7X25 Dot Matrix Display Project

[NeoMatrix]

Hello Everyone

i am new to pic and i know little c i am very much interested to build Dot matrix moving message display for 1st i want to build for 5 of 5x7 i have pic1684a, pic16f628 74hc164,74hc595 and uln2003 and uln2803 can anybedy pls help me to do this i need simple schematic and code so that i can understand plsssssssssssssssss

i am searching since 2 weeks finally i registerd in ccs so that i can get help here

can anybedy give me the schematic and code i be so thanful with pic16f628 and the explanation of 74hc595 plssssssss
waiting for reply

plssssssssssssssssssssssssssssssssss

[NeoMatrix]

hello

nobedy is here to help me i am waiting since 3 days come on plssssssssssss

[bfemmel]

NeoMatrix;

It's not that we don't want to help, its just that the scope of what you are asking is fairly large. You want the schematic and the code, what part are you going to do?

But anyway, it's midnight and I have a few spare minutes. What you should be doing is searching the web. I just did and came up with a handfull right away. There are a whole bunch of projects on the web like the one you want to build. Specifically, try the one at http://home.wanadoo.nl/electro1/avr/dotmatrix.htm. His pages load very slowly but print them out and read them as they are very good in explaining everything he did. He does not use a PIC but that is not a problem. You can modify the schematic and code for any processor you want. You shouldn't need anything else to get you going. Come back when you have something built and need to debug some code. At least come back to let us know if you got a good grade.

Good luck;

Bruce

[NeoMatrix]

hello befemmel

if nobedy wants to give the code its ok i just want to explanaiton how can i do that thats it here i have the schematic

http://www.geocities.com/neomatrix80/Embeded/prjschem.jpg

i don't now how 74595 works i jusst need the simple explanations how to send the data to 595 and how to send the characters to the 5x7 i build the circuit of 2 5x7 in bread board i tried alot but not get anything so i am searching atleast can anybedy give me so idea

thanks for ur reply

[bfemmel]

[NeoMatrix]

hello bruce

yes i have the datasheet and i am printing that link which u given to me and i have searched in this forms there is some code but i not understand as u said if i attach 5 of 5x7 then how many rows and cols it will be in 1 i attached 5 of 5x7 so i think its 25 cols and 7 rows so i posted like this i am so confused i mean i am looking for a simple code with explanation i think i will not find its better that i try my self by seein that link u have given to me

i think i have 5 x 7 for understaind purpose i just attached 2 of 5x7 and 2 74hc595

1 little query can u tell me how to send the data for each row its take from bottom to top or top to bottom like say i given 1110001 so it will display from bottom or top
thanks for ur cooperation

[bfemmel]

NeoMatrix;

Since you are so very lost on this simple project I think that what you need to do is to break up the task into small pieces you can digest and understand. Start by building a simple circuit up with one 5x7 and just get it to display a character, any character, on the display. Try getting the hardware to run the display without the PIC in place if you can, you can hard wire the bits to test your wiring, just whatever you need to do to break down the problem into something that can be debugged easily. Then add the PIC and display a character and next work at making the character move, then add 5x7 segments and so on and so forth. You can't start with the entire circuit and code because you wouldn't understand it unless you had your hand in putting it together. Starting small is the way we all do these things.

As for writing data to the 74HC595, remember what it is, a SERIAL to PARALLEL converter. We know we need the parallel lines to address the array so you will need to write the data into it by a serial method, try the SPI or do some bit banging. On a processor with an external 8 bit bus you could also use a parallel in/out device, the 74HC595 just helps keep the pin count down.

Give your self some time to study and digest what you have found so far. Between the link you have and the link I gave you, you should have all the information you need to put this project together. There are a lot of engineering problems to figure out in this, both hardware and software architecture problems. Most of these answers are in the data you have. So break up the task and come back in a few days when you have had some success with the very simplist of circuits using these parts.

Good luck again

Bruce

[NeoMatrix]

hello bfemmel

thanks for the advice i got ur point i think i am going tooo fast with knowing anything if i get the code and schematic may be i can build the circuit but i will not understand the procedure u told is good break in to small pieces and understand little things then only we can do big things i appreciate ur effort to eplaining me by taking ur valuable time as ccs c demo version i can't write the code of pic16f84a and pic16f628 i will start studying MicroC and start from the scratch by doing little and simple projects 1st i will learn c and basic electronics then small code programming of leds and ports then slightly i will go for moving message

once again thanks for the advice i like this

Best luck for me and u

have a nice day

[Guest]

[Matrix4U]

Hello to all

i build the circuit using pic16f877A and 6 of 5x7 30x7 for cols i am connection through porta to 74hc595 and uln2803a and for rows connecting from portb b

pls can any bedy give me simple little code to test my hard and to understand to implement this

thanks alot