Today I’ve chosen to blog about Oracle database licensing policy for two reasons. Set one display’s switch to have CS1 on , and the other to have CS2 on. If your displays light up the wrong way round, just swap their identities using these switches. If you have a webbased application where you can not really count the users you have to license by processor anyway.
Make sure the displays are set to CS1 and CS2 with the switches. I have a server with 2 physical Xeon X5550 Quad Core Processors and a maximum of 200 users. But sometimes one of the displays goes out or flashes. I switched the displays and arduino stand-alone board to one supply and it works great.
The displays use a serial protocol called SPI to receive data. Also check the clock is ticking, the arduino pin 13 LED should flash once a second. I have added PIR control to turn the displays off when no one is in the room, master Clock sync, a DS3231 module, remote control and a few other tweaks.
Also check you have the new version of the display board with the chips on the back. For example, licensing Enterprise Edition on a single EC2 instance of 8 virtual cores (platform with core processor licensing factor of 0.5) would require 8 0.5 = 4 processor licenses.
It has been a while since I have used a board that I did not build from scratch, but I seem to remember there being an LED blink in the sketch, which serves as an indicator that the clock is there and working. So you either buy 4 Processor Licenses or 100 Named User Plus licenses if you can count an name all users, machines, sensors or whatever (they are all users) and the total number is up to 100.