Hello,
I’m using the FEZ Cobra board with the EMX module
I’m writing my own touchscreen driver, for this I need IO72 / IO73 and AD0 / AD1.
But when i use the code:
static OutputPort xMin = new OutputPort((Cpu.Pin)FEZ_Pin.Digital...;
i cannot find IO72 or IO73??
This is also for the AD0 and AD1, how can i solve this??
Thanks already
just do this
static OutputPort xMin = new OutputPort((Cpu.Pin)72, ....);
You can also include this library:
GHIElectronics.NETMF.Hardware.EMX.dll
ans use this:
GHIElectronics.NETMF.Hardware.EMX.Pin.IO72
AD0 == IO8
AD1 == IO5
I once started to write a touchscreen driver but didn’t finish it, it might get you started:
using System;
using System.Threading;
using GHIElectronics.NETMF.Hardware;
using Microsoft.SPOT;
using Microsoft.SPOT.Hardware;
using Math = System.Math;
namespace CobraTouchTest
{
public delegate void TouchEvent(int x, int y);
public class TouchDriver : IDisposable
{
#region Consts
private const int RES_PLATE_X = 602;
private const int RES_PLATE_Y = 377;
private const int ADC_BITS = 10;
private const int MIN_Z_VALUE = 40;
private const int MAX_PRESSURE_RES = 1000;
private const int IDLE_DELAY_MS = 40;
private const int TOUCH_DELAY_MS = 20;
#endregion
#region Declarations
private int resPlateX;
private int resPlateY;
private int adcBits;
private Thread thread;
private ManualResetEvent terminate = new ManualResetEvent(false);
private bool rawMode = false;
#endregion
#region Construction / destruction
public TouchDriver()
: this(RES_PLATE_X, RES_PLATE_Y, ADC_BITS)
{
}
public TouchDriver(int resPlateX, int resPlateY, int maxAdc)
{
this.resPlateX = resPlateX;
this.resPlateY = resPlateY;
this.adcBits = maxAdc;
thread = new Thread(new ThreadStart(TouchThread));
thread.Priority = ThreadPriority.AboveNormal;
thread.Start();
}
~TouchDriver()
{
Dispose();
}
public void Dispose()
{
if (thread != null)
{
terminate.Set();
thread.Join();
thread = null;
}
}
#endregion
#region Thread proc
private void TouchThread()
{
int x = 0, y = 0, z, pressure;
int prevX = -1, prevY = -1;
int maxAdc = (1 << adcBits) - 1;
while (!terminate.WaitOne(IDLE_DELAY_MS, false))
{
while ((z = ReadZ()) > MIN_Z_VALUE)
{
x = ReadX();
y = ReadY();
// calculate touch resistance
pressure = (x * resPlateX) / z - ((x * resPlateX) - ((maxAdc - y) * RES_PLATE_Y)) / maxAdc;
Debug.Print("X=" + x.ToString() + " Y=" + y.ToString() + " P=" + pressure.ToString());
if (pressure < MAX_PRESSURE_RES)
{
if (prevX < 0)
OnPenDown(x, y);
else
{
if ((Math.Abs(x - prevX) > 3) || (Math.Abs(y - prevY) > 3))
OnPenMove(x, y);
}
prevX = x;
prevY = y;
}
if (terminate.WaitOne(TOUCH_DELAY_MS, false))
break;
}
if (prevX >= 0)
{
OnPenUp(prevX, prevY);
prevX = prevY = -1;
}
}
}
#endregion
#region Private methods
private int ReadX()
{
using (AnalogIn yu = new AnalogIn((AnalogIn.Pin)1))
{
using (OutputPort xl = new OutputPort((Cpu.Pin)8, true))
using (OutputPort xr = new OutputPort((Cpu.Pin)72, false))
{
return yu.Read();
}
}
}
private int ReadY()
{
using (AnalogIn xl = new AnalogIn((AnalogIn.Pin)0))
{
using (OutputPort yu = new OutputPort((Cpu.Pin)5, true))
using (OutputPort yd = new OutputPort((Cpu.Pin)73, false))
{
return xl.Read();
}
}
}
private int ReadZ()
{
using (AnalogIn xl = new AnalogIn((AnalogIn.Pin)0))
{
using (OutputPort xr = new OutputPort((Cpu.Pin)72, false))
using (OutputPort yu = new OutputPort((Cpu.Pin)73, true))
{
return xl.Read();
}
}
}
#endregion
#region Event
public event TouchEvent PenDown;
private void OnPenDown(int x, int y)
{
Debug.Print("OnPenDown");
if (PenDown != null)
PenDown(x, y);
}
public event TouchEvent PenUp;
private void OnPenUp(int x, int y)
{
Debug.Print("OnPenUp");
if (PenUp != null)
PenUp(x, y);
}
public event TouchEvent PenMove;
private void OnPenMove(int x, int y)
{
Debug.Print("OnPenMove");
if (PenMove != null)
PenMove(x, y);
}
#endregion
#region Properties
public bool RawMode
{
get { return rawMode; }
set { rawMode = value; }
}
#endregion
}
}
Note that I removed the resistors from the 4.3inch panel that are in parrallel with the touchpanel signals, to get the z axis working.
Thanks for the reply, I will try this!
Hello,
I’m busy with you anwser, but when I use the analog input a get an error:
An unhandled exception of type ‘System.InvalidOperationException’ occurred in GHIElectronics.NETMF.Hardware.dll
The code:
//Read x value for touchscreen
static private int TouchScreenReadX()
{
AnalogIn x = new AnalogIn((AnalogIn.Pin)1);
x.SetLinearScale(0, 1023);
int _x = x.Read();
return _x;
}
What is wrong?!
I was forget to tell you that i use TristatePort to switch betwoon output/inpt
The problem is you can only assign a pin once. So you’re stuck with that enormous overhead of creating and disposing objects, unless you use rlp.
Hello,
Thanks to Wouter for piece of driver code. I have modified it adopted to my EMX custom board which uses different pins for touch panel. But I have not found any example or explantions on the net to hook this driver to touch system. Is it possible?
Glide library has an easy way to take user input. An example is provided
Thanks Gus, I will try…