Mark decided to work on the Flash display drivers this weekend to finish populating the cards. He is now done, and has tested the boards and they all display. I know I like pictures so here are some.
Here is the board taped with the Kapton stencil. The stencil reduced the amount of time to populate the boards significantly. The second picture shows all of the boards populated. That would be 4 player boards, and the master display board.
One thing to watch for is solder bridging especially around the dual channel FETs for driving the segments. Here is a picture of two solder bridges that needed to be fixed.
The short is the small bit of solder between the bottom three pins. This is a highly magnified picture and a little touch with some solder wick and a hot iron fixed this right up. It was relatively easy to find these shorts because the LED segment would be fully on. Here is a quote from Mark: “Used solder mask for first time, easier to apply paste although the thinner cross section did not reflow as well leaving numerous shorting bridges. Fixed with scalpel under microscope and retouched each lead with soldering iron to reflow.”
Using the stencil is a lot faster, but there is still a learning curve. Here is the final picture of one of the displays being powered by the Flash machine.
You can see some of the debug info built into the code. At initialization, the master card discovers the displays on the i2c bus. It then either prints the display number that it found, or prints a 0 to indicate the display is missing. In this case, only display 1 is plugged in, while display 2, 3, and 4 are missing so they are reported as 0 on the master control board.
The cables haven’t been finished yet, but that should happen later this week. Pinball night is moving to Wednesday because of scheduling conflicts, so maybe we can actually run a couple of games and be able to see how many credits, and which ball the game is on.
The displays are very bright, and I think that we are both pretty happy with how they are coming out. I’m glad that I added a voltage regulator to allow the displays to be dimmed to the appropriate level. The mounting holes are a little bit small, so these have to be drilled out a little bit to use the original mounting hardware on the Williams game.
Hopefully another post later in the week about it working, but more than likely it will take another day or two to debug the interface to the pinball machine itself.
If anyone owns a Williams Flash game and would be willing to take pictures of their backglass, please get in touch with me. That is the one thing that is really messed up on this game, and I want to do a translite, but the more pictures that we have, the better the translite will be. The backglass on this machine is completely trashed, so any pictures at all would be appreciated.