15 replies to this topic

[Fuginator]

Ahhhhhh..... Can someone lend me a hand before I go nuts?

I am trying to setup two 74HC595 chips to control 16 LED's - and am using the wiring here:
http://arduino.cc/en/Tutorial/ShiftOut
(I hooked up the reset pin 10 to ground it out for clearing, as seen in code)

I am trying to run this using my code, posted below.

Here are two video's of my results, almost on.



(LED1 to the left, then up towards right)

Any kind words / advise on how to fix this up?

Thanks,

Andrew

public class Program
    {
        static OutputPort led = new OutputPort(Pins.ONBOARD_LED, false);
        static OutputPort led0 = new OutputPort(Pins.GPIO_PIN_D0, false);
        static OutputPort SRreset = new OutputPort(Pins.GPIO_PIN_D1, false);

        static Cpu.Pin Data = Pins.GPIO_PIN_D11;
        static Cpu.Pin Clock = Pins.GPIO_PIN_D12;
        static Cpu.Pin Latch = Pins.GPIO_PIN_D8;

        public static void Main()
        {
            // Reset registars (pin 10 on 595)
            SRreset.Write(false);
            SRreset.Write(true);

            display(new bool[] { true, true, true, true, true, true, false, false, true, true, true, true, true, true, false, false });
            Thread.Sleep(1000);
            display(new bool[] { false, false, true, true, true, true, true, true, false, false, true, true, true, true, true, true });
            Thread.Sleep(1000);
            display(new bool[] { false, false, true, true, false, false, true, true, false, false, true, true, false, false, true, true });


            for (int i = 0; i < 16; i++) {
                bool[] tmp = new bool[] { false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false };
                tmp[i] = true;
                display(tmp);
                Thread.Sleep(1000);
            }



            Thread.Sleep(1000); //keep debug window up for a sec.
        }

        private static void display(bool[] vars) {
            // ouput data from array of bool values
            // Outputs
            OutputPort LatchO = new OutputPort(Latch, false);
            OutputPort ClockO = new OutputPort(Clock, false);
            OutputPort DataO = new OutputPort(Data, false);

            for (int i = 0; i < vars.Length; i++)
            {
                // pulse / data
                Debug.Print("Working with: " + i + " set to: " + vars[i]);
                DataO.Write(vars[i]);
                ClockO.Write(true);
                ClockO.Write(false);
                DataO.Write(false);
                //Pz();
                /*if (i % 8 == 0) {
                    // Send the data pulsed to output?
                    Debug.Print("Latch");
                    LatchO.Write(true);
                    LatchO.Write(false);
                    //next chip from here?
                }*/
            }
            LatchO.Write(true);
            LatchO.Write(false);

            LatchO.Dispose();
            ClockO.Dispose();
            DataO.Dispose();
        }

        private static void Pz(){
            // pause w\ some hardware feedback that things are happening
            led.Write(true);
            Thread.Sleep(1);
            led.Write(false);
        }
    }

[Fuginator]

The problem can be seen with just these lines, in the above code (can replace the for loop)...

It should light up the 'true' LED's, but skips 8 and goes to 9, that is on the other IC.

Something wrong with my display function? (also below)

            Thread.Sleep(1000);
            display(new bool[] { false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false });
            Thread.Sleep(1000);
            display(new bool[] { false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false });
            Thread.Sleep(1000);
            display(new bool[] { false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false });

Display function

        private static void display(bool[] vars) {
            // ouput data from array of bool values
            // Outputs
            OutputPort LatchO = new OutputPort(Latch, false);
            OutputPort ClockO = new OutputPort(Clock, false);
            OutputPort DataO = new OutputPort(Data, false);

            // Reset registars (pin 10 on 595)
            SRreset.Write(false);
            SRreset.Write(true);

            for (int i = 0; i < vars.Length; i++)
            {
                // pulse / data
                Debug.Print("Working with: " + i + " set to: " + vars[i]);
                DataO.Write(vars[i]);
                ClockO.Write(true);
                
                DataO.Write(false);
                ClockO.Write(false);
                Pz();
            }
            //latch data
            LatchO.Write(true);
            LatchO.Write(false);

            LatchO.Dispose();
            ClockO.Dispose();
            DataO.Dispose();
        }

[Fuginator]

Okay, I have a good feeling that someone else has used two or more 74HC595 chips w\ their netduino - would they like to share code or wiring? Please?

[AlfredBr]

I've done this (i.e. several '595's) with both the ezExpander and 'from scratch' on a breadboard. Are you more interested in the code or the circuit? I can post the code tonight, but it may take a few days to transcribe the circuit to something that is postable... In the meantime, have you read this? http://forums.netdui...ch__1#entry6593

[Fuginator]

I think code is my issue here - I used code from the post you linked, still a no-go, so I'm going to re-wire now. And by no-go, here were the results:

[Fuginator]

and just the first 595 wireup - should be all off / on cycle.... I would like to see the code you used, may save my sanity. Thanks, Andrew Edit, Added video

[Fuginator]

Wow - I'll check my wiring 4 times before posting, seeing that 3 times was one time too little for things to work. Now works w\ code from other thread, thanks! I would still be interested in your code however. Andrew.

[AlfredBr]

Glad you got it working. I'll post my code tonight. Getting these to work in series is mostly in the circuit. The code does not change when using two '595's, I just pass a 16-bit value.

[Nk54.fr]

Your code is so nice ! It works perfecty with 8 leds. I'm waiting for my 4 shift register OUT (shit ! i've bought some but for input not output lol (i'll make a keyboard so ... ^^) I'll take a picture of mine for you (i've made something very beautifull with the wires hahaha) Now i need to make it work with SPI. It didn't perfecty until now ... Have you already try ? Thank a lot by the way

[Stefan]

Now i need to make it work with SPI. It didn't perfecty until now ... Have you already try ?

Thank a lot by the way

Funny, never seen this thread, but I made a library (including schematics) with those IC's over SPI.
See http://forums.netdui...h-the-netduino/ for more details.

[Nk54.fr]

*can't delete message :/*

[Nk54.fr]

Haha i've already download your code. I've a question, should i use the same pin on my netduino in order to use spi ? I'm using pin 1, 2 ,3 static Cpu.Pin Data = Pins.GPIO_PIN_D2; static Cpu.Pin Clock = Pins.GPIO_PIN_D3; static Cpu.Pin Latch = Pins.GPIO_PIN_D1; your code is very good. But i've not understand everything. Outputportshift Multispi ic...595 ic...595chain I'm not getting everything. I'll try tomorow or in 2 days to make it work with it. That's not so much complex but i'm a noob with netduino stuff. Thanks

[Stefan]

Nope. Managed SPI on Netduino is only possible on pins 11 to 13. See also http://sandbox.netduino.com/SPI.ashx
It's the only managed SPI bus the Netduino has. You could connect the IC's like this schematic:


You could discard the left part if it's only for 595's

[Nk54.fr]

THank you so much for your fast answer ! I was using pin 1 2 3. That could be a reason why it doesn't work ... ^^ I'm going to have a deeper look to your code right now. I'll give you feedback. Good night Stefan and thank for helping ! Netduino got a little community. But a very nice one

[Nk54.fr]

After a first reading, i find that your link is very helpfull ! To understand spi and your code too

[Nk54.fr]

It's working well ! I'm looking to start from scratch to understand and know how it works. I get an idea. But still a bit complicated for me