Difference between revisions of "Stern S.A.M. System Repair"

Revision as of 02:55, 7 June 2012


Note: This page is a work in progress. Please help get it to a completed state by adding any useful information to it.

Click to go back to the Data East/Sega/Stern pinball repair guides index.

1 Introduction

S.A.M. is the current board system used by Stern Pinball. The first full production game to use the S.A.M. Board Set was World Poker Tour in 2006. One of the features of the S.A.M. board set is that the software can be updated with a USB stick.

2 Games

3 Technical Info

3.1 The S.A.M. Board Set

The S.A.M. System board set consists of three boards in back box. The I/O Power Driver Board, CPU/Sound Board, and the Display Power Supply.

3.2 Recommended Documentation

As always, it is highly recommended to possess a game manual. Every game manual is full of detailed information regarding game specific switch, lamp, and coil assignments. Equally, details for maneuvering through test, audit, and bookkeeping screen menus, schematics for all boards used, and game specific mechanical assemblies are included. Hard copy game manuals can be purchased through several of the recommended pinball parts suppliers.

The Stern Pinball, Inc. website currently archives game manuals using the S.A.M. in part or in whole in PDF format at the time of this writing.

Stern Pinball also makes Technical Service Bulletins available on their website here. There is an option to search by game title. The archived service bulletins (pre-2009) are here.

3.3 USB Code Update

Note: this information can be found on the front inside cover of S.A.M. System Game Manuals.

Step 1) Open the Back Box
Step 2) On the CPU/Sound board set Dip Switch #8 to "ON".
Step 3) Press the white Reset Button (S1 RESET) or power cycle the game.
Step 4) The DMD should show the current software version installed. Press the "SELECT" button on the inside of the coin door to continue.
Step 5) Highlight the "UPDT" icon on the display and press "SELECT".
Step 6) The game will prompt you to insert the USB Memory Stick.
Step 7) Pick the correct file on the USB drive and press the "SELECT" Button.
Step 8) Follow the directions on the display.

3.4 Accessing Bookkeeping, Settings, and Diagnostic Modes

Placeholder for SAM coin door buttons

3.5 The New Stern LED Lamp System

Stern developed a new serial lamp control system for the release of Tron.

This system uses a serial protocol to control playfield LEDs.

There are three components to the system

  - the serial bus, which carries clock, data, power and strobe signals
  - lamp boards, typically strips, which carry a serial LED controller for on-board LEDs and satellite LEDs
  - LED satellite boards, which solder to the lamp boards.

The lamp boards daisy chain. Therefore, the controller can feed, say, 8 bytes of serial data to the lamp boards and strobe the data in, turning on or off 64 LEDs. This system is potentially expandable to hundreds of controlled lamps, breaking the constraints of the traditional lamp matrix.

The lamp boards and LED boards can be assembled outside the game,simplifying the wiring harness.

The controller used is an STP16DPS05. This device controls 16 LEDs, and uses a constant current output. Therefore, it needs no series resistors, although Stern has implemented series resistors on the satellite boards. [any ideas here?]

The driver is also capable of reporting short and open LEDs, but we do not know if Stern has implemented this feature.

In terms of diagnosis, one failed board could disable the entire system. The STP16DPS05 is a likely candidate for failure if an LED satellite board tangles with GI or other voltages. Replacing the chip is tricky as it has a full-contact heat transfer pad on the underside, which is difficult to heat properly without ot air or IR equipment.

It may also be useful to have a z-connector to hand to bridge out a failed board. This will result in incorrect light patterns, but will at least demonstrate that the system is driving the daisychain.

4 Problems and Solutions

4.1 Power Problems

4.2 MPU boot issues

4.2.1 Relocating the battery from the MPU board

4.2.2 Repairing Battery Corrosion

The Stern S.A.M. system uses a single 3v lithium CR2430 "button cell" for its memory backup. These cells have very long life and are not prone to electrolyte leakage.

4.2.3 Connecting a logic probe to the MPU

4.2.4 Using a PC Power Supply For Bench Testing

4.3 Game resets

4.4 Solenoid problems

4.5 Lamp problems

If you have a bulb not working, seat the wiring into the IDC type socket better. I've run into a lot of these where the wires aren't seated and making good electrical contact.

4.6 Switch problems

If a switch isn't working. The three most common things I've seen is. 1- crappy switch, even if new. 2- if wires go into a IDC connector nearby, be sure they are seated good and making electrical contact. 3- broken wire at switch, or inside casing or harness, easy to quick check continuity of wiring.

4.7 Display problems

4.8 Sound problems

4.9 Flipper problems

Coils hum. The way they are power cycled causes some of this. I've also found that they get noisier with use. I then file the plunger end smooth, and the top of the coil stop smooth, where the plunger hits it. This helps a lot with noise.

4.10 Pop bumper problems

5 References

SAM system schematics are available on the Stern Pinball website here: http://www.sternpinball.com/schematics.shtml

6 Game Specific Problems and Fixes

Stern opto boards at end of trough. And boards playfield optos plug onto. I've noticed when problems arise, to reflow the solder on the optos, and pins the connectors plug onto. This eliminates a lot of problems that arise with the optos. LTG :)

Pirates of the Caribbean. The spinning disc. Check your serial numbers with the service bulletin on Stern's website. Some of the early games need to have the bearings lubricated.

And if your artwork is worn off. I've found when you put on a new decal. To put clear non-slip bath tub stuff on top of it. It works just as good at flinging the balls. And doesn't wear off as fast and get messy all over the game like the original. And easily replaced. LTG :)

7 Repair Logs

Did you do a repair? Log it here as a possible solution for others.

If you have feature lamps not working. Check the wiring pushed into the lamp socket. I've seen more than a few where the wire isn't making good contact where it is pushed in. Easy to push in better. LTG :)