Alpha 220 LED Sign

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Revision as of 22:30, 9 August 2007

I am using my Kuro Pro to drive an Alpha 215/220 LED Display I happened to have one of these signs lying around.

220 Full Matrix, (Case 37.7" x 3.8" x 2.9 ") Tricolor[1]

Install a Serial Port Interface

First you are going to have to install a serial port interface. I ended up installing mine to the serial port on the bottom, but the serial port on the front is easier and the same.

I used a board from futurelec, they are dirt cheap, but take forever to get to you

http://www.futurlec.com/Mini_RS232_TTL_3V.shtml

I used a Quick port RJ-12 jack to interface the sign to the serial port converter

Then I shoved the whole thing in a 2 port Quick port surface mount housing

Interface Sign to Serial Port Interface

I used a standard 6 wire telephone cable meant for a two line phone (a 4 wire one will not work) Plug one end into the sign. And one end into the Quick port RJ-12 Jack Wire the jack into the serial port board as such^[2]

• Pin 4 of the RJ12 to RS-232 RX.
• Pin 3 of the RJ12 to RS-232 TX
• Pin 6 of the RJ12 to RS-232 GND

Setup the serial port

You will have to adjust the serial port settings. I use a script to do this. My information came from a FAQ on using the Alpha sign with Linux^[3].

setledsign

# /usr/local/bin/setledsign
#!/bin/sh

rm /dev/alpha
ln -s /dev/ttyS0 /dev/alpha
chmod a+rw /dev/alpha
stty 9600 -opost -ocrnl -onlcr cs7 parenb -parodd < /dev/alpha

Wake up the sign and display something on it

I use a script that I stole from the above site.

alphamon.pl

# alphamon.pl
#
#!/usr/bin/perl
#
# Script will display the contents of /tmp/textfile to the ALPHA 220C LED
# Display
#
# Usage
#
# alphamon.pl [MODE TAG] [COLORTAG]


# Get the attention of the sign
print "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";


# Tell the sign to print the message
$message = `cat /tmp/textfile` ;

print "\001" . "Z" . "00" . "\002" . "AA" . "\x1B" . " $ARGV[0]" . "\x1C" . "$ARGV[1]" . $message . "\004";

Alpha Sign Syntax

"\001" . "Z" . "00" . "\002" . "AA" . "\x1B" . "t". "\x1C" . "1". Hello World . "\004"

MODE TAG and COLORTAG

The key parts of this are the MODE TAG and COLORTAG, there is full documentation available for this^[4] but here are the pertinant parts.

Stock Ticker

I do use the sign for a number of other purposes, to display RSS feeds and weather forecasts. But the most complicated script is to display a live stock ticker that gets it's data from yahoo. It then colors the prices green if they are positive/up and red if they are negative/down for the day.

First you should install perl and make

apt-get install perl make

Then install the quote package ^[5]

wget http://www.circlemud.org/pub/jelson/quote/quote-0.05.tar.gz
tar -xvzf quote-0.05.tar.gz
cd quote-0.05
./configure
./make
./make install

you may as well install curl and lynx so that you can use them to get content from the web later

apt-get install curl lynx

Lastly here is a shell script to display the ticker

leddisplay

# /usr/local/bin/leddisplay
#!/bin/sh
# Stock ticker symbols
#
PTE=/usr/local/bin

stocks="  ^DJI ^IXIC ^GSPC "

        quote $stocks | cut -d"(" -f1 |sed 's/^/\x1C9 \x7F \x1C3 /' | sed '/ -/s/:/\x1C1/g' | sed '/ +/s/:/\x1C2/g' > /tmp/textfile
        $PTE/alphamon.pl t A  > /dev/alpha
  

References

1. ↑ 220 brochure (Pdf)
2. ↑ Building a Data Cable for Alpha LED Scrolling Signs
3. ↑ Using the Alpha 215C with Linux
4. ↑ Alpha Sign Communications Protocol (pn 9708-8061)
5. ↑ quote -- command-line stock quote display