it seems = to > > be talking about physical crosstalk. What does that have to do with the > > timing issues you mention? > > > > Just trying to understand! Thanks. > > > > Sean > > > > > > On Mon, Jan 1, 2018 at 10:26 AM, Manu Abraham > > wrote: > > > >> > >> https://msdn.microsoft.com/en-us/library/windows/hardware/ > >> ff540207(v=3Dvs.85).aspx > >> > >> WinUSB is a User Mode Driver framework, Kernelspace drivers comply mor= e > to > >> timing restrictions etc etc.. So, the userspace timing dictates your b= us > >> timing. > >> This is dictates your Near END/ Far END (NEXT/FEXT) crosstalk. IIRC > >> correctly, > >> I've gone through this specific problem. Olin Lathrop has had a > >> suggestion for this > >> issue on this ML, a long time back. This did fix the issue for me. > >> > > -- > > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > > View/change your membership options at > > http://mailman.mit.edu/mailman/listinfo/piclist > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .