The first display controller is populated by Mark this weekend. This is the board that will replace the display controller board. As you can see, it only has four digits because the other two digits weren’t used. This is also the only display that will have a micro-controller. All the other displays are simple i2c slave devices with three 16 bit registers each. The jumpers for configuring it as the master display or a player scoring display are on the right side. The connectors on the right are for powering the slave displays.
Here is a picture of the back of the of the board. The voltage regulator/potentiometer allows the brightness of the LEDs to be changed on a system wide basis. The processor is the largest chip on the right, and the two small chips are muxes since the processors doesn’t have enough I/O pins. Only two of the i2c registers are populated since there are only four digits.
We were probably going to bring up this board on pinball night, but Mark now has the flu, so he is probably out for the week. It should be relatively easy to bring up this card and test it over the next few weeks. As soon as this card is up and running, we will build the other four player score cards (which use the same PCB) and we should be done with this project. I’m thinking of making a little wiring harness to make the testing a little bit easier. (Basically a connector with a bunch of pullups/pulldowns so I can simulate the pinball machine sending two characters at a time to this card. I originally thought of doing it using the PCs parallel port, but since there aren’t enough data pins (only about 10 easily accessible), it seems easier to simply make a plug header and move the jumpers by hand.
I’ll probably end up with another entry this week on finishing the initial layout for the Disaster LCD. It is currently streaming video while displaying four players scores. More on that when I finish it up and get to a good stopping place to put it in the repository. I’ve also promised myself that I will throw up the Disaster individual board schematics for the three cards that I have fully tested.
It is rather humorous to read comments about how the blog is centered around restoring pinball machines. I imagine the blog is broken into two different sections: restoration, and then Disaster which is hopefully going to be a pinball machine completely from scratch. While the boards for Disaster are not the most whizz bang designs using the fastest processors, each of the processors is more powerful than the processors that are running pinball machines through the late ’90s.