DIY Moving Message Display

[chkhor2005]

moving message display code

Try this.

 

[beny]

running text display source hex

great thanks chkhor2005
it's the same schems i use, only for row drives i use darlington with power transistors, BC548 are not so good for 80 leds on eatch row ! and for resistances i use 27 ohms but 18ohms are better for brigtness, and for columns just a 548 or 547 , very good job chkhor2005 and many thanks.

 

[OBIALOR]

bascom code for led moving display

i will like to have a look at this zip file of yours,meanwhile have a look at this

 

[tdg8934]

diy midi display message led matrix

I stumbled across this site in reference to LED matrix signs. I have designed a couple of homemade ones using Parallax Basic Stamp 2 and more recently their SX-28, SX-48 microcontrollers in their BASIC language. I am not really a PIC user so .... I would like to know where to purchase low cost premade LED matrix modules (and controllers - SPI?) larger than 8x8. I have purchased the 8x8 RGB LED matrix and controller module from www.sparkfun.com and have also used the MAX7219 a few times. Doing a GOOGLE search leads me almost nowheres - always winding up at either a CHINESE manufacturer having to by 10+ at $$ or an LED sign company for indoor/outdoor signs. I have made a couple of 16x16 displays by hand but really want something larger than 8x8 that I can interface to a microcontroller like the Parallax ones.

What are people using?

 

[OBIALOR]

a6821 avr

and another one

 

[tdg8934]

scrolling with pic16f628

I don't understand what you are saying OBIALOR.

Anyway - Mike,

I found this website yesterday and low and behold you were in this post.
Your 7x40 LED display picture to reference (similar but SPI not PWM inputs to the 40 columns).

I have built this using (10) A6821's for (5) BiColored LED Matrix modules. I have been able to write a scanning routine for the SPI inputs on the A6821 for the 40 columns so that data can be shifted into the up/down rows. IS this the correct approach? If I scan the up/down rows then I can never marqee messages in going right to left because the SPI will want me to input a 40 bit stream of data and not just 8 bits on the up/down rows.

Comments?

 

[master_picengineer]

diy 8*8 led matrix

Question:
1- What to do if we have to design a such device but with 140x14 Led.
2- What about If we wanna change the luminosity (or color) of Leds dynamicly
3- What µc use in order to print animations ?

Thanks a lot.

 

[Mike K8LH]

easy68k matrix program

Hi Dal'.

What's the size of your matrix? Is it 8 x 40? Are you representing display data in an array, for example DIM Display(8 ,5 ) {8 rows, 5 bytes/40 bits}?

My display subsystems use a display buffer (array). MAIN manipulates the array and the interrupt driver paints data in the array to the display hardware. MAIN contains subroutines to manipulate the array. These can be routines to shift column data in all eight rows to the left one bit (scroll from right to left), or to the right one bit (scroll from left to right), or to copy entire 40 bit/5 byte rows up or down one row (scroll up or scroll down). You also need code to fill the empty bit or row position after the shift operation.

Clear as mud? Can you write a simple loop to shift the display array below one bit to the left? Display(0,0) bit 7 is the top left LED in the matrix.

 

[blueroomelectronics]

dim attiny2313 2x16

Question:
1- What to do if we have to design a such device but with 140x14 Led.
2- What about If we wanna change the luminosity (or color) of Leds dynamicly
3- What µc use in order to print animations ?

Thanks a lot.

1. with 14 rows you'll need to run the LEDs at a higher than normal current 40ma to 50ma each (times 140)

2. you'll have to refresh the rows very very quickly, then you vary the on time per refresh to dim or brighten each LED to mix the colors. As an example if each LED has 4 levels (0=black, 3=full bright) and an RGB LED you'll get 64 colors 4x4x4

3. whatever you like, it's decent programming skills that are required.

PS if you want 140x14 color LEDs that's the same as 140x14x3 standard LEDs as far as driving them goes. You'll need a hefty power supply to drive them.

 

[Mike K8LH]

attiny13 5x7

Dal'

I should point out that the previous example is crude at best. Higher performance display subsystems might include a display buffer which is much larger than the display hardware. The display driver paints the display hardware using a 'window' into the display buffer which can be changed after each full display refresh interval to perform the scroll operations without the messy bit shift or row copy routines. You can also prepare future display data "off screen" so to speak by painting bits into the array outside of the current display 'window' then simply tell the driver to switch its 'window' focus to that area when you're ready...

 

[leisryan]

moving message display using 8051

For those guys out there wanna build their own message display!!! the schematics are in eagle format!!!

 

[OBIALOR]

led display scrolling easy68k

is this the same as the previous one?

Added after 3 minutes:

the forum is getting interesting again and we need more practical moving sign projects base on at89s52 with ps/2 keyboard to enter text.

Added after 22 minutes:

look at this .

 

[Mike K8LH]

lc7932 dot matrix pic

Question:
1- What to do if we have to design a such device but with 140x14 Led.
2- What about If we wanna change the luminosity (or color) of Leds dynamicly
3- What µc use in order to print animations ?

Thanks a lot.

A 140x14 matrix could be challenging.

If you want to change the color of the entire display rather than individual LEDs then I think I'd use a microcontroller with three PWM channels (like a PIC 16F767 or 16F777) driving the Output Enable lines on the Red, Green, and Blue driver IC sets. This would provide thousands of colors as well as complete fade-to-black brightness control using only a few lines of code (to change the R/G/B PWM duty cycle values).

Mike

 

[MAXPAYNE]

easy68k display ic number

please someone donate me to download 'moving_message.zip' (18MB) in page 11...

Regards

 

[MAXPAYNE]

to display ic number on easy68k

please someone donate me 20 points!

 

[vikky]

project moving msg display

Dear all,
Can anyone help me out.i want the asm code
to interface max6953 and PIC 16f877.it will be better
if you could help me out in interfacing more than two max6953.
Thank u for your help.

 

[drbizzarow]

how can project moving message display.

chk microchip site it wil help i guess

 

[MAXPAYNE]

lc7932 diy

Also searh in this thread... There is a post by ali raza with max6952. I saw before....

 

[vikky]

massage display softare

Thanks 4 ur reply.
drbizzarow....i want to know how to configure max6953 and interface it using I2C.I want to know how to coordinate both of them.
Thanks Maxpayne...the problem is 6952 works with spi and 6953 works with I2C.any way i will go through the previous postings.

 

[nima_khani]

moving message display tutorial

yes i build once and workds good