Can I interface multiple 4 char matrixes / alphan?

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi there
im building a custom sign where i need 3 x [12 alphanumeric character] displays.

i.e. i need to display words and numbers in 3 different areas on the sign board, so 32 characters in all.

Can the arduino handle this. I also have a mega

I need to do this times 9:

im looking at:

RS Stock No. 654-1850 Manufacturer OSRAM Opto Semiconductors Manufacturers Part No. PD 3537

or

HDSP-A47C (http://uk.farnell.com/avago-technologies/hdsp-a47c/led-display-starburst-4-digit-cc/dp/1003351)

is there an easier or more suited dislay for me to use? Maybe one that is already quite long?

this is my first display project but not my first arduino project. Ive built servo robots before.

thanks!

2

thanks for your reply
please forgive me if youve answered this in your previous post,

Can i address lets say 3 of the 4 char units together and do that 3 times?

So i have 3 separate areas of 12 chars where I can send text.
Im making a sign sort of like this

And can you tell me the difference between 74LS164 and HEF4094 shifters?

2b.
and of these shifters:
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=74HC595&x=0&y=0

Which one of 4, 5 and 6 is the right one? Is the difference merely, Fairchild, Philips and ON Semiconductor?

It seems the one you recommend is only surface mount?

im new to this shifting malarkey
thanks again
very kind of you to reply ;D

And is 'The Agilent display' the unit that we are talking about?
sorry again for my dumbness. (im an artist ! )

3

Great,
thanks so much for all your expertise,
I have decided to go with the Agilent units because they are bigger and size is an issue with this piece.

Do you know if i want common connection annode or cathode?

I have also ordered the Driver chips.

I will read all the tutorials you linked me to and probably get massively stuck along the way and beg for help

Thanks again

4

Do you know if i want common connection annode or cathode?

If you are using shift registers to drive them, then you need a common positive connection, so that would be common anode.

A shift register like the 595 is designed to sink current (connect it to ground) rather than source it (connect it to +ve).

However have you considered how many shift registers you will need? It will be two for each digit. You can reduce this by multiplexing but you will then need some anode drivers like a transistor or FET.
Before you order anything make sure you have a schematic that stands a chance of working.

5

Eep!

I have ordered 12 Common Cathode:
http://uk.farnell.com/jsp/search/productdetail.jsp?SKU=1003351

and 10 LED drivers:

are these guys not going to talk to each other? :frowning:
Do i really need 2 of these driver/shifters per digit!

Can you tell me exactly what to order?
Or what driver/shifters i need to drive what i have already ordered.
Do i need resistors to each LED in the unit?
That would be amazing.

I need 3 lines of 12 characters (36 chars)

Thanks so much by the way.

6

There is always the MAX6954 chip which will drive 8 digits worth of 16 segment displays but they are expensive.

7

so if I want to run 36 characters I need 72 of these Driver chips?!
Blimey. If its within budget should I just buy the Maxim drivers? is that easier?

Are you aware of an LED matrix version of what Im doing that would be more economical / easier / practical? (see image in 3rd post)

I dont really mind if its matrix or starburst.
I just need the characters to be 2cm or so in height.

I was trying to avoid scrolling text, but maybe 3 pairs of these:
Sure 2416 or 0832
would be easier? But i have no idea where to buy them in UK at short notice.

thanks again.

8

An LED matrix would be more difficult to control as you then have a lot more LEDs to control. However an intelligent LED matrix would suite.
I got some of Ebay a month or two back for only £2.00 but I think they have gone now:-
DLR1414 Four-digit 5x7 LED dot matrix display module
They are about £20 new from:-

They might be too small for you.
There are other alternatives try searching the Farnell site.

You are probably better going for back lit LCDs

[edit]What about something like this:- http://cgi.ebay.co.uk/0832-Dot-Matrix-Green-Display-Information-Board-/250687108574?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item3a5e1db5de[/edit]

9

If its within budget should I just buy the Maxim drivers? is that easier??

10

There are about 10 threads here in this forum about the Sure Electronics displays; they also come in 16x24 or other layout, as they use any number of 8x8 matrix displays. Of course I also own one of them :wink:

Difficult to say what they are worth.. Read through those 10 threads....

11

If indeed you are referring to:

indeed, grumpy mike is a legend. But the only problem is that the characters are only 5mm high.

And what im making is a public-ish signboard.

And if im gonna use these Sure boys. Can i do more than four? All the posts seem to have 4 as the max. Can i use a Arduino Mega for 6 or 9?