cce1911

I'm seeing some odd behavior for what should be a simple project. Maybe I'm missing something and someone can point out the error of my ways?

What I'm trying to do is capture a sensor input. To test my code I've simulated the sensor with a simple momentary push button. See the schematic attached.

The problem is when I push one button, it triggers the interrupt for the other buttons. Here is my code:

public class Program2        {        static DateTime dtLastPress;        static int intBounceWait = 200;        public static void Main()            {            InterruptPort ipT1 = new InterruptPort(Pins.GPIO_PIN_D0, false, Port.ResistorMode.PullDown, Port.InterruptMode.InterruptEdgeLow);            ipT1.OnInterrupt += T_OnInterruptT1;            InterruptPort ipT2 = new InterruptPort(Pins.GPIO_PIN_D1, false, Port.ResistorMode.PullDown, Port.InterruptMode.InterruptEdgeLow);            ipT2.OnInterrupt += T_OnInterruptT2;            InterruptPort ipT3 = new InterruptPort(Pins.GPIO_PIN_D2, false, Port.ResistorMode.PullDown, Port.InterruptMode.InterruptEdgeLow);            ipT3.OnInterrupt += T_OnInterruptT3;            InterruptPort ipT4 = new InterruptPort(Pins.GPIO_PIN_D3, false, Port.ResistorMode.PullDown, Port.InterruptMode.InterruptEdgeLow);            ipT3.OnInterrupt += T_OnInterruptT4;            Thread.Sleep(Timeout.Infinite);            }        static void T_OnInterruptT1(uint data1, uint data2, DateTime time)            {            if (dtLastPress.AddMilliseconds(intBounceWait) > time)  // prevent bounce                {                Debug.Print("T1 = bounce wait");                return; // prevent bounce                }            dtLastPress = time;            RecordPress(1, time);            }        static void T_OnInterruptT2(uint data1, uint data2, DateTime time)            {            if (dtLastPress.AddMilliseconds(intBounceWait) > time)  // prevent bounce                {                Debug.Print("T2 = bounce wait");                return; // prevent bounce                }            dtLastPress = time;            RecordPress(2, time);            }        static void T_OnInterruptT3(uint data1, uint data2, DateTime time)            {            if (dtLastPress.AddMilliseconds(intBounceWait) > time)  // prevent bounce                {                Debug.Print("T3 = bounce wait");                return; // prevent bounce                }            dtLastPress = time;            RecordPress(3, time);            }        static void T_OnInterruptT4(uint data1, uint data2, DateTime time)            {            if (dtLastPress.AddMilliseconds(intBounceWait) > time)  // prevent bounce                {                Debug.Print("T4 = bounce wait");                return; // prevent bounce                }            dtLastPress = time;            RecordPress(4, time);            }        static void RecordPress(int intTarget, DateTime time)            {            Debug.Print("T" + intTarget.ToString() + " = " + DateTime.Now.ToString("MM/dd/yy H:mm:ss.fff"));            }        }

If I run the code and press the buttons in order (T1, T2, T3, T4) I get the following output:

So I have gotten my shift register to work with my N+2, but the lasers I'm trying to drive require 300mA of current each. So to drive 9 of these, I need almost 3A at 2.5 - 4.5 vdc.  This is way too much for the N+2 and the 74HC595. I've been looking at some transistor arrays, but I'm not sure how to wire them. Can anyone point me to a circuit that uses this 8ch Darlington Sink driver(or something similar)?

Can someone point me to an example of using this breakout board with the Netduino?

https://www.sparkfun.../products/10680

I would like to use the .Net Microframework Toolbox, but it's not obvious to me how to wire it up.

I have a N+2 driving 2 stepper motors with the Sparkfun Easydriver. I have wired up several external buttons

InterruptPort ipT1 = new InterruptPort(Pins.GPIO_PIN_D0, false, Port.ResistorMode.Disabled, Port.InterruptMode.InterruptEdgeLow);ipT1.OnInterrupt += Target_OnInterruptT1;InterruptPort ipT2 = new InterruptPort(Pins.GPIO_PIN_D1, false, Port.ResistorMode.Disabled, Port.InterruptMode.InterruptEdgeLow);ipT2.OnInterrupt += Target_OnInterruptT2;

?

Here are my event handlers

        static void Target_OnInterruptT1(uint data1, uint data2, DateTime time)            {            if (dtLastHit.AddMilliseconds(intBounceWait) > time) return; // prevent bounce            dtLastHit = time;            Debug.Print("Hit T1 = " + DateTime.Now.ToString("MM/dd/yy H:mm:ss.fff"));            }        static void Target_OnInterruptT2(uint data1, uint data2, DateTime time)            {            if (dtLastHit.AddMilliseconds(intBounceWait) > time) return; // prevent bounce            dtLastHit = time;            Debug.Print("Hit T2 = " + DateTime.Now.ToString("MM/dd/yy H:mm:ss.fff"));            }

My problem is that when I press button T1 it randomly executes Target_OnInterruptT2 or Target_OnInterruptT1. No rhyme or reason. The same thing happens if I press button T2.

What is odd is that I've used this same exact board with 5 buttons, in the past, and had no problems. Any idea what is happening? I thought it might be EMI from the Easy driver, but I still get the same behavior even if I disconnect power to the stepper motors.

I'm scratching my head...

In my N+2 app, I log things to a text file for later debugging. I use this code in a function:

using (var filestream = new FileStream(@"SDrunlog.txt",FileMode.Append))                    {                    StreamWriter streamWriter = new StreamWriter(filestream);                    streamWriter.WriteLine(DateTime.Now.ToString("MM/dd/yy H:mm:ss.fff") + ": " + strMsg);                    streamWriter.Close();                    //Debug.Print(DateTime.Now.ToString("MM/dd/yy H:mm:ss.fff") + ": " + strMsg);                    }

When my log file gets over 33k I get a failed allocation error when creating the new streamwriter:

StreamWriter streamWriter = new StreamWriter(filestream);

Any idea on what is causing this and how to avoid it?