240 x 16 LED Matrix - HELP

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Radarman2

Member
I have inherited a pre-built Large 240 x 16 LED matrix - separated into 3 sub-units cascaded together, the sub-units are then made up of 8x5 LED matrix.
I know something is working as the display shows the welcome screen on startup. From what I can gather, I can load data into the control unit's eeprom and send it control signals to update the display
All attempts via software and serial port have been fruitless except I've managed to register a DSR signal on the serial port. The manufacturers website is a no go, as they won't give me the software without me being one of their engineers.

Anyone ever tried anything like this? I've read some posts that people have made their own and if it comes to it I will have to take it apart and rebuild it, I would just like to see if I can get it working before I switch to picaxe.
The end result I'm after is displaying alphanumeric characters, no fancy scrolling/flashing/animation at all.
A pointing finger or gentle push in the right direction would be gratefully received.
 
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Radarman2

Member
Sorry, got none of these yet. Rear label says" Moving LED, Model _____", which is really helpful. I can take photos tomorrow. Looks like there's an HD74LS245P for each segment or set of segments. The thing is housed in a 6foot long flat tube and is proving extraordinarily difficult to remove more than about a foot.
Connections: 5 pin row header with 4 wires connected to a serial port: pins 2,3,5 and 8.

Dpne more reading and think I'm going to have to go down the MAX6956 led display driver route (if I could find any)
 
techElder

techElder

Well-known member
How do you know if it even works at all let alone figure out HOW it works?

Is there an ALL ON switch or something like that? Maybe a DEMO mode?
 
W

westaust55

Moderator
@Radarman,

As other have already indicated we need more information.

In view of the comment:
"I have inherited a pre-built Large 240 x 16 LED matrix - separated into 3 sub-units cascaded together"
is this a commercially built unit or something that someone else has assembled? :confused:

You state:
"From what I can gather, I can load data into the control unit's eeprom"
What is the source of that information ?

then you indicate:
"The manufacturers website is a no go, as they won't give me the software without me being one of their engineers."
As Martin has already requested - What manufacturer? - give us a link, name or something to work with (the crystal ball is not working)

Is this the manufacturer of the entire assembly or some part of the total?

How old might it be?

From your comments seems it is an RS-232 interface.
What level are your signal voltages?
Some equipment will work with voltages form 0 to +5V
but I have in the past had some equipment that needed -5V to +5V to communicate (receive data)


Without more information (as already suggested) no one here will have a clue what it is to try and help you.
 
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Radarman2

Member
Sorry folks, was a bit tired when I posted (10 month old does that to you)
To try and answer some questions:

I'll take some photos and post them in a bit.
Looks like it's made by Jayex Ltd and having scoured the site today it looks like it's their D300 805 model. (http://jayex.com/products/patient-call-displays/d300.html). I think the company buys off-the-shelf sub-units and builds their own housing then rebrands as their own system.
Age unknown, but estimate older than 5 years.
It was part of a Medical Centre's patient display system, but system software change rendered it obsolete to them.
Having read a bit about these now, it would appear that the main control board has memory that you pre-load data into and then send control signals if you wish to change the display. This seems to be for animation, standard text looks like it is sent to the unit via RS232. Will need to look up the chips later to make sure.
 
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Radarman2

Member
Right, more details.
Fully housed LED display.
Comprises 6 units:
Power supply (240V to 5.2V twin regulated output)
IR RX board
Control board
LED board.

Control board has a Winbond W78C3 8bit emulation controller (http://pdf1.alldatasheet.com/datasheet-pdf/view/125074/WINBOND/W78C31.html)

NEC D43256BCZ CMOS Static RAM chip x 2

5 pin row header connection serial port cable, terminated in a 9pin D type Female - 9 pin Dtype Male (pins 3 & 5 only) to LAN adaptor - Straight through LAN cable.

Each of the 3 LED boards has a 19 wire input from the Control board as well as the same 19 wires output to the next board (probably data bus).
Qty 32 8x5 LED matrix in banks of 2. (Qty 96 8x5 in total across all boards)
Each LED board has:
ULN2003A (Darlington array) x 12
HD74LS245P (Octal bus transceiver) x 1
HD74LS138P (3 to 8 line decoder) x 2
MC14015BCP (dual 4bit static shift register)

Uploaded 2 photos (2 more on next post) to show it works and the control board.
 

Attachments

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Radarman2

Member
Technical said:
Google is your friend, took 2 minutes:

http://www.pearbright.com/pubs/Jayex_Patient_Call_Displays.pdf
shows the electrical connection and
http://www.jayex.com/images/stories/pdfs/D300%20keypad%20instructions.pdf
says the default baud rate is 9600
Click to expand...
Found both of those, unfortunately doesn't mention where I can get the D300 test software or what data to send to accept text from me. The only thing that shows up is the bloody test message. Also don't have the IR keyboard it mentions.

I think I'm going to end up ripping the control board out, tracing the boards and working out what inputs I need to the transceivers and decoders.
 
E

eclectic

Moderator
Radarman2 said:
Found both of those, unfortunately doesn't mention where I can get the D300 test software or what data to send to accept text from me. The only thing that shows up is the bloody test message. Also don't have the IR keyboard it mentions.

I think I'm going to end up ripping the control board out, tracing the boards and working out what inputs I need to the transceivers and decoders.
Click to expand...
Anything in this link:
http://softwaretopic.informer.com/jayex-d300-tester/

e
 
Technical

Technical

Technical Support
Staff member
We wouldn't give up so easily, RS232 protocols are generally very easy.

We already know from the software instructions
- you only need two wires - receive, ground, connected on the display. So no difficult handshaking or special signals
- 9600,N,8,1 baud rate is default
- each display has a two or four character hex ascii address, and ignores any instruction sent without its address. But you can use ** or **** for forgotten addresses.
- almost all RS232 protocols use CR to finish

so we reckon something like
serout pin,T9600_8,("****hello",cr)
would be a very good start
 
R

Radarman2

Member
The wife knew it was a good idea for me to ask on here lol.
I did use an RS232 port tester with the display - could send ascii and hex, but no rx and no change to the display.
Will try Techies serout example above tomorrow. Cheers peeps
 
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westaust55

Moderator
Some extracts from Jayex data that Techncial linked to:

A typical Jayex installation is usually even simpler: the computer only sends data to the board, and there is no requirement for flow control. Only two wires are needed to:
(a) connect the Transmit Pin of the computer to the Receive Pin of the Jayex Board, and
(b) connect the two Ground pins together.
Click to expand...
Suggests there may be no return data form the display to the PC
Although later in the same document it indicates there are occassions when return data may be required.
 
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russphlp

New Member
Hi there
I have just got one of these up and running so if you would like some help with yours, drop me a reply on here.
Having read your forum I can tell you that you are nowhere close as it is NOT RS232 it is RS 422.
 
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Radarman2

Member
Hi,
sorry about delay - not been on here in ages. I've not got any further with it as I've been too busy with other things, so please send me whatever info you want to about this. I'm hoping to get back into it soon (once I've finished a timing project I'm working on). Did you ditch the main board from this and create a picaxe interface or stuck with the original?
 
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