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crez

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Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 01:35pm 16 Apr 2016

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I need to display color text on a large lcd screen controlled by a micromite. I have been experimenting with a color maximite, but the text size I need is smaller than the largest (limited character set) font and the second largest one. Ideally I would like to specify text color, text height and text position. I was originally planning to make 80mm high seven segment led displays but the lcd panel would be more flexible. Perhaps there is a Raspberry-Pi solution out there. Any Ideas?

David

CircuitGizmos

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Joined: 08/09/2011
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Posted: 02:16pm 16 Apr 2016

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crez said I need to display color text on a large lcd screen controlled by a micromite. I have been experimenting with a color maximite, but the text size I need is smaller than the largest (limited character set) font and the second largest one. Ideally I would like to specify text color, text height and text position. I was originally planning to make 80mm high seven segment led displays but the lcd panel would be more flexible. Perhaps there is a Raspberry-Pi solution out there. Any Ideas?

You can make your own font or draw text by drawing the characters. You would need to work out the graphics to make each character, however.

rPi might be easier. I have a display setup that blanks the entire rPi screen and fills the screen with text adjusted rather easily to the size that I need. Use any font (native or added to the rPi Linux OS) at scale-able sizes.

Micromites and Maximites! - Beginning Maximite

crez

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Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 03:38pm 16 Apr 2016

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Thanks for your reply. I am new to RPi. can you give me a few more details or direct me to some 'required reading'. It would be good if it would boot from power-up into a mode where it receives serial input with text and formatting info and displays it.

David

bigmik

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Joined: 20/06/2011
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Posted: 03:43pm 16 Apr 2016

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Hi David,

Have you looked at my Mik-Matrix

Which is an LED moving message board display..

Currently the software is moving text only and as it is written entirely in MMBasic (no C functions) it is very slightly jerky but Curtis, (the designer of the original concept) has been worrking furiously teaching himself C from scratch and has already come up with some great CFunction based code that allows for static message and smooth scrolling and whilst that demo is not yet released as he has a few bugs to sort out it is really good (I would say EXTREMELY good) and could be an option for you..

The boards are made to suit a 32mm LED matrix display but there is no reason you couldnt run wires to larger panels (pinout would most likely differ) if you wished..

I think the maximum supported panels (8x8 matrix) is pretty high (around the 30 mark) but Curtis could probably confirm on that one..

Anyway it is one option

Kind Regards,

Mick

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

Justplayin

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Joined: 31/01/2014
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Posted: 07:16pm 16 Apr 2016

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bigmik said I think the maximum supported panels (8x8 matrix) is pretty high (around the 30 mark) but Curtis could probably confirm on that one..

Last time I tested it I had a theoretical limit of around 120

, but that was before the latest additions. It's late here, I'll retest it tomorrow using the latest code.

--Curtis

I am not a Mad Scientist... It makes me happy inventing new ways to take over the world!!

bigmik

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Posted: 07:32pm 16 Apr 2016

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@ Curtis,

Justplayin said Last time I tested it I had a theoretical limit of around 120

Crikey!!!! Is that all.

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

crez

Senior Member

Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 09:29pm 16 Apr 2016

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I did look at the Mik-matrix and decided that the character size would be too small. The display needs to be read at 80kph or 22m/s, so if you need 2 seconds to read it, it must be large enuf to be read at a distance of about 40m.

kiiid

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Joined: 11/05/2013
Location: United Kingdom
Posts: 671

Posted: 10:27pm 16 Apr 2016

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Are you going to be displaying numbers or text or both? In how many lines, how many characters per line?
I have done similar thing a few years ago, and 4" segment indicators are perfectly visible from about 150m distance, which at speed 80kmh (or 22m/s) would give you about 7 seconds time to read, which is plenty. I think there are even larger segment indicators, and you can negotiate with manufacturers to make a custom one with RGB LEDs.
This will be easier and much more cost-effective than large matrix displays.

http://rittle.org

--------------

bigmik

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Posted: 10:33pm 16 Apr 2016

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Hi Crez,

Understood.. Mik-Matrix probably not a good fit given those requirements..

Now....

You could of course use high current drivers and make your own displays from LED strip lights.. Depending of course what you wish to display... If in a 7 segment format that would be pretty easy you could make them 12" high..

Kind Regards,

Mick

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

crez

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Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 12:48am 17 Apr 2016

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The original plan was to make my own 7 segment displays with maybe 6 led's per segment and a character height of about 80 to 90mm. The format is to be mm:ss.s where m is minutes and (you guessed it) s is seconds. A total of three of these for fastest lap, slowest lap and most recent lap. I have TPIC6B595's (I think that is the number) to drive the segments.
That was for 1 rider/driver. There could be several. That's a lot of soldering of individual leds. I'll have to have another look for large 7 seg displays.

I had another play with the maximite with custom fonts until I found that I was not going to be able to make full use of the width of a widescreen display. (someone correct me if I am wrong)

I haven't given up on the Raspberry Pi receiving serial data and driving the large lcd screen yet. Its just unfamiliar territory, but should be feasible. One downside of this is the need for a 240vac supply for the screen.

Bill.b

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Joined: 25/06/2011
Location: Australia
Posts: 235

Posted: 12:50am 17 Apr 2016

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Hi David

have a look at these displays from Jaycar.

http://www.jaycar.com.au/Kits%2C-Science-%26-Learning/Electronic-Project-Kits/Computer-%26-Programming/Red-LED-Dot-Matri x-Display-for-Arduino/p/XC4621

or http://www.freetronics.com.au/products/dot-matrix-display-32x16-red#.VxNtFs5OJhH

BillEdited by Bill.b 2016-04-18

In the interests of the environment, this post has been constructed entirely from recycled electrons.

5bar
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Joined: 10/07/2014
Location: Australia
Posts: 16

Posted: 01:20am 17 Apr 2016

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Maximite does do composite video output, tho I've never tried it
only limitation then is the screen size
worth a try?

Cheers, Lin

I can count to 31 on one hand

bigmik

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Joined: 20/06/2011
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Posted: 02:14am 17 Apr 2016

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Crez,

Of course large 7 segment displays exist..

These seem pretty cheap..

4" display

Regards.

Mick

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

MicroBlocks

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Joined: 12/05/2012
Location: Thailand
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Posted: 02:23am 17 Apr 2016

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You could cut some wood/acrylic in the shape of a 7-segment display and use some LED strips for each segment. You could make it any size you want.

like this:
https://www.youtube.com/watch?v=I0RlI3B1lqA Edited by MicroBlocks 2016-04-18

Microblocks. Build with logic.

5bar
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Joined: 10/07/2014
Location: Australia
Posts: 16

Posted: 02:30am 17 Apr 2016

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One thing not mentioned so far
does this require visibilty in strong sunlight?

I can count to 31 on one hand

crez

Senior Member

Joined: 24/10/2012
Location: Australia
Posts: 152

Posted: 03:45am 17 Apr 2016

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Thanks everyone for your valuable input. I have a number of leads to follow. The freetronics panel look interesting, but I haven't got my head around how to address it yet. I can't just drop in the arduino libraries. 5bar, the display has to be visible in daylight but only from a 40 degree angle, so a sun shade could be part of the setup.
Now I need sleep. I'll post my progress later.

hitsware
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Joined: 23/11/2012
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Posts: 535

Posted: 05:44am 17 Apr 2016

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5bar said Maximite does do composite video output, tho I've never tried it
only limitation then is the screen size
worth a try?

Cheers, Lin

A DuinoMite would be handier
(having the composite out RCA already on the board)

5bar
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Joined: 10/07/2014
Location: Australia
Posts: 16

Posted: 06:29am 17 Apr 2016

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CGMM I purchased had RCA socket and lands on the board (I think)
Too dark to check now

just another thought along the homebrew LED strips
what about 11 segment displays?

I can count to 31 on one hand

5bar
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Posted: 06:32am 17 Apr 2016

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Sorry, double post
damn phone locked upEdited by 5bar 2016-04-18

I can count to 31 on one hand

MM_Wombat
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Joined: 12/12/2011
Location: Australia
Posts: 139

Posted: 12:04pm 17 Apr 2016

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@ Crez

I wrote an updated firmware for the B/W Maximite firmware version 3.2 that output part of the screen display directly out to the Freetronics led panels. You just drew on the upper left portion of the screen and an interrupt would call a routine to draw to the panels. That way you just had to keep updating the screen. I had 9 panels in a 3x3 matrix which displayed 96 pixels wide by 48 pixels high. I even had a small space invader moving back and forth across the screen.

This is the thread, Here

I could assume that a cfunction could be written for the Micromite.

MM_Wombat

Keep plugging away, it is fun learning
But can be expensive (if you keep blowing things up).

Maximite, ColourMaximite, MM+

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