C / C++ / MFC

Re: C CODE FOR RUNNING TWO SENSORS FOR BI-DIRECTIONAL COUNTING

3-Nov-12 7:34

I AM A LITTLE BIT EXPERIENCED WITH C PROGRAMMING AND PICS BUT AM WONDERING IF ANYONE OUT THERE CAN HELP WITH THE CODE TO RUN A PIC16F8777A OR AN ARDUINO WITH TWO IR SENSORS S1 AND S2 TO PERFORM BIDIRECTIONAL COUNTING IN AND OUT. IN THE FIRST SEQUENCE BREAKING FIRST S1 AND THEN S2 WILL TELL THE MICROCONTROLLER TO INCREMENT THE COUNTER WHILE BREAKING THE SECOND SEQUENCE, FIRST S2 AND THEN S1 WOULD TELL THE MICROCONTROLLER TO DECREMENT THE COUNTER.THE MICROONTROLLER SHOULD ALSO STORE AND TIMESTAMP THE COUNTS AND BE ABLE TO PASS THE TIMESTAMPED DATA TO A REMOTE COMPUTER VIA BLUETOOTH OR WIFI.
ANY HELP WILL BE GREATLY APPRECIATED.

THANK YOU.

Tr@v3-Nov-12 11:15

Tr@v

3-Nov-12 11:15

Are the sensors tied to a GPIO line or do you have to talk to them using IIC or SPI? Need a little more info about the sensors before I could offer more assistance. I'm familiar with ARM (mostly Freescale and Atmel stuff) and I'd say that the sensors that I work with are generally tied to a GPIO pin. In that case you just need to read the GPIO pin status or tie it to an interrupt and read them in your app. The logic handling should be simple enough, if S1 is tripped before S2 then increment your counter and log the event to whatever permanent storage you are using, and decrement if you see the sensors in the opposite order. Not having much experience with PIC parts I don't know the exact registers you would need to check for the GPIO status though.

Re: C CODE FOR RUNNING TWO SENSORS FOR BI-DIRECTIONAL COUNTING

STEVE10K5-Nov-12 7:57

Re: C CODE FOR RUNNING TWO SENSORS FOR BI-DIRECTIONAL COUNTING

5-Nov-12 7:57

I am tieing a pair of infrared sensors S1 and S2 onto GPIO lines(digital I/O) of any microcontroller that is easy to program in C as I am new to this.I am looking into ARDUINO UNO(ATmega328 MCU),ARDUINO MEGA(ATmega1280) or a PIC16F877A.I will use the Microcontroller to read the interrupts from the sensors as they change on being broken in the sequence mentioned before.
My main problem is the real coding in C of the logic onto my app.
Can you help with the code?? I wish to have the following functionality:

1) Read interrupts from sensors
2)Increment or decrement counter depending on sequence they are broken
3) timestamp the count and enable storing
4) Pass timestapmed data onto a remote host computer via bluetooth or Wifi.
Do you suggest any parcticular Microcontroller for this application?

Thank you very much.

Tr@v7-Nov-12 7:47

Tr@v

7-Nov-12 7:47

Try something like the following for your interrupt handlers. Depending on the micro you select, how to install these will be different. I would stay away from PIC parts, I personally don't like them. The Atmega family of MPU should be better to work with in my opinion, although my personal favorite these days is the Freescale Kinetis family of MPU's. You can get demo boards in the form of expandable towers from Freescale.

[EDIT] You may also want to handle rollover for the counter variable if you expect to have counts high enough for this to happen.

C++

#define S1  (1 << 0)
#define S2  (1 << 1)

unsigned char sensorFlags = 0;
int counter = 0;

/* interrupt handler for S1 */
void s1_isr(void)
{
 if(sensorFlags & S2)
 {
    /* Exiting, decrement counter */
    --counter;
    /* clear S2 flag */
    sensorFlags &= ~S2;
    /* Get timestamp, store it, transmit to remote host
      this will depend a lot on your hardware */
 }
 else if(sensorFlags & S1)
 {
    /* ERROR same sensor tripped twice, handle as necessary */
 }
 else
 {
    /* Entering, set S1 flag */
    sensorFlags |= S1;
 }

  /* clear interrupt flag if necessary */
}

/*interrupt handler for S2 */
void s2_isr(void)
{
 if(sensorFlags & S1)
 {
    /* Entering, increment counter */
    ++counter;
    /* clear S1 flag */
    sensorFlags &= ~S1;
    /* Get timestamp, store it, transmit to remote host
      this will depend a lot on your hardware */
 }
 else if(sensorFlags & S2)
 {
    /* ERROR same sensor tripped twice, handle as necessary */
 }
 else
 {
    /* Exiting, set S2 flag */
    sensorFlags |= S2;
 }

 /* clear interrupt flag if necessary */
}

modified 7-Nov-12 14:05pm.

Re: C CODE FOR RUNNING TWO SENSORS FOR BI-DIRECTIONAL COUNTING

STEVE10K8-Nov-12 3:41

Re: C CODE FOR RUNNING TWO SENSORS FOR BI-DIRECTIONAL COUNTING

8-Nov-12 3:41

Hi Tr@V,

This is great mate and I appreciate your help so much.
I am thinking of going for either ARDUINO MEGA/ARDUINO 2560
which have ATMEL 1280 and ATMEL 2560 chips respecetively.I will probably have to connect a bluetooth or wifi shield and a SD card for storing.Am not much aware of Freescale Kinetis family of MPU's you suggested but will check them out.

Any chance I can get your email address or phone number incase i hit hard rocks?I may need your help.I'll also let you know how far have gone.

Thanks.

STEVE10K3-Dec-12 2:49

C++ question. Please help me out

3-Dec-12 2:49

I have made some good progress with my ISR and am serial printing the count on the serial monitor, now what I want to achieve is to call the count to be displayed on my 3 digit seven seg cc display or rather let the ISR trigger the counts whenever the sensors flag depending on their sequence. I have the code to count from 0-999 back to 0 so my problem is how to combine with the ISR. Any help is much appreciated.

Much thanks.

Member 88567522-Nov-12 9:06

Member 8856752

2-Nov-12 9:06

Kindly gurus,
Assist me in the below questions. I am new in C++ and even don't know where to start. Please somebody help me out

Write a program using functions that prompts for the input of social security numbers upto a maximum of 10. Store the social security numbers in a two dimensional array of characters. Ask if the array of social security numbers is to be sorted in ascending or descending order, then call a bubble sort function that you write to sort the array. The program should print the unsorted list first, sort the list, then print the sorted list. The bubble sort algorithm is as follows:

A. Start with the first two array elements.
B. Compare the elements and exchange them if the
compare function indicates they should be swapped.
C. Bump up one element and repeat step B.
D. Continue until the end of the array is reached.
E. Repeat steps B -> D decreasing the upperlimit on
the array by one for each iteration of the loop.
In other words, stop one element short of the
previous iteration in the main loop.
F. End the sort if:
1. No exchanges occur during an iteration or
2. The upper limit for the loop reaches one.

Re: C++ question. Please help me out

jeron12-Nov-12 9:18

jeron1

2-Nov-12 9:18

Member 8856752 wrote:
Assist me in the below questions.

You haven't asked any questions.

Member 8856752 wrote:
Please somebody help me out

See here[^].

Re: C++ question. Please help me out

Richard MacCutchan2-Nov-12 10:23

Richard MacCutchan

2-Nov-12 10:23

Member 8856752 wrote:
Write a program

That looks very like an instruction telling you to do some assignment for school or college. So, if someone here wrote it for you, would you still expect to submit it as your own work?

It would be better if you made an effort to write at least part of it, and come back here with more specific issues when you get stuck.

One of these days I'm going to think of a really clever signature.

Re: C++ question. Please help me out

Amarnath S3-Nov-12 20:49

Amarnath S

3-Nov-12 20:49

Since you've already written the pseudo-code, it should be straightforward to convert it to working code.

Anyway, you can always do:
- an internet search for "bubble sort implementation in C++"
- then compare the steps there with the ones you've listed
- modify the code there to suit your requirements
- run and test it
- and, most important, make sure that you understand, and are able to explain each line of your code.

how to return value after user input

Member 21198442-Nov-12 5:11

2-Nov-12 5:11

Hi All,

i need to return input value after press enter. how to make it. need little help.
the main think here that i have to make function that return value after press Enter.

here is link of project file.

https://skydrive.live.com/redir?resid=78B222720843DE16!116&authkey=!AAjKOKZHSd-q9lI

i have a dialog box with 2 EditBox (m_TxInput and m_TxOutPut) and 2 Button for (GetString and GetNumber)

i made class CMyTextBox for m_TxInput . here is code below. i have 2 function GetString and GetNumber in CMyTextBox Class. i am calling these function on button down in dlg.

C++

/////////////////////////////////////////////////////////////////////////////
// CMyTextBox window

class CMyTextBox : public CEdit
{
// Construction
public:
	CMyTextBox();

// Attributes
public:

// Operations
public:

	bool InFlag; // After Press Enter InFlag = true;
	CString RetVal; // store return value

// Overrides
	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CMyTextBox)
	//}}AFX_VIRTUAL

// Implementation
public:
	CString GetString();
	double GetNumber();
	virtual ~CMyTextBox();

	// Generated message map functions
protected:
	//{{AFX_MSG(CMyTextBox)
	afx_msg void OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags);
	//}}AFX_MSG

	DECLARE_MESSAGE_MAP()
};


// CPP file======================================================

// CMyTextBox message handlers

void CMyTextBox::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
    // TODO: Add your message handler code here and/or call default
    if (nFlags == 28) // Enter press
        GetWindowText(RetVal);
    CEdit::OnKeyDown(nChar, nRepCnt, nFlags);
}

double CMyTextBox::GetNumber()
{
// how to get return here after press enter by user
    if (InFlag == true)
        return atof(RetVal);
    return 0;
}

CString CMyTextBox::GetString()
{
// how to get return here after press enter by user
    if (InFlag == true)
        return RetVal;
    return "";
}

Thanks

Amrit

modified 2-Nov-12 14:29pm.

Richard MacCutchan2-Nov-12 6:25

Richard MacCutchan

2-Nov-12 6:25

This is not the best way to implement a dialog. You should allow the user to fill in the various fields and then capture the data when the OK button is pressed. In general you do not need to check for key down characters, since most CEdit classes offer other methods and events for checking the content, and the CDialog class offers the UpdateData()[^] method to capture all fields.

One of these days I'm going to think of a really clever signature.

Member 21198442-Nov-12 8:16

2-Nov-12 8:16

well, this is what i have to complete task. it is required.

Richard MacCutchan2-Nov-12 10:19

Richard MacCutchan

2-Nov-12 10:19

Fine, you do it any way you want.

One of these days I'm going to think of a really clever signature.

Santhosh G_2-Nov-12 6:34

2-Nov-12 6:34

I felt three problems.
1) InFlag is always false. You have to set it to true from OnKeyDown with Enter key.

C++

if (nFlags == 28) // Enter press
{
InFlag = true;
GetWindowText(RetVal);
}

2) Please ensure you added ON_WM_KEYDOWN() in message map of CMyTextBox class.
3) Normally an Edit control will not get Enter key press, On Enter keypress, focused button click action will be performed.
One option is to change the style of your Edit control to Multi-line. Change MultiLine to true, or enable ES_MULTILINE for the CMyTextBox window style.
Another option is to identify enter keypress from PreTranslateMessage(), if "VK_ENTER" key down is occurred from edit control set your InFlag to true.

Member 21198442-Nov-12 7:51

2-Nov-12 7:51

yes i have add InFlag = true; it is not working.

CString CMyTextBox::GetString()
{
// how to come here after press enter by user that is main thing
    if (InFlag == true)
        return RetVal;
    return "";
}

it is call form dialog class here is code.

void CRetValTestDlg::OnGetString()
{
    m_TxInput.InFlag = false;
    CString s = m_TxInput.GetString();
    m_TxOutput.SetWindowText (s);
}
void CRetValTestDlg::OnGetNumber()
{
    m_TxInput.InFlag = false;
    CString s;
    double d = m_TxInput.GetNumber();
    s.Format ("%d",d);
    m_TxOutput.SetWindowText (s);
}

i would like to upload project file for review. if possible.

Santhosh G_2-Nov-12 15:32

2-Nov-12 15:32

Few comments.
1) First statement of CRetValTestDlg::OnGetString() set InFlag to false. Therefore m_TxInput.GetString() will return "".
Move InFlag = false to CRetValTestDlg::OnGetString(). Accessing a member variable outside of class is not a good.
2) First statement of CRetValTestDlg::OnGetNumber() set InFlag to false. Therefore m_TxInput.GetString() will return 0. Move InFlag = false to CRetValTestDlg::OnGetNumber().
3) modify CMyTextBox::OnKeyDown() like this

if (nFlags == 28) // Enter press
{
    InFlag = true;
    GetWindowText(RetVal);
}

4) Need to identify Enter KeyPress in your EditControl. 3) Normally an Edit control will not get Enter key press, On Enter keypress, focused button click action will be performed.
One option is to change the style of your Edit control to Multi-line. Change MultiLine to true, or enable ES_MULTILINE for the CMyTextBox window style.
Another option is to identify enter keypress from PreTranslateMessage(), if "VK_ENTER" key down is occurred from edit control set your InFlag to true.

Member 21198442-Nov-12 17:19

2-Nov-12 17:19

yes i did as you said.
the functions does not work. because functions does not wait for Enter.

The function call from outer class so that InFlag has to false until press enter but with out press enter function ends. the function is not giving chance to press Enter or type any text to Edit box.

Santhosh G_2-Nov-12 17:26

2-Nov-12 17:26

Which function ?
On every key press, CMyTextBox::OnKeyDown() will call. But Enter will not called. Its reason is "Enter" keypress will consider as Action of currently focused button. please change the MultiLine property of EditBox and check whether enter is recieved in KEyDown

Member 21198442-Nov-12 17:33

2-Nov-12 17:33

keyDown received Enter. that is not a problem. but if you see my code you will find that function does not wait for enter. function are (double CMyTextBox::GetNumber() and CString CMyTextBox::GetString()) they have to wait until press enter. i think the problem is this.

here is link of project file.
https://skydrive.live.com/redir?resid=78B222720843DE16!116&authkey=!AAjKOKZHSd-q9lI

please kindly check test project.

Santhosh G_2-Nov-12 18:01

2-Nov-12 18:01

Please move GetWindowText() to CMyTextBox::GetNumber() and CMyTextBox::GetString(). CMyTextBox::OnKeyDown() will not give text values.

CRetValTestDlg::OnGetString() still calls m_TxInput.InFlag = false; Please remove it.

Member 21198442-Nov-12 18:34

2-Nov-12 18:34

no no. this is not a way what i need. i need to get value after press Enter Key.

Santhosh G_2-Nov-12 18:43

2-Nov-12 18:43

"After press Enter key" I can undestand that you need to get the String and Number values on pressing Enter key.is it right ?

Member 21198442-Nov-12 20:02