Diff: qeihw.cpp

Revision:

0:20a27391f6dc

Child:

2:53f8ae2cf502

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/qeihw.cpp	Sat Dec 11 01:34:35 2010 +0000
@@ -0,0 +1,580 @@
+ /* mbed Library - QEI driver for LP1768 hardware
+ * Copyright (c) 2010, hball
+ * released under MIT license http://mbed.org/licence/mit
+ */
+ 
+/***********************************************************************//**
+ * @file        qeihw.cpp
+ * @brief       Driver file for the QEI hardware. Requires connection to
+ *              internal mbed circuit nodes. Adapted from the CMSIS
+ *              driver, lpc17xx_qei.c, v 2.0
+ * @version     0.0
+ * @date        10 Dec 2010
+ * @author      hb
+ **************************************************************************/
+#include "mbed.h"
+#include "qeihw.h"
+
+QEIHW *QEIHW::instance;
+
+/*********************************************************************//**
+ * @brief        Create a QEI object and configure it.
+ * @param _dirinv Direction invert. When = 1, complements the QEICONF register DIR bit
+ * @param _sigmode Signal mode. When = 0, PhA and PhB are quadrature inputs. When = 1, PhA is direction and PhB is clock
+ * @param _capmode Capture mode. When = 0, count PhA edges only (2X mode). Whe = 1, count PhB edges also (4X mode).
+ * @param _invinx Invert index. When = 1, inverts the sense of the index signal
+ * @return        None
+ **********************************************************************/
+QEIHW::QEIHW(uint32_t _dirinv, uint32_t _sigmode, uint32_t _capmode, uint32_t _invinx)
+{
+    /* Set up clock and power for QEI module */
+    LPC_SC->PCONP |= PCONP_QEI_ENABLE;
+
+    /* The clock for theQEI module is set to FCCLK  */
+    LPC_SC->PCLKSEL1 = LPC_SC->PCLKSEL1 & ~(3UL<<0) | ((PCLKSEL_CCLK_DIV_1 & 3)<<0); 
+
+    /* Assign the pins. They are hard-coded, not user-selected. The index
+     * pin is assigned, even though it is not easily accessed on the mbed.
+     * As it may be unconnected, it is given a pull-up resistor to minimize
+     * power drain.
+     */
+    // MCI0 (PhA)
+    LPC_PINCON->PINSEL3 = (LPC_PINCON->PINSEL3 & PINSEL3_MCI0_MASK) | PINSEL3_MCI0 ;
+    LPC_PINCON->PINMODE3 = (LPC_PINCON->PINMODE3 & PINMODE3_MCI0_MASK) | PINMODE3_MCI0;
+
+    // MCI1 (PhB)
+    LPC_PINCON->PINSEL3 = (LPC_PINCON->PINSEL3 & PINSEL3_MCI1_MASK) | PINSEL3_MCI1 ;
+    LPC_PINCON->PINMODE3 = (LPC_PINCON->PINMODE3 & PINMODE3_MCI1_MASK) | PINMODE3_MCI1;
+
+    // MCI2 (Index)
+    LPC_PINCON->PINSEL3 = (LPC_PINCON->PINSEL3 & PINSEL3_MCI2_MASK) | PINSEL3_MCI2 ;
+    LPC_PINCON->PINMODE3 = (LPC_PINCON->PINMODE3 & PINMODE3_MCI2_MASK) | PINMODE3_MCI2;
+    
+    // Initialize all remaining values in QEI peripheral
+    LPC_QEI->QEICON = QEI_CON_RESP | QEI_CON_RESV | QEI_CON_RESI;
+    LPC_QEI->QEIMAXPOS = 0xFFFFFFFF;                          // Default value
+    LPC_QEI->CMPOS0 = 0x00;
+    LPC_QEI->CMPOS1 = 0x00;
+    LPC_QEI->CMPOS2 = 0x00;
+    LPC_QEI->INXCMP = 0x00;
+    LPC_QEI->QEILOAD = 0x00;
+    LPC_QEI->VELCOMP = 0x00;
+    LPC_QEI->FILTER = 200000;       // Default for mechanical switches.
+
+    // Set QEI configuration value corresponding to the call parameters
+    LPC_QEI->QEICONF = (
+        ((_dirinv << 0) & 1) | \
+        ((_sigmode << 1) & 2) | \
+        ((_capmode << 2) & 4) | \
+        ((_invinx <<3) & 8) );
+       
+    // Mask all int sources   
+    LPC_QEI->QEIIEC = QEI_IECLR_BITMASK;    // Set the "clear" bits for all sources in the IE clear register              
+
+    // Clear any pending ints    
+    LPC_QEI->QEICLR = QEI_INTCLR_BITMASK;   // Set the "clear" bits for for all sources in the Interrupt clear register             
+    
+    /* preemption = 1, sub-priority = 1 */
+    NVIC_SetPriority(QEI_IRQn, ((0x01<<3)|0x01));
+
+    //* Attach IRQ
+    instance = this;
+    NVIC_SetVector(QEI_IRQn, (uint32_t)&_Qeiisr);
+
+    /* Enable interrupt for QEI  */
+    NVIC_EnableIRQ(QEI_IRQn);                       
+  
+}
+
+/*********************************************************************//**
+ * @brief        Resets value for each type of QEI value, such as velocity,
+ *                 counter, position, etc..
+ * @param[in]    ulResetType        QEI Reset Type, should be one of the following:
+ *                                 - QEI_RESET_POS: Reset Position Counter
+ *                                 - QEI_RESET_POSOnIDX: Reset Position Counter on Index signal
+ *                                 - QEI_RESET_VEL: Reset Velocity
+ *                                 - QEI_RESET_IDX: Reset Index Counter
+ * @return        None
+ **********************************************************************/
+void QEIHW::Reset(uint32_t ulResetType)
+{
+    LPC_QEI->QEICON = ulResetType;
+}
+
+/*********************************************************************//**
+ * @brief        De-initializes the QEI peripheral registers to their
+ *                  default reset values.
+ *
+ * @return         None
+ **********************************************************************/
+void QEIHW::DeInit()
+{
+    /* Turn off clock and power for QEI module */
+    LPC_SC->PCONP &= PCONP_QEI_DISABLE;
+
+    /* Return pins to their default assignment (PINSEL = 0, PINMODE = PULLDOWN) */
+    // MCI0 (PhA) -> LED-2 (p1.20)
+    LPC_PINCON->PINSEL3 &= PINSEL3_MCI0_MASK;
+    LPC_PINCON->PINMODE3 = (LPC_PINCON->PINMODE3 & PINMODE3_MCI0_MASK) | PINMODE3_GPIO1p20;
+
+    // MCI1 (PhB) -> LED-4 (p1.23)
+    LPC_PINCON->PINSEL3 &= PINSEL3_MCI1_MASK;
+    LPC_PINCON->PINMODE3 = (LPC_PINCON->PINMODE3 & PINMODE3_MCI1_MASK) | PINMODE3_GPIO1p23;
+
+    // MCI2 (Index) -> p1.24
+    LPC_PINCON->PINSEL3 &= PINSEL3_MCI2_MASK;
+    LPC_PINCON->PINMODE3 = (LPC_PINCON->PINMODE3 & PINMODE3_MCI2_MASK) | PINMODE3_GPIO1p24;
+}
+
+/*********************************************************************//**
+ * @brief        Report direction (QEISTAT bit DIR)
+ *                             
+ * @return       State of the DIR bit (SET or RESET)
+ **********************************************************************/
+FlagStatus QEIHW::Direction()
+{
+    return ((LPC_QEI->QEISTAT & QEI_STATUS_DIR) ? SET : RESET);
+}
+
+/*********************************************************************//**
+ * @brief        Get current position value in QEI peripheral
+ * 
+ * @return        Current position value of QEI peripheral
+ **********************************************************************/
+uint32_t QEIHW::GetPosition()
+{
+    return (LPC_QEI->QEIPOS);
+}
+
+/*********************************************************************//**
+ * @brief        Set max position value for QEI peripheral
+ *
+ * @param[in]    ulMaxPos    Max position value to set
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetMaxPosition(uint32_t ulMaxPos)
+{
+    LPC_QEI->QEIMAXPOS = ulMaxPos;
+}
+
+/*********************************************************************//**
+ * @brief        Set position compare value for QEI peripheral
+ * @param[in]    QEIx        QEI peripheral, should be LPC_QEI
+ * @param[in]    bPosCompCh    Compare Position channel, should be:
+ *                             - QEI_COMPPOS_CH_0: QEI compare position channel 0
+ *                             - QEI_COMPPOS_CH_1: QEI compare position channel 1
+ *                             - QEI_COMPPOS_CH_2: QEI compare position channel 2
+ * @param[in]    ulPosComp    Compare Position value to set
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetPositionComp( uint8_t bPosCompCh, uint32_t ulPosComp)
+{
+    uint32_t *tmp;
+
+    tmp = (uint32_t *) (&(LPC_QEI->CMPOS0) + bPosCompCh * 4);
+    *tmp = ulPosComp;
+}
+
+/*********************************************************************//**
+ * @brief        Get current index counter of QEI peripheral
+ *
+ * @return        Current value of QEI index counter
+ **********************************************************************/
+uint32_t QEIHW::GetIndex()
+{
+    return (LPC_QEI->INXCNT);
+}
+
+/*********************************************************************//**
+ * @brief        Set value for index compare in QEI peripheral
+ * @param[in]    ulIndexComp        Compare Index Value to set
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetIndexComp( uint32_t ulIndexComp)
+{
+    LPC_QEI->INXCMP = ulIndexComp;
+}
+
+/*********************************************************************//**
+ * @brief        Set Velocity timer reload value
+ *
+ * @param[in]    ulReloadValue    Velocity timer reload count
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetVelocityTimerReload( uint32_t ulReloadValue)
+{   
+         LPC_QEI->QEILOAD = ulReloadValue;
+}
+
+/*********************************************************************//**
+ * @brief        Set Velocity timer reload value in microseconds
+ *
+ * @param[in]    ulReloadValue    Velocity timer reload count
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetVelocityTimerReload_us( uint32_t ulReloadValue)
+{
+    int div;
+
+    //Work out CCLK
+    uint32_t m = (LPC_SC->PLL0CFG & 0xFFFF) + 1;
+    uint32_t n = (LPC_SC->PLL0CFG >> 16) + 1;
+    uint32_t cclkdiv = LPC_SC->CCLKCFG + 1;
+    uint32_t Fcco = (2 * m * XTAL_FREQ) / n;
+    uint32_t cclk = Fcco / cclkdiv;
+    
+
+    
+//    div = CLKPWR_GetPCLKSEL(ClkType);
+    div = LPC_SC->PCLKSEL1 & PCLKSEL1_PCLK_QEI_MASK;
+    switch (div)
+    {
+    case 0:
+        div = 4;
+        break;
+
+    case 1:
+        div = 1;
+        break;
+
+    case 2:
+        div = 2;
+        break;
+
+    case 3:
+        div = 8;
+        break;
+    }
+    LPC_QEI->QEILOAD = cclk;
+}
+
+/*********************************************************************//**
+ * @brief        Get current timer counter in QEI peripheral
+ * 
+ * @return        Current timer counter in QEI peripheral
+ **********************************************************************/
+uint32_t QEIHW::GetTimer()
+{
+    return (LPC_QEI->QEITIME);
+}
+
+/*********************************************************************//**
+ * @brief        Get current velocity pulse counter in current time period
+ * 
+ * @return        Current velocity pulse counter value
+ **********************************************************************/
+uint32_t QEIHW::GetVelocity()
+{
+    return (LPC_QEI->QEIVEL);
+}
+
+/*********************************************************************//**
+ * @brief        Get the most recently captured velocity of the QEI. When
+ *                 the Velocity timer in QEI is over-flow, the current velocity
+ *                 value will be loaded into Velocity Capture register.
+ * 
+ * @return        The most recently measured velocity value
+ **********************************************************************/
+uint32_t QEIHW::GetVelocityCap()
+{
+    return (LPC_QEI->QEICAP);
+}
+
+/*********************************************************************//**
+ * @brief        Set Velocity Compare value for QEI peripheral
+ *
+ * @param[in]    ulVelComp        Compare Velocity value to set
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetVelocityComp( uint32_t ulVelComp)
+{
+    LPC_QEI->VELCOMP = ulVelComp;
+}
+
+/*********************************************************************//**
+ * @brief        Set value of sampling count for the digital filter in
+ *                 QEI peripheral
+ * 
+ * @param[in]    ulSamplingPulse    Value of sampling count to set
+ * @return        None
+ **********************************************************************/
+void QEIHW::SetDigiFilter( uint32_t ulSamplingPulse)
+{
+    LPC_QEI->FILTER = ulSamplingPulse;
+}
+
+/*********************************************************************//**
+ * @brief        Check whether if specified interrupt flag status in QEI
+ *                 peripheral is set or not
+ * 
+ * @param[in]    ulIntType        Interrupt Flag Status type, should be:
+                                - QEI_INTFLAG_INX_Int: index pulse was detected interrupt
+                                - QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
+                                - QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
+                                - QEI_INTFLAG_DIR_Int: Change of direction interrupt
+                                - QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
+                                - QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
+                                - QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_REV_Int: Index compare value is equal to the current
+                                                        index count interrupt
+                                - QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
+                                - QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
+                                - QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt
+ * @return        New State of specified interrupt flag status (SET or RESET)
+ **********************************************************************/
+FlagStatus QEIHW::GetIntStatus( uint32_t ulIntType)
+{
+    return((LPC_QEI->QEIINTSTAT & ulIntType) ? SET : RESET);
+}
+
+/*********************************************************************//**
+ * @brief        Enable/Disable specified interrupt in QEI peripheral
+ * 
+ * @param[in]    ulIntType        Interrupt Flag Status type, should be:
+ *                                - QEI_INTFLAG_INX_Int: index pulse was detected interrupt
+ *                                - QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
+ *                                - QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
+ *                                - QEI_INTFLAG_DIR_Int: Change of direction interrupt
+ *                                - QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
+ *                                - QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
+ *                                - QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_REV_Int: Index compare value is equal to the current
+ *                                                        index count interrupt
+ *                                - QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
+ *                                - QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
+ *                                - QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt
+ * @param[in]    NewState        New function state, should be:
+ *                                - DISABLE
+ *                                - ENABLE
+ * @return        None
+ **********************************************************************/
+void QEIHW::IntCmd( uint32_t ulIntType, FunctionalState NewState)
+{
+    if (NewState == ENABLE) {
+        LPC_QEI->QEIIES = ulIntType;
+    } else {
+        LPC_QEI->QEIIEC = ulIntType;
+    }
+}
+
+/*********************************************************************//**
+ * @brief       Assert specified interrupt in QEI peripheral
+ * 
+ * @param[in]    ulIntType        Interrupt Flag Status type, should be:
+                                - QEI_INTFLAG_INX_Int: index pulse was detected interrupt
+                                - QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
+                                - QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
+                                - QEI_INTFLAG_DIR_Int: Change of direction interrupt
+                                - QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
+                                - QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
+                                - QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_REV_Int: Index compare value is equal to the current
+                                                        index count interrupt
+                                - QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
+                                - QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
+                                - QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt
+ * @return        None
+ **********************************************************************/
+void QEIHW::IntSet( uint32_t ulIntType)
+{
+    LPC_QEI->QEISET = ulIntType;
+}
+
+/*********************************************************************//**
+ * @brief       De-assert specified interrupt (pending) in QEI peripheral
+ * 
+ * @param[in]    ulIntType        Interrupt Flag Status type, should be:
+                                - QEI_INTFLAG_INX_Int: index pulse was detected interrupt
+                                - QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
+                                - QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
+                                - QEI_INTFLAG_DIR_Int: Change of direction interrupt
+                                - QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
+                                - QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
+                                - QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the
+                                                        current position interrupt
+                                - QEI_INTFLAG_REV_Int: Index compare value is equal to the current
+                                                        index count interrupt
+                                - QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
+                                - QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
+                                - QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt
+ * @return        None
+ **********************************************************************/
+void QEIHW::IntClear( uint32_t ulIntType)
+{
+    LPC_QEI->QEICLR = ulIntType;
+}
+
+/*********************************************************************//**
+ * @brief        Calculates the actual velocity in RPM passed via velocity
+ *                 capture value and Pulse Per Revolution (of the encoder) value
+ *                 parameter input.
+ * 
+ * @param[in]    ulVelCapValue    Velocity capture input value that can
+ *                                 be got from QEI_GetVelocityCap() function
+ * @param[in]    ulPPR            Pulse per round of encoder
+ * @return        The actual value of velocity in RPM (Revolutions per minute)
+ **********************************************************************/
+uint32_t QEIHW::CalculateRPM( uint32_t ulVelCapValue, uint32_t ulPPR)
+{
+    uint64_t rpm, Load, edges;
+    int div;
+    
+    // Get current Clock rate for timer input
+    //Work out CCLK
+    uint32_t m = (LPC_SC->PLL0CFG & 0xFFFF) + 1;
+    uint32_t n = (LPC_SC->PLL0CFG >> 16) + 1;
+    uint32_t cclkdiv = LPC_SC->CCLKCFG + 1;
+    uint32_t Fcco = (2 * m * XTAL_FREQ) / n;
+    uint32_t cclk = Fcco / cclkdiv;
+    
+//    div = CLKPWR_GetPCLKSEL(ClkType);
+    div = LPC_SC->PCLKSEL1 & PCLKSEL1_PCLK_QEI_MASK;
+    switch (div)
+    {
+    case 0:
+        div = 4;
+        break;
+
+    case 1:
+        div = 1;
+        break;
+
+    case 2:
+        div = 2;
+        break;
+
+    case 3:
+        div = 8;
+        break;
+    }
+    cclk /= div;
+    
+    // Get Timer load value (velocity capture period)
+    Load  = (uint64_t)(LPC_QEI->QEILOAD + 1);
+    // Get Edge
+    edges = (uint64_t)((LPC_QEI->QEICONF & QEI_CONF_CAPMODE) ? 4 : 2);
+    // Calculate RPM
+    rpm = ((( uint64_t)cclk * ulVelCapValue * 60) / (Load * ulPPR * edges));
+
+    return (uint32_t)(rpm);
+}
+
+/*********************************************************************//**
+ * @brief        Append interrupt handler for specific QEI interrupt source
+ * 
+ * @param[in]    ulISRType        Interrupt Flag Status type, should be:
+ *                                - QEI_INTFLAG_INX_Int: index pulse was detected interrupt
+ *                                - QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
+ *                                - QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
+ *                                - QEI_INTFLAG_DIR_Int: Change of direction interrupt
+ *                                - QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
+ *                                - QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
+ *                                - QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_REV_Int: Index compare value is equal to the current
+ *                                                        index count interrupt
+ *                                - QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
+ *                                - QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
+ *                                - QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt
+ *                                 
+ * @return       none
+ **********************************************************************/
+void QEIHW::AppendISR(uint32_t ulISRType, void(*fptr)(void)) {
+    int i;
+    
+    for(i = 0; i < 13; i++) {
+        if( ulISRType == (1UL << i) ) {
+            _qei_isr[i] = fptr;
+            break;
+        }
+    }
+    return;
+}
+
+/*********************************************************************//**
+ * @brief        Unappend interrupt handler for specific QEI interrupt source
+ * 
+ * @param[in]    ulISRType        Interrupt Flag Status type, should be:
+ *                                - QEI_INTFLAG_INX_Int: index pulse was detected interrupt
+ *                                - QEI_INTFLAG_TIM_Int: Velocity timer over flow interrupt
+ *                                - QEI_INTFLAG_VELC_Int: Capture velocity is less than compare interrupt
+ *                                - QEI_INTFLAG_DIR_Int: Change of direction interrupt
+ *                                - QEI_INTFLAG_ERR_Int: An encoder phase error interrupt
+ *                                - QEI_INTFLAG_ENCLK_Int: An encoder clock pulse was detected interrupt
+ *                                - QEI_INTFLAG_POS0_Int: position 0 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_POS1_Int: position 1 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_POS2_Int: position 2 compare value is equal to the
+ *                                                        current position interrupt
+ *                                - QEI_INTFLAG_REV_Int: Index compare value is equal to the current
+ *                                                        index count interrupt
+ *                                - QEI_INTFLAG_POS0REV_Int: Combined position 0 and revolution count interrupt
+ *                                - QEI_INTFLAG_POS1REV_Int: Combined position 1 and revolution count interrupt
+ *                                - QEI_INTFLAG_POS2REV_Int: Combined position 2 and revolution count interrupt
+ *                                 
+ * @return       none
+ **********************************************************************/
+void QEIHW::UnAppendISR(uint32_t ulISRType) {
+    int i;
+    
+    for(i = 0; i < 13; i++) {
+        if( ulISRType == (1UL << i) ) {
+            _qei_isr[i] = NULL;
+            break;
+        }
+    }
+    return;
+}
+
+
+void QEIHW::_Qeiisr(void)
+{
+    instance->Qeiisr();
+}
+
+/*********************************************************************//**
+ * @brief        QEI interrupt service dispatcher. 
+ * 
+ * @param[in]    none
+ *                                 
+ * @return       none
+ **********************************************************************/
+void QEIHW::Qeiisr(void)  
+{
+    int32_t i;
+
+    //User defined interrupt handlers. Check all possible sources, dispatch to corresponding non-null service routines.
+    for(i = 0; i < 13; i++) {
+        if(LPC_QEI->QEIINTSTAT & ((uint32_t)(1<<i)) ) {
+            if (_qei_isr[i] != NULL) {
+                _qei_isr[i]();
+            }
+        }
+    }
+    return;
+}
+