AMS 39 Firmware Update Bricked Board

[COVendHut]

Hello All -

I recently started having some 'sensor blocked' errors on a Sensit 3. The firmware was quite a few revisions behind the version that has the drop sensor diagnostics, so I contacted AMS, who provided the latest version for my series of board. I updated the bootloader to the version the AMS support sent me, which completed successfully. The board is supposed to reboot afterwards, but it never did. I let it sit for about half an hour and then power cycled the door.. and that was the last time that either the keypad or display worked.

Not surprisingly, AMS support has gone radio silent on this issue. I'm assuming that I simply need to reflash the firmware to the board, but I am not seeing any obvious connections for a debugger so that I can see what the issue is.  I realize that most people would just do a board swap and move on, but since I know exactly what is wrong with this board, it would be more economical and faster to correct this problem myself. I know this is probably a long shot, but any schematics or pointers for these control boards would shave off reverse engineering time on this board. I'll probably order another board anyway, but I'm going to get to the bottom of this regardless.. I have several other AMS S3s and if I have the same issue on another system, I need to know how to recover from it.

There is also a reference to a Sensit utility that communicates through the DEX port via serial. I built the interface harness, but I'm assuming that the software would be required for me to be able to go any further.

This is an older revision board - 24750.

Thanks for any input or guidance!

 

 

[AZVendor]

I've never heard of updating a Sensit board in that way.  If you have a Sensit 1 machine then you need to upgrade it with the newer Sensit 3 board and sensors.  Updating a vending logic board is typically installing a new eprom with a later version on it.  The method you used is a good way for things to go sideways like it did.  Again, I've never heard of updating a Sensit board that way.

[COVendHut]

It's a Sensit 3, and I followed the manufacturers documented instructions. The firmware is typically loaded via SD card. There is no user removable eprom,

So, basically I contacted AMS before proceeding with anything, they sent me the firmware and instructions. I followed the instructions and after I reported the issue with the update process, support has been unresponsive. I'm finding this typical behavior in this line of business, so I'm trying to help myself and possibly others when they get into a similar situation.

This is probably a topic that is more technical than what is usually discussed here, but I know there are other hardware hackers lurking here and I'm looking for some knowledge share if it exists.

 

[tc vending]

I would just replace the board. However, sensit blocked has to do with the sensors not the control board.

[AZVendor]

Sorry, I missed the S3 reference.  I also forgot that manufacturers introduced this non-fail safe feature to their machines, which was dumb.  Anyway, if it has one, try removing the Timekeeper chip to lose all memory in the board.  Leave it off for a couple of minutes and then turn it on and see if it goes into the default new machine mode with nothing programmed.  If the display comes up then turn it off and put the Timekeeper chip back in and fire it up again.  If none of this works then try to transfer the settings from another working machine to this one (with a blank and freshly formatted card.)  This is the problem with giving operators access to a programming port.  Crane does the same thing.  I am assuming you followed every exact step mentioned in the manual to effect this update.  AMS showed how cocky they are when they didn't think that a diagnostic for the sensors was required.  They just programmed it to ignore the sensors when they messed up.  Not smart.