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17-Jan-2020 The PCB is in revision 2, and the code is basically complete. The Current design will drive 1 - 2x5 panel, or 2 -1x4 panels displays with either 1/16 scan or 1/8 scan organization. Two different 1/8 scan types (something and version 2.0) are supported. The displays can be inverted via software for easier mounting.

The current parts cost for a 2x5 big display is ~$340 for everything except an enclosure. This includes all the shipping costs. This is ready to go except a data cable and a 12 volt supply (usually a car battery).

The system uses these displays for now OS-P6-32X32-8S. The actual part number stamped on the panel is P6-3535-8S-HL2.0. The controller is a STMicro Nucleo-F446RE board. This is mounted to a custom PCB to make the connections to the panels, the RS485 receiver, and the optional XBee radio.

The RS485 receive is a small board that is available from Amazon or other vendors. For example : https://www.amazon.com/gp/product/B00NIOLNAG/ref=ppx_yo_dt_b_asin_title_o08_s01?ie=UTF8&psc=1

The software is built using IAR EWARM 8.42.1, but is readily adaptable to the STMicro System Workbench. I may do this when when I have time. The display takes input from 3 inputs all the time. Input 1 is the RS485 board @9600 baud 8N1. Input 2 is via the XBEE, also at 9600 8N1. Finally logic level serial is accepted on the 6 pin header at 115.2 kbaud, 8N1. This is a 3 volt logic level input that matches the FTDI 3V3 USB to serial cable. (PN TTL-232R-3V3, https://www.ftdichip.com/Products/Cables/USBTTLSerial.htm). However any 3 volt serial data will do if you have some other kind of cable. My preference is the RS485 option because it allows for a long cable between the controller/PC and the display that has only a two wire interface with no ground. This isolates the electrical noise from the PA system. It's easy enough to solder a FTDI cable to one of the little 485 boards to make something that works from a laptop and allows the actual display to be a long distance away. Optionally there are many radio solutions for transmitting the data remotely.

The firmware in the controller accepts three protocols, the MBT native protocol, the legacy GliderScore protocol and the new GliderScore protocol. To configure the display as one big display or two small ones, or to switch orientation or panel type the blue button is pressed. Each time it is pressed it repaints the display with a test display. Once the correct configuration is selected, a greater than 1 second press and release will commit the configuration to internal flash and not need to be done again.

More details to follow.