Forgetful TIUs

We have 9 tiu’s and occasionally our variable ports go back  to variable instead of fixed.  I was blaming it on user error

My workbench TIU this last week did that!

It was ID 5, then it became ID 1.   Thought I was going crazy till I figured out what happened.  Keeping a eye out to see if it re-occurs.

Rev L.

Jim

What revision are y'all's tiu's

@Jim Sandman posted:

My workbench TIU this last week did that!

It was ID 5, then it became ID 1.   Thought I was going crazy till I figured out what happened.  Keeping a eye out to see if it re-occurs.

Rev L.

It sounds like some of Adrian's TIU's are resetting every power cycle!

@gunrunnerjohn posted:

It sounds like some of Adrian's TIU's are resetting every power cycle!

Consistency is good...  Debugging those every now and then issues are maddening.

Mine has been forgetting Var 2 is fixed for about a year now. Not always but more than 70% of the time.

@Jim Sandman posted:

Consistency is good...  Debugging those every now and then issues are maddening.

I'm not sure it's good in this case, it's likely it's one of the big chips that only a SMT rework house could replace.

@Rod M. posted:

What revision are y'all's tiu's

Rev L latest 6.1. They were fine for 6 years, but now suddenly 2 of them are very forgetful. 1 more is occasionally forgetful, the other 2 never forget (yet)

@gunrunnerjohn posted:

I'm not sure it's good in this case, it's likely it's one of the big chips that only a SMT rework house could replace.

There's an flash memory chip on the PCB (M29DW323DB) which is near the radio board. I assume this is what they use to store the settings in a non-volatile fashion. I could smuggle the TIUs into work and change that part pretty mindlessly with some modest SMT and hot air effort. The catch is ...  is there other stuff preloaded on there too? Like if I lift the part off the PCB ... What I'd worry about is something like

0000 to 00FF is preloaded with the bitstream/bootloader for the Xilinx Spartan FPGA that loads onto it when the TIU boots. Only done one time at MTH's manufacturer prior to the part shipping

01FF to 0FFF programmable settings the FPGA writes based on commands from remote/WIU/wherever

--> So if I lift the part off and replace it that 0000 to 00FF part isn't there anymore and it won't boot.

It does say it's good for 100,000 cycles but who knows

https://www.digikey.com/htmlda...1/m29dw323db-dt.html

Tricky stuff.

@Adrian! posted:

There's an flash memory chip on the PCB (M29DW323DB) which is near the radio board. I assume this is what they use to store the settings in a non-volatile fashion. I could smuggle the TIUs into work and change that part pretty mindlessly with some modest SMT and hot air effort. The catch is ...  is there other stuff preloaded on there too? Like if I lift the part off the PCB ... What I'd worry about is something like

Honestly, I have no idea where they store the settings, but that seems like a reasonable guess.  FWIW, I wouldn't expect them to store just those few parameters in a 16MB chip, I'm guessing the actual program is in there as well.

I replace that chip multiple times on Rev G TIUs that have lost ability to retain an address between 1 and 5.  So replacing it is no issue as long as you match it and memory size.  32 meg need a ground jumper on the early 16m memory boards.

I would say try a Factory reset of all your TIUs first.  I just repaired a set that the remote would not consistently talk to the TIU and several soft keys would not work, though others would.  A factory reset on this older Rev G set up did the trick and restored the remote to proper operation.  G

We have the same troubles with fixed/variable on several TIU's. Most are fairly old, been reworked many times by Dave Hikel and 2 flip to TIU 1 quite often.

We have newer ones but are trying to milk it for all it is worth before replace the older ones permanently.

@Adrian! posted:

Rev L latest 6.1. They were fine for 6 years, but now suddenly 2 of them are very forgetful. 1 more is occasionally forgetful, the other 2 never forget (yet)

6 years old?  Doesn't seem like much longevity there. Makes me think of a gremlin as opposed to a faulty chip.

My 15 year old I3's haven't had any issues so was just curious.

I'm to the point where I am ready to remove the TIU.  I have very few MTH engines now, waiting on the new TIU before buying more, so I may just remove it.  It gets annoying to reset the variable channel to fixed randomly.  Like I said this only started happening in the last year.  It also has been having issues loading engines as well and the serial port seems to have failed.  It is the original run of TIUs from when DCS was first announced.  I think it's served me well.

@MartyE posted:

It is the original run of TIUs from when DCS was first announced.  I think it's served me well.

If you're running a Rev. G TIU, it doesn't owe you a dime Marty!

@gunrunnerjohn posted:

If you're running a Rev. G TIU, it doesn't owe you a dime Marty!

That's actually pretty impressive! My original was a rev G. Never had any trouble with it. Jason at MTH had no functioning rev G TIU's to continue testing newer software, he knew I had one and offered a straight up swap for a new at the time I3, I jumped at that.

If anyone has successfully resolved the issue of a Rev L TIU, variable port not holding its setting, please update this tread.  We are having the same issue at our club.  Some of the TIUs which had this issue were only in use for a year or less.

Thanks for any info provided,

Bob D

NJ Hi railers

@rad400 posted:

If anyone has successfully resolved the issue of a Rev L TIU, variable port not holding its setting, please update this tread.  We are having the same issue at our club.  Some of the TIUs which had this issue were only in use for a year or less.

Thanks for any info provided,

Bob D

NJ Hi railers

I'll be a little surprised if this is easily resolved.  Sounds like the memory is forgetting the settings.

@gunrunnerjohn posted:

I'll be a little surprised if this is easily resolved.  Sounds like the memory is forgetting the settings.

I have faith that the three of you (U, Adrain, GGG) will resolve it.  We need to keep these Rev L's working for a while, which have the hand held transceiver boards built in.

Personally, I'll just break out one of my spare TIU's.