LED Display Sign

This C project has three components:

• A dot-matrix display sign formatter with an 8px ASCII font
• An e-mail inbox interface for posting messages on the sign
• A display sign controller for scrolling through the available messages.

Dot-Matrix Display Formatter (LDF)

The command-line formatter was written to produce bitmaps for a frickin' laser display but the format of the .LDM binary bitmap files can be adapted for off-the-shelf LED displays instead. (Our laser display had optics to scan and modulate an 8W laser over a 1024x24px bitmap but we did not have the money or safety clearence to use it with a laser any more than a few mW.)

E-mail Interface (LDF3)

Messages are posted to the display sign by emailing them to the sign's email address. Because SMS also uses SMTP/POP3 it is easy to convert this to an SMS interface but you will also want to simplify the TROFF-like syntax of the message for SMS users.

Sign Controller (LASER)

This component is written to drive our awesome 8W laser display attached by parallel printer port to an MS-DOS PC. It scans the contents of a directory for .LDM files and using their .FR(om) and .TO times and .PR(iority) settings builds a playlist of messages to scroll through on the display sign. It adds stock 'house' messages to the playlist if there is nothing else to display.

Utilities

• VIEWLDM prints the contents of a .LDM (Laser/Led Display Message) file to the console.
• STDMESS/ direcory contains the stock 'house' messages
• TEST/ directory contains some example messages
• LINEUP is a utility you won't need with an LED display sign. (It was needed with our laser display prototype to compensate for imperfections in the milling of the raster-scanning reflector surfaces and determine the values of lineorder[] and lineoffset[] arrays used by set() in LDFBMAP.C to correct to the actual geometry of the scan pattern.)

User Guide

https://raw.github.com/rfinean/led-display-sign/master/HELP/README.TXT