A PIC C Code Wizard

// Timers.cpp : implementation file
//

#include "stdafx.h"
#include "PICCPC.h"
#include "Timers.h"
#include <math.h>

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CTimers property page

IMPLEMENT_DYNCREATE(CTimers, CPropertyPage)

CTimers::CTimers() : CPropertyPage(CTimers::IDD)
{
	//{{AFX_DATA_INIT(CTimers)
	m_iWDTTimeout = -1;
	m_dwT0Freq = 32768;
	m_dDesiredOverflow = 0.0;
	//}}AFX_DATA_INIT
}

CTimers::~CTimers()
{
}

void CTimers::DoDataExchange(CDataExchange* pDX)
{
	CPropertyPage::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CTimers)
	DDX_Control(pDX, IDC_T0_RESOLUTION, m_cT0Resolution);
	DDX_CBIndex(pDX, IDC_WDTTIMEOUTS, m_iWDTTimeout);
	DDX_Text(pDX, IDC_T0CKI_FREQ, m_dwT0Freq);
	DDV_MinMaxDWord(pDX, m_dwT0Freq, 1, 1000000000);
	DDX_Text(pDX, IDC_T0_COUNTER, m_dDesiredOverflow);
	DDX_Control(pDX, IDC_T0CKI_OVERFLOW, m_sInfo);
	//}}AFX_DATA_MAP
}


BEGIN_MESSAGE_MAP(CTimers, CPropertyPage)
	//{{AFX_MSG_MAP(CTimers)
	ON_BN_CLICKED(IDC_T0CS1, OnT0cs1)
	ON_BN_CLICKED(IDC_T0CS2, OnT0cs2)
	ON_BN_CLICKED(IDC_T0CS3, OnT0cs3)
	ON_EN_CHANGE(IDC_T0CKI_FREQ, OnChangeT0ckiFreq)
	ON_BN_CLICKED(IDC_T0_USEPRESCALER, OnT0Useprescaler)
	ON_CBN_SELCHANGE(IDC_T0_RESOLUTION, OnSelchangeT0Resolution)
	ON_CBN_EDITCHANGE(IDC_WDTTIMEOUTS, OnEditchangeWdttimeouts)
	ON_EN_CHANGE(IDC_T0_COUNTER, OnChangeT0Counter)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

CTimers::UpdateT0CKIFreq( BOOL bEnable ) {
	CString s;
	s.Format( "%u", PICInfo.dwT0Freq );
	SetDlgItemText( IDC_T0CKI_FREQ, s );
	GetDlgItem(IDC_T0CKI_FREQ)->EnableWindow( bEnable );
}

CTimers::UpdateT0ResolutionList() {
	CString s;
	int k = 1;
	double fv;
	if ( PICInfo.sfr.OPTION&0x20 ) {
		fv = GetT0ExtResolution()*1e3;
	}
	else {
		fv = m_dT0MCUResolution*1e3;
	}
	m_cT0Resolution.ResetContent();
	if ( !(PICInfo.sfr.OPTION&0x08) ) { //prescaler is asigned to TMR0
		((CComboBox*)GetDlgItem(IDC_WDTTIMEOUTS))->SetCurSel( 0 );
		((CComboBox*)GetDlgItem(IDC_WDTTIMEOUTS))->EnableWindow( FALSE );
		for ( int i=1;i<9;i++ ) {
			fv *= (k*2);
			s.Format( "%G", fv );
			m_cT0Resolution.AddString( s );
		}
		m_cT0Resolution.SetCurSel( PICInfo.sfr.OPTION&0x07 );
		OnSelchangeT0Resolution();
	}
	else { //prescaler is asigned to WDT
		((CComboBox*)GetDlgItem(IDC_WDTTIMEOUTS))->EnableWindow();
		s.Format( "%G", fv );
		m_cT0Resolution.AddString( s );
		m_cT0Resolution.SetCurSel( 0 );
		((CComboBox*)GetDlgItem(IDC_WDTTIMEOUTS))->SetCurSel( PICInfo.sfr.OPTION&0x07 );
	}
}

double CTimers::GetT0ExtResolution() {
	if ( !UpdateData() )
		return 0.0;
	return 1.0/m_dwT0Freq;
}

/////////////////////////////////////////////////////////////////////////////
// CTimers message handlers

CTimers::UpdateOPTION( BYTE mask, BYTE value ) {
	PICInfo.sfr.OPTION &= mask;
	PICInfo.sfr.OPTION |= value;
}

BOOL CTimers::OnKillActive() 
{
	if ( !CPropertyPage::OnKillActive() )
		return FALSE;

	if ( PICInfo.sfr.OPTION&0x08 ) {
		UpdateOPTION( 0xF8, ((CComboBox*)GetDlgItem(IDC_WDTTIMEOUTS))->GetCurSel() );
	}
	else {
		UpdateOPTION( 0xF8, ((CComboBox*)GetDlgItem(IDC_T0_RESOLUTION))->GetCurSel() );
	}
	PICInfo.sfr.INTCON &= 0xDF;
	PICInfo.sfr.INTCON |= (IsDlgButtonChecked(IDC_T0_INTEN)<<5);
	return TRUE;
}

BOOL CTimers::OnSetActive() 
{
	// update timer0
	m_dT0MCUResolution = PICInfo.dInstructionTime;
	CheckDlgButton( IDC_T0_INTEN, PICInfo.sfr.INTCON&0x20 );
	CheckDlgButton( IDC_T0_USEPRESCALER, !(PICInfo.sfr.OPTION&0x08) );
	switch( PICInfo.sfr.OPTION&0x30 ) {
	case 0x30:
		CheckRadioButton( IDC_T0CS1, IDC_T0CS3, IDC_T0CS2 );
		OnT0cs2();
		break;
	case 0x20:
		CheckRadioButton( IDC_T0CS1, IDC_T0CS3, IDC_T0CS3 );
		OnT0cs3();
		break;
	default:
		CheckRadioButton( IDC_T0CS1, IDC_T0CS3, IDC_T0CS1 );
		OnT0cs1();
	}

	return CPropertyPage::OnSetActive();
}

void CTimers::OnT0cs1() 
{
	PICInfo.sfr.OPTION &= 0xDF;
	PICInfo.dwT0Freq = PICInfo.dwOSCFrequency>>2;
	UpdateT0CKIFreq( FALSE );
	UpdateT0ResolutionList();
}

void CTimers::OnT0cs2() 
{
	PICInfo.sfr.OPTION |= 0x30;
	PICInfo.dwT0Freq = m_dwT0Freq;
	UpdateT0CKIFreq( TRUE );
	UpdateT0ResolutionList();
}

void CTimers::OnT0cs3() 
{
	PICInfo.sfr.OPTION |= 0x20;
	PICInfo.sfr.OPTION &= 0xEF;
	PICInfo.dwT0Freq = m_dwT0Freq;
	UpdateT0CKIFreq( TRUE );
	UpdateT0ResolutionList();
}

void CTimers::OnChangeT0ckiFreq() 
{
	if ( !UpdateData() )
		return;
	PICInfo.dwT0Freq = m_dwT0Freq;
	UpdateT0ResolutionList();
	UpdateT0Interrupt();
}

void CTimers::OnT0Useprescaler() 
{
	if ( IsDlgButtonChecked(IDC_T0_USEPRESCALER) ) {
		PICInfo.sfr.OPTION &= 0xF7;
	}
	else {
		PICInfo.sfr.OPTION |= 0x08;
	}
	UpdateT0ResolutionList();
}

void CTimers::OnSelchangeT0Resolution() 
{
	UpdateT0Interrupt();
	UpdateOPTION( 0xF8, ((CComboBox*)GetDlgItem(IDC_T0_RESOLUTION))->GetCurSel() );
}

void CTimers::OnEditchangeWdttimeouts() 
{
	UpdateOPTION( 0xF8, ((CComboBox*)GetDlgItem(IDC_WDTTIMEOUTS))->GetCurSel() );
}

void CTimers::OnChangeT0Counter() 
{
	if ( !UpdateData() )
		return;
	UpdateT0Interrupt();
	CheckDlgButton( IDC_T0_INTEN, 1 );
}

void CTimers::UpdateT0Interrupt() {
	if ( !UpdateData() )
		return;
	if ( m_dDesiredOverflow < PICInfo.dInstructionTime*50000.0 && m_dDesiredOverflow != 0.0 ) {
		m_dDesiredOverflow = PICInfo.dInstructionTime*50000.0;
		UpdateData( FALSE );
	}
	PICInfo.dwT0Offset = 0;
	PICInfo.dwT0Counter = 0;
	CString s;
	GetDlgItemText( IDC_T0_RESOLUTION, s );
	double fv = atof( s );
	DWORD tmp = (DWORD)(m_dDesiredOverflow/fv);
	m_dDesiredOverflow = tmp*fv;
	for ( unsigned int i=MAXBYTE+1;i>0;i-- ) {
		double y = fv*i;
		double f = fmod( m_dDesiredOverflow, y );
		double x = fabs(f-y);
		if ( f == 0.0 || x<1e-13 ) {
			PICInfo.dwT0Offset = MAXBYTE - i + 1;
			PICInfo.dwT0Counter = (DWORD)(m_dDesiredOverflow/(fv*i));
			if ( !PICInfo.dwT0Counter )
				PICInfo.dwT0Counter = 1;
			s.Format( "Interrupt every/total:\t%fms, %fms\n"
				"Timer offset:\t\t%u\n"
				"Timer counter:\t\t%u",
				i*fv,
				((256-PICInfo.dwT0Offset)*fv)*PICInfo.dwT0Counter,
				PICInfo.dwT0Offset,
				PICInfo.dwT0Counter );
			m_sInfo.SetWindowText( s );
			break;
		}
	}
}