Product Review: Pro-Lite Scrolling Message Signs

A review of the Pro-Lite Tru-Color II PL-M2014R, an affordable multi-color LED scrolling message board that is capable of being controlled by a standard RS-232 serial port.
Command Syntax

Only a minimal understanding is needed in order to operate the sign. Mastery requires becoming familiar with the protocol and doing a little experimenting.

Multiple signs can be connected to a computer over the same serial port by using a simple telephone-line-splitting Y-connector. Each sign has an assignable logical address that allows you to send messages to particular signs. A logical address is represented in hexadecimal as a number between 01 and FF. Addresses may be shared enabling grouping; in this way, a message to ID01 goes to all signs with ID01.

Communication with the sign is always done with readable ASCII characters; thus, an arbitrary ID of 2F would be designated with the digit “2” and the capital letter “F”.

ID00 is reserved to mean “broadcast to all signs”. By default, a sign is preconfigured as ID01; this can be changed with the remote control. If you are addressing a single sign connected straight to the computer, it will respond with its ID number after each successful command. Messages sent to ID00 do not return a response, and neither does an individual sign when the line is shared via the Y-connector.

All messages to the sign, except for those setting the date and time, are sent in the following format followed by the carriage return/line feed: <IDxx>command, xx is 00 to FF. Any command longer than 1,023 bytes will be ignored by the sign.

To set the date and time, no ID is needed. The format is <TYYMMDDwhhmmss> where YY is the year, MM the month, DD the day, w the weekday (0=Sun, 1=Mon,...6=Sat), hh the hour, mm the minute and ss the seconds. This can be accomplished with the shell very easily. Set the date/time of all signs with the command:

ate "+<T%y%m%d%w%H%M%S>" te "+<T%y%m%d%w%H%M%S>" > /dev/prolite> /dev/prolite

The leading + sign tells the date command to build a string via substitution; see your man pages for details.

To signal a sign to start listening to responses, send it an empty command with the format <IDxx>; e.g., type:

echo "<ID01>" > /dev/prolite

The most fundamental concept of the sign is the idea of a page. A page consists of a message the sign is to display either now or some time in the future. Pages may contain text, numerics, symbols, font attribute tags, color tags, graphic tags and effect tags. There are 26 pages named, appropriately enough, A to Z. Case does matter when identifying a page.

Any given page can hold approximately 1,012 bytes of information. I say approximately because special tags (see sidebar) consume more than one byte, which means less space. Also, using some trickery by omitting the page directive completely and defaulting to page A squeezes out an additional two bytes, which means more space.

The command to set a page is <Px>, where x is the page name. Any text after this sequence is considered text for the sign. To set the message “Linux Rules” on page A, type the following command:

echo "<ID01><PA>Linux Rules" > /dev/prolite

It is important to leave extra space at the end so the end of the message is separated from the front of the message as it scrolls.

To delete a page, use <DPx>, where x is the page name. For example, to delete page B, type:

echo "<ID01><DPB>" > /dev/prolite
Displaying Pages

The sign is constantly displaying a page. If the default page A is scrolling by, then when its content is changed it will immediately start displaying the new message. Otherwise, we must tell the sign which page to run using the <RPx> command, where x is the page to display. Normally, the sign can run only one page at a time.

Once a page has been defined, it can be run. For example, to repeatedly display our message, type:

echo "<ID01><RPA>" > /dev/prolite

Running an undefined page will result in displaying the sign's demo.

Two points of interest for script writers:

  1. It is possible to update the contents of a page not being displayed, then switch to that page at a later time.

  2. It is possible to update the currently displayed message. The only problem is the display will be interrupted mid-message.

Sadly, you cannot ask the sign what the contents of a page are, what page it is currently displaying, or when it has started or ended a display sequence. Thus, techniques like double-buffering don't work for continuous messages.

I have received one terse message from Pro-Lite that alluded to a future version of the sign which is designed to address such needs explicitly for computer users.



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im looking for pro-lite scrolling message signs

tatan's picture

well i want to know if you guys would like to help me.. im looking for a scrollong message signs exacly as the picture that you have on the top
please help i want to buy one of this

scrolling message pc board

Ray Phillips's picture

We are looking to purchase scrolling message boards in quantities of 100 pieces

Scrolling message boards

Guy Tieman's picture

Hello Ray,
My name is Guy Tieman and I work for a sign and mill company. I just stumbled on this site while reseaching a few things and saw your interest in scrolling message boards. We are an OEM of several different LED displays. We are located in Fort Myers, Florida. Our number is (239) 936-9154. If you are still looking give me a call or e-mail me. I might be able to help.
Thanks for your time,


Leon's picture

I have a led board which has 2 lines and 120x16 leds. The protocol described on this page is simular to the protocol used in my led board only it has some kind of security code in it.

For example:
This wil return a ACK, and the led board will show the message:

This wil return a NACK, and the led board does not change:

So there is a code right after the text... Another example:
<ID01><L1><PA><FE><MA><WC><FE>Leon ter Linden1B<E> = ACK
<ID01><L2><PA><FE><Ma><WC><FE>Leon ter Linden43<E> = NACK

Does anyone know how to calculate the code that comes after the text?

xor checksum

Are's picture

Here is the code to calculate the checksum.
The checksum is an xor of all the characters sent, without the first ID tag and without the end E tag.

static unsigned char
checksum(const char *str, unsigned char init)
unsigned char i = init;

while (*str != '\0') {
i ^= *str;

return (i);

main(int argc, char *argv[])
unsigned char csum = 0x0;

if (argc != 2)
msg = argv[1];

csum = checksum(msg, csum);
return (csum);


Are Pedersen's picture

I also have this display. It appears that it is a simple signing pattern, but I haven't figured it out just yet. Finding anything on this on the web seems useless.

Prolite PL - 2111

Anonymous's picture


any reason why there my loader input terminals 14 and R are soldiered together? Will the above work for model Pl 2111 ?

streaming text

jdgalore's picture

I was wondering if any one knows how i can send streaming text to a prolite say text from a news ticker or scrolling music text from musicmatch
? ? ? ? ? ?

Re: Strictly On-Line: Product Review: Pro-Lite Scrolling Message

Anonymous's picture

is there a way to reset the sign to factory?

The graphics are all jumbled.

Re: Strictly On-Line: Product Review: Pro-Lite Scrolling Message

Anonymous's picture

That's the way a Pro-lite sign works.
All jumbled.

Re: Strictly On-Line: Product Review: Pro-Lite Scrolling Message

Anonymous's picture

if you are using serial interface, send a

message to it to erase everything

Re: Strictly On-Line: Product Review: Pro-Lite Scrolling Message

Anonymous's picture


I am trying hard to communicate with my Tru-ColorII and I've had little support from the company. Your explanation, it seems will help me. I wish "a lot".

Thank you

Marcos Ficarelli - Sao Paulo Brasil


Anonymous's picture


Realy congratulations friend.


Re: Strictly On-Line: Product Review: Pro-Lite Scrolling Message

Anonymous's picture

How do I get a new keypad for a Pro-Lite PL4012 or who is a dealer for this product. Thank you..

Re: Strictly On-Line: Product Review: Pro-Lite Scrolling Message

Anonymous's picture

Their Phone # is 1-714-668-9999 or 9998.