5V PS/2 Board with no DCS

John,

If you attempted the recover engine function using TIU #1 with a short piece of track directly connected to a working TIU channel with DCS turned on, with no other engines powered up and the recovery failed, then my take is that you're looking a a defect on the board.

Since the loader can't find it, a new sound file isn't a viable solution, either.

Yep, it's on my test bench with a transformer, TIU, and a 40" section of Atlas track.  It doesn't add, and it doesn't show up with the Recover Engine function.  The interesting thing is that it does see the DCS watchdog and come up dark.  If I power the TIU channel and wait a spell and then connect the track, it comes up in conventional as you'd expect.  I tried to add it and Recover it at that point, same issue, no joy.  It sees the DCS signal, just doesn't react to it.

I'm fairly certain there is something amiss with the board, I was hoping against hope that there was some other "reset" that I'm missing.  I did try a conventional reset just for completeness, that didn't change anything.

John,

Actually, there's an animal called a "hard reset", however, I've never had occasion to do one. It involves shorting together two legs on a chip and, I've been told, if you screw it up you can toast a board.

Perhaps someone more knowledgeable, in this regard, than I will come along with additional information.

Well, since the board will have to be replaced if I can't get it running, I'm game.  I have heard this discussed, but I don't know the details.  Perhaps George will come along and tell us both how it's done, I suspect he may have done it.

Barry Broskowitz posted:

John,

Actually, there's an animal called a "hard reset", however, I've never had occasion to do one. It involves shorting together two legs on a chip and, I've been told, if you screw it up you can toast a board.

Perhaps someone more knowledgeable, in this regard, than I will come along with additional information.

My dealer had success with a hard reset with one of my engines years ago. It Wasn't Marty but  Marty F knows about the "hard reset"

However I 'm very  suspicious about software  version 5 and wondering if MTH has also screwed up the recover engine feature.

I'm assuming you tried a Remote reset just in case of ID conflicts. The loader should have found the engine.

Since this is my test bench setup, I have no significant configuration stored.  I did a remote reset, then a TIU reset, none of that changed anything.  I even tried another PS/2 engine to make sure the rig was all working. 

I'd like to find out about the hard reset, that seems to be about my "last gasp".

I'm curious what version of the software you're using?I know how to test the recover engine feature  with version 4.xx  to see if it's working but I'm afraid to test it with version 5.

John, years ago a few of us were taught a procedure  MTH called a hard reset.  It can not be explained but it usually works on a board like yours.   This has nothing to do with recover engine.  If you want to send me the board, you may get lucky.

This is not printed anywhere except in my notes.  It works on 5 and 3 volt boards.  Not something MTH wanted outside the shop.

It involves shorting 2 legs of the processor chip and is hard to get to. It can only be shorted for a brief moment or the board is toast. If you try it a Xacto knife works well.

Chuck, that is why MTH insisted we not pass that proceedure on as many will be cooking boards.  I know you know the legs and you  also keep it in house.  I have had luck with almost every try.  That is a great tool for repair techs.  If you can bring a board back like John has you might make a few bucks, but you will make a friend with it.

Gregg posted:

I'm curious what version of the software you're using?I know how to test the recover engine feature  with version 4.xx  to see if it's working but I'm afraid to test it with version 5.

I tried it on a 4.2 TIU and the 5.0, neither could find it. I have successfully done a Recover Engine using my 5.0 TIU.

Marty Fitzhenry posted:

Chuck, that is why MTH insisted we not pass that proceedure on as many will be cooking boards.  I know you know the legs and you  also keep it in house.  I have had luck with almost every try.  That is a great tool for repair techs.  If you can bring a board back like John has you might make a few bucks, but you will make a friend with it.

I got the process from MTH tech support, and I also got a PDF with the illustrations from another guy. I'd like to bring it back if possible, as it would obviously be a ton cheaper than any other option.

John, I have a board just like that.  Came from an engine that was overloaded and drew too much current.  Most likely the signal transformer or one of the other inductors is shorted and killing the DCS signal.  Problem is, you can't get to them.  G

Well, the customer elected not to pursue any repair options, so he's getting it back the way it came.  I'd have liked to tried the reset, but he didn't want to risk killing it totally, a viewpoint I can understand.  I'll never know if the reset would have fixed this one.

I have no interest in knowing how to do the "unexplainable" hard reset, or which 2 legs are involved, but I'd be interested in learning from one of our electronics whizbangs just what such a shorting of terminals does.

Apparently, it forces a bad read of the data and thus a checksum error.  That would cause the board to load the factory defaults and correct any parameter corruption.

Before the day of recover engine on the remote, if a 5V had an outer parameter ID # there was no way to recover it in DCS.  THe hard reset would do this and change the address back to 1.  It seems to help in some other conflicts too, but I have had limited success with it.   G

Well, that one was solved by no action, but I am going to keep the hard reset in mind in the future.  This is the second time I've run across the "runs perfect in conventional" and not in command.

Thanks for the info, GGG & GRJ.

FWIW. I have an engine that was saved many years ago with this procedure as far as I know. Jeff told my tech at the time how to do it. 

I'd have liked to try it, but he didn't want to risk it killing the board.  I was told that there was a chance the board didn't come back, so I pretended I was practicing medicine and told him about the risks.