Controling a Split flap Display System of 65 modules with Arduino via I2C bus

Robin2: I can't make any sense of the image Sans-titre-1.jpg - what is it intended to convey? What is the thing that is connected to the Arduino?

In Reply #17 you lead me to think that there are only 2 serial cables and one sends data for 40 motors and the other sends data for 25 motors. Is that correct?

Rather than expect me to read lots of links and learn all about something I am never going to use perhaps you could provide a synopsis of each of the links. That way maybe I don't need to look at all of them.

...R

I am sorry for making you confused, i will try to illustrate more informative plan and share it here as soon as possible

johnwasser:
I’m beginning to think that the 5-conductor “serial” cable is a 16-conductor multi-drop ribbon cable. Perhaps the term “serial cable” means something other than what we typically use it for.

It appears to be an Ethernet MAC which makes NO sense at all. I suspect it was used to represent a “12C to unknown interface adapter” of unknown design.

The OP is trying to do reverse engineering while admitting to being “no good at reverse engineering”.

Hi John ,

In fact its a 16-conductor multi-drop ribbon cable connected in series with 5 motor drivers, that same cables is going to motherboard , and from the motherboard you get the 5-conductor “serial” cable

Just concentrate on the serial cable until you know for definite that it cannot be used. If it can be used it will be much the simplest option.

We await the info promised in Reply #20.

...R

Hi , I am so sorry for the delay , i live in algeria (GMT+1) and i just saw your feedbacks, thanks a lot guys, and sorry again !

my goal is to reverse engineer a PCB motor controller of a Split flap display , the split flap works with a synchronous 48 AC motor.

this is what found in this PCB :

FQP50N06 Transistor MOSFET

MOC3020 : 6 Pin DIP Ramdom-Phase Optoisolators Triac Driver Output

4 x MC3302 : Quad voltage comparator

1 x MC1413B : Hight Volatge, Hight Current Darling Transistor Arrays

3x MC14516B : Binary Up/Down Counter

MC14081b : Dual 4-Input AND Gate

2 Photointerrupters ( I have 2 photo interrupters in this circuit, one for the tuning and one for the steps of the synchronous motor )

After 3 days of work i made an initial Control Schematic :

I want to use the original 16-conductor multi-drop ribbon cable ( check the top of PCB please), i want to know what i get from every conductor of the 16 conductors and control the motor using an arduino.

like the example here :

https://www.youtube.com/watch?v=ISs-sn-Swj8

What should i do next ?

Many thanks for your help !

If that was my project I would focus on the wires coming from each display unit. I think you said there are 16 coming from each and they are combined into a single 16 way cable for the microprocessor.

Is my summary correct?

Is there also a 16 way cable coming from the unit with 8 displays - or is it a cable with more wires - if so, how many altogether?

My guess is that some of the wires are used to select which device is used - one for each device perhaps - although the "address" could be multiplexed.

If you can identify a wire that connects to one display and not to any other that would be a good start.

I don't think your diagram is helpful without noting the function of all the pins on the chips so that you can begin to see how the control system works.

In the display unit is there evidence of something that identifies a particular character - so that the microprocessor can know where to start counting?

I would assume that the control system is simple -

  • at startup find the home position by running through the characters until the home character is triggered.
  • to get to a particular character start the motor and count the characters. Stop when the correct character has come around.

...R

To a large extent I feel you are making this a lot more complicated than it needs to be.
From the ‘schematic’ you’ve drawn out, there doesn’t seem to be any significant intelligence on the board.

You’ve already done a lot if the hard work, now redraw your schematic with the usual i/o on the left, supply rails at top and bottom, and driven devices on the right where possible.
You already have your logic Vcc and GND identified from the ic pins - so 20% of your wires will disappear.

When you have a readable schematic, the functionality should become abundantly clear, along with ideas how to stimulate Utah into life.

If possible, try to search out the ic part numbers, which will help understand the logical functionality.

EDIT : The MC3302 seem to be an analog comparator, which is a little unusual in this application, so the circuit is more important than usual to understand what’s going on.

Is it possible the comparators are just used as logic gates that make the system more resilient against variations in signal voltage?

...R

Robin2: Is it possible the comparators are just used as logic gates that make the system more resilent against variations in signal voltage?

...R

Good idea. A meaningful schematic would help figure it out.

Robin2: If that was my project I would focus on the wires coming from each display unit. I think you said there are 16 coming from each and they are combined into a single 16 way cable for the microprocessor.

I would assume that the control system is simple -

  • at startup find the home position by running through the characters until the home character is triggered.
  • to get to a particular character start the motor and count the characters. Stop when the correct character has come around.

...R

Hi Robin this will be my 2nd step, but i order to finish the project , i need to prove to my boss that i can control a single module with an arduino

mehdidib:
Hi Robin this will be my 2nd step, but i order to finish the project , i need to prove to my boss that i can control a single module with an arduino

The stuff I put in bullet points is for a single display module. In fact when I look back at my earlier Reply it was all about a single module.

You need to identify which of the 16 wires are needed for a single module. Maybe it is all of them, but I find that hard to believe - unless some of them (perhaps 4 of them) are used for binary addressing. 4 wires could address 16 modules.

…R

Hello guys,

I made alot of mistakes in my last Draft Schematic, please find in the attached pdf the clean version , I am still tracing the schematic using EAGLE software, I starting thinking that the 2 Binary Up/Down Counters are getting information from the 2 photo interrupters and transmit it to Dual Type D Flip-Flop.

In order to control the motor i need to know what i get as an input and output from every 16 cable, after I make the schematic I will use it to work out what I need to do on the inputs for it to start/stop the motor, and to read out the sensors.

I also found the characteristic of my synchronous motor:

Robin2: The stuff I put in bullet points is for a single display module. In fact when I look back at my earlier Reply it was all about a single module.

You need to identify which of the 16 wires are needed for a single module. Maybe it is all of them, but I find that hard to believe - unless some of them (perhaps 4 of them) are used for binary addressing. 4 wires could address 16 modules.

...R

when you're talk about one module you mean one display ?

Here is what i mean by one display

for now i just want to control the destination module of the display .

please find in the attached pdf the clean version of the draft Schematic Here :

https://drive.google.com/open?id=0B4hGEKcQurgOR2hSX3RVZXhPM185YVpNdWRHT1BSSlRNSVRB

lastchancename: To a large extent I feel you are making this a lot more complicated than it needs to be. From the 'schematic' you've drawn out, there doesn't seem to be any significant intelligence on the board.

You've already done a lot if the hard work, now redraw your schematic with the usual i/o on the left, supply rails at top and bottom, and driven devices on the right where possible. You already have your logic Vcc and GND identified from the ic pins - so 20% of your wires will disappear.

When you have a readable schematic, the functionality should become abundantly clear, along with ideas how to stimulate Utah into life.

If possible, try to search out the ic part numbers, which will help understand the logical functionality.

EDIT : The MC3302 seem to be an analog comparator, which is a little unusual in this application, so the circuit is more important than usual to understand what's going on.

thanks your post was so helpful , I still working on the final schematics , and yeah the MC3302 is an Quad voltage comparator with 4inputs and 4 outputs, please check my new draft and let me know what you think

this is how I want to control a single module with arduino

mehdidib: when you're talk about one module you mean one display ?

I am trying to be as simple as possible. I am talking about the mechanism that displays a single character. If I have understood you correctly you have a unit that has 5 characters and another that has 8 characters.

The image at the bottom of Reply #16 shows the 5 character display - if I understand it correctly. I am referring to one of those 5 characters.

What exactly do you mean when you say "for now i just want to control the destination module of the display" ?

...R

Robin2: I am trying to be as simple as possible. I am talking about the mechanism that displays a single character. If I have understood you correctly you have a unit that has 5 characters and another that has 8 characters.

The image at the bottom of Reply #16 shows the 5 character display - if I understand it correctly. I am referring to one of those 5 characters.

What exactly do you mean when you say "for now i just want to control the destination module of the display" ?

...R

Thats exactly what i wanted to say , one of the 5 character

mehdidib: Thats exactly what i wanted to say , one of the 5 character

Now go back and re-read my Replies with that in mind.

...R

---circular reference! Carve the elephant into pieces, it is too large to manage as one piece!

lastchancename: Carve the elephant into pieces,

That's what I have been trying to encourage :)

And I strongly suspect it is only a wildebeest.

...R