DIY Moving Message Display

Re: MMD for "Gujrati" language

Hi Zuisti sir,

I got your point..even i had tried for some my language's font and those are displayed also
but as you had seen that my language needs more size display (like.. 16x16). Because the character's width & height is too big than the English.

So i request to you sir that kindly give me below schematic's code..(even that is also developed by you but code not provided)

Thank you Zuisti sir.

From that i'll get my solution..and i'll post my result here.

Thank you Zuisti sir.

MMD bitmaps

Hi hardik.patel;

As I wrote the (Proton Basic !!) source is almost full with assembly , and it is not public, sorry.
What I can even help you (really do not have time, and also now be traveling for one week): yet attached the bitmap files used in my project.
Study the structure, and make your own characters. Since they are already in binary form, we just have to a text-editor (and lots of time).
Then create your message(s), using the newly defined char-numbers (identifiers) like me in the 'msg_c.inc' and the 'used-fnts.txt' files.

zuisti
PS:
If you are familiar with the PIC18 assembly and have an installed Proton Basic compiler, I can give more help you (but not here in the forum !) after I came back. Sorry, but I have utterly no time to convert the source to C.
Note:
If you think, feel free to use the "Helped me" button ...

Re: MMD bitmaps

Hi Zuisti sir..

Actually i just want a code of 16x16 Led Matrix (work is as same as your old design of 8x8..just display a string on led) not needed other features of Multilang..

in short i just want big display because my language characters need big size than 8x8.
And about font that i will create my self sir..just give me code of 16x16 LED.

Re: MMD bitmaps

Hi zuisti sir,

After referring your so many posts of 5x7 & a latest one of 8x8, i had tried for 16x16 from your design, but i dont get a proper output.
Here i had upload a code & proteous file.

The code i am using is from 8x8 (your design) but i had created a circuit my own.

As i wish to design 16x16 from your concept, but somehow i cant get a proper output.

So kindly sir help to solved it.


Regard & Thanks

Hardik Patel

16x16 MMD

Hi hardik.patel;

The code you are using was written for a 10 x 8x8 matrix, without modification it is unable to control a big 16x16 matrix. Your DSN is also bad, for example how to drive the plus 8 rows (R8..R16)?
Advices:
- use a PIC18,
- use a 4 to 16 decoder to drive the rows,
- use a new big (16x16) character bitmap,
- ... drop me a PM.

However, here is a DSN what I'm using to display large (complex) chars.
Note this is a two-sheet design: the matrix and the proc sheet (right click to choose one)

Read again and carefully my previous post (#702, especially the PS).
zuisti

I have two versions, one STM8, an STM32
I hope to help you

View attachment STM8.pdf

View attachment STM32.pdf

Hi zuisti sir,

As per your big scroll design...i am trying forward,

but i cant understand regarding """RB_4, RB_5, RB_6, RB_7""

where i had to connect it??

hardik.patel said:

i cant understand regarding """RB_4, RB_5, RB_6, RB_7""
where i had to connect it??

Click to expand...

RB_4 is the same as the PORTB.B4 (and so on).
but on a PIC18 it's better to use the LAT register bits eg LATB_4 to avoid 'RMW' (read-modify-write) problems.

Re: moving message display source code

Hello glenjoy can you please help me to codes in c for a moving message on LED DOT MATRIX using PIC16F876A,ULN2803,74LS138,74LS164 and 8*8 LED DOT MATRIX.

When I amke a simulation in proteus I get the good result but the implementation on the baord doesnot work;so I added a ULN2803 for driving the LED DOT MATRIX but in the simulation and in the Codes nothing works,can you please help me??

Re: moving message display source code

@hardik.patel
I had a mistake in my previous post (#708), sorry.
The asked RB_4 ... pins are used for button-reading (via the 'on change interrupt' feature), look at my complete DSNs. Note almost all DSN (using a big, two-line matrix) is a two-sheet design.

@jean12
Some advices/notes:

- Using LS(HC)138 with ULN2803 is a bad pairing because the 138 has active low outputs while the 2803 has active high inputs. Use LS(HC)238 instead. It's the same as the 138 but has active high outputs. Or use 8 additional inverters to drive the 2803 with the 138.

- Using a LM2803 as row-driver (it is enough only for not too long matrices, eg 3 * 8x8) you must have common cathode (row-side) matrices. In this case the columns are active high (common anode) so you do not have to invert the output bits when the bitmap table is also active high (bit 1 = led lit). But the table you are using is the opposite (bit 0 = led lit), so have to invert the bits via software.

- In Proteus the job is simpler, in the matrix properties window you can set (or turn off ) any inversion. In order to create a fast simulation - for example - you can create a matrix that is active low at both side (row and column), and you can omit the row-side drivers (ULNxx). In Proteus (only here!) you can also omit the the column-side current limiting resistors.

- If you are using the row-scanning method, the LS(HC)164 does not a good choice, always use HC595 shiftregs instead, to avoid the flickering. The HC595 has (a very useful) output storage feature, so you do not have to switch off all lines while the new datas are loaded in.

- About your sources:
I'm sorry but I do not use (do not like and not know enough) the CCS compiler. In my works I'm using only the Proton Basic (PDS), the MicroC Pro for PIC, or - often - a pure assembler. The uploaded sources I do not understand really, so I cannot help more.

You will find many examples (working projects) in our forums. I suggest you look at my posts (for example): click on my profile then the 'find latest posts'.

I hope the above helps you (and others too).
zuisti

Re: moving message display source code

Hello Sir Zuisti, the problem I have is that I don't have the 74HCT595 and those 74LS238 (I can't even find them in my country);so what about using cd4017 for controlling ULN2803 (when refering https://embedded-lab.com/blog/?p=2661to this link);with 74HCT164 I don't care about flickering but first I want to see those letters displayed on the matrix;can you help me coding and replace the 74LS138 buy CD4017 in Mikroc?I don't know it very well but I can understand a little bit I am justi learning the MikroC

Last time in this post I have been told to put NOT gate on the output of 74LS138 but also I did not get any good output.

So please help on coding in Mikroc considering the circuits attached;if possible provide some comments.

The pinout connections I used is here https://circuitdesolator.blogspot.com/2010/12/led-dot-matrix-pin-configuration.html;is that right I might?
I used this is (ROW as Anode) on the board that means the pins are connected as follows:

Between ULN2803 and DOT Matrix respectively:
1(Pin 11 of ULN2803) goes to PIN 16 of dot matrix
2(Pin 12 of ULN2803) goes to PIN 15 of dot matrix
3(Pin 13of ULN2803) goes to PIN11 of dot matrix
4(Pin 14 of ULN2803) goes to PIN 6 of dot matrix
5(Pin 15 of ULN2803) goes to PIN 10 of dot matrix
6(Pin 16 of ULN2803) goes to PIN 4 of dot matrix
7(Pin 17 of ULN2803) goes to PIN 3 of dot matrix
8(Pin 18 of ULN2803) goes to PIN 13 of dot matrix

And for 74LS164 and DOT MATRIX I connected the pins as follow:


3 (Pin 3 of 74LS164) goes to PIN 5 of dot matrix
4(Pin 4of 74LS164) goes to PIN 2 of dot matrix
5(Pin 5 of 74LS164) goes to PIN 7 of dot matrix
6(Pin 6 of 74LS164) goes to PIN 1 of dot matrix
10(Pin 10 of 74LS164) goes to PIN 12 of dot matrix
11(Pin 11of 74LS164) goes to PIN 8 of dot matrix
12(Pin 12 of 74LS164) goes to PIN 14 of dot matrix
13(Pin 13 of 74LS164) goes to PIN 9 of dot matrix




It is my first time to use the DOT Matrix can you also tell me with the pinout on the link which one I might use.

Thanks for helping.

MMD using 4017, ULN2803 and HC164

Hi jean12;

I made a project (attached), just as you wished: it uses a PIC16F876A, three 8x8 LED matrices, a 4017 (instead of LS138) with ULN2803, and three HC164 (instead of HC595). There are also a Start-Stop switch (see the DSN).

MikroC and my row-scan algorithm was used, and also my bold characters (look at the picture below).

The source is resizeable (expandable for a longer matrix) with a simple define:
#define MATRICES 3 //number of 8x8 matrices (and 164 shiftregs), now 3.

To avoid 'shadows' and 'ghosts' a little trick is used:
- all matrix rows are switched off while (re)loading the HC164 chain. This is not as simple because of the 4017.

Note this is a Proteus-only project, but it uses COF so you can debug it step-by-step also at source level.
Use it Enjoy!
zuisti

Hello Sir,Zuisti,how may I use normal font of characters not Those Bold ones?

Thanks.

Re: MMD using 4017, ULN2803 and HC164

With the same circuits ,how may I modify the codes for inserting the space between the last word of the sentence and the first when the repeats starts.
For example I implemented the circuits but when I DISPLAY FOR EXAMPLE WELCOME TO MESSAGE MOVING WITH LED DOT MATRIX,the first sentence is well displayed but for the second round the last wordMATRIX is concantenated with DISPLAY"the first word of the sentence";I tried to put space but nothing going on;what can I do for that?

Thanks

Font is not a problem. You can use any font. You can create your own stylish font set.

No just the problem I have is putting the space between the first sentence and the second for repetition.

Thanks

Zip and post the project files. Let me see if I can modify.

I checked Zuisti's file and it works fine. Change the string to the string you want. See attached file. It displays 'Hi Jean".

Thanks. I av been searching for this thread

jean12 said:

... space between the first sentence and the second for repetition

Click to expand...

As I wrote already (also in my source) the trailing spaces work as separator while scrolling:

Your question about the bold chars was answered on your other thread. Simply comment out this define line, so:

Otherwise, please tell me/us how to works the project in reality. For example no any flickering? The brightness is also enough?

zuisti

The Project doesn't have any flickering I will try to post a snapshot I took when it was operating physically.

Thanks for the response.