HM/DCC P2 Class loco unresponsive after a short run in reverse

[ColinB]

As I said in my post, he can do a few things. See if he has a capacitor in his feed, change his wiring so it is as a star or sections (you should split it up anyway as it can become a big arial) or buy Hornby "stay alive" and fit it. Personally I think the "stay alive" should work. I did do a back to back test with my two P2s one with the Zimo sound decoder in, the other with the HM7K. They both stuttered on my piece of track which is not surprising as it is a frog I haven't got round to wiring up properly, but the Zimo recovered, the HM7K occasionally came back with a bit of movement then sound but no movement. Now it could be me, it appears you all think so, but that is what I observed make of it what you want. My Accurascale class 37 with sound and decent "stay alive" didn't even notice it, but then it seems to retain power for about 10 seconds so why would it.

If there are any English mistakes it is not because I am dyslexic it is because I am an Professional Engineer more used to solving complex issues rather than writing English. Never mind it will raise a laugh at the pub.

[Fishmanoz]

Or he could just check for and remove capacitors in his power feeds then wait for and install the updated sound profile and see if it is all fixed?

As the very, very old joke said “4 years ago, I didn’t even know how to spell injuneer, now I are one!”

[ColinB]

Yes Fishmanoz, very funny most of the guys on my degree course had sat the English O level several times, surprisingly I passed at the first attempt. I notice your post that highlights a very similar fault. Looking at the description of the other fault it appears the latest software might fix this issue. To give credit to you you did say the new software might fix the issue but you didn't highlight that it was a known fault. So you can lock the thread.

[Fishmanoz]

Colin, you are correct, I could have been more explicit.

However, if you look at the first two pages of forum titles, there are multiple topics on each page which relate to the same bug, or family of bugs. And there is discussion in many of them saying it’s all the same fault.

Moving on though, there is now significant new info in the “When will profile issues be resolved” topic saying that the new profiles are now released and it contains a full schedule of them posted by RAF. Further, RAF has now asked in different threads for feedback on whether the specific issues have been resolved by the new profile.

Hopefully, Hornby have a more comprehensive comms strategy to let all customers know, not just those who frequent this forum.

Edit:RAF posted his below before I included paras 3 and 4 to this post.

[96RAF]

Hopefully once the OP and others install the latest profile version all these niggles will have gone away.

[ColinB]

Well I have just tested the v2.0 release on my P2 and it looks like you have it cracked. It performs perfectly no stopping like it used to. So well done. Actually I hate to say but I was quite impressed. Obviously the original poster needs to try it and see if it does fix his issue. It did stall on one of my bits of duff track where I haven't got round to wiring the frog but it recovered whereas previously it would have had issues.

[SteveM6]

I know it's been a long time coming Colin but the performance you have just experienced is a direct result of all the feedback we (particularly RAF96) have been passing back to the development team - they have been listening!

Unfortunately the test team cannot imagine, let alone test, every possible combination of loco/controller/PSU/track configuration the result that some faults only showed up after the general population got hold of the system. As has been said before some reported faults have been difficult to replicate which in turn has made fixes challenging to deliver.

And remember, HM7K is still a work in progress - but you have to admit, it's making good progress.

Enjoy.

[96RAF]

The original temp fix after a loco went dead for no apparent reason was to lift it off track and put it back again, whereupon it resumed operation, so some sort of internal reset must have happened.

As to to details of the magic that happens inside the decoder I have no idea except sight of the schematic, but even then it is a block diagram for the MCU and most other ICs, so no way of knowing what the internal switching is.

Regardless of that the recovery from a track induced interrupt is now self repairing and running is more robust. I can now reliably run a loco off at speed step 1 whether it has a PB fitted or not.

[ColinB]

Reset circuitry on most systems is always an issue, but usually it is the software what you call the start up code where you set up all the interrupt registers, without going into too much detail a lot is to do with setting up the interrupts and all the various ports on the microprocessor, sometimes if it is a "warm start", things don't work as well. I have spent many hours sorting it out on systems where the microprocessor didn't come up properly and then you also have some micros that are damaged and only startup properly every so many attempts. I have a decoder I took out of a loco, sometimes it works, sometimes it doesn't, if it starts up, it runs perfectly. I suspect it got damaged but not enough to kill it completely. That is probably why I got the loco cheap. With my DCC controller you can easily do a reset because it has DCC on and off buttons, on an Elite you just press the Error key and then I think it is the Escape key. Surprisingly my my Rapido loco with a LokSound decoder, well I think that is what is fitted, came up with no sound the other day after it did a reset after hitting a dirty piece of track.

[ColinB]

I know you was Daedalus. I was just highlighting the other issues. They seem to have fixed it so end of story.

[Daedalus]

[ColinB]

Daedalus it is working until the next major concern (we were never allowed to call them bugs), it is acceptable. On the P2 I still think the whistle is a bit distorted but I am no expert, so it is probably me or the speaker. I tried it at all sorts of speeds and it didn't miss a beat so I was happy.