InterruptMask.h

00001 //***************************************************************************//
00002 /* InterruptMask Library */
00003 /* Napoleon Leoni, February 18,2014*/
00004 /* This class enables masking a GPIO interrupt from a specific MBED pin*/
00005 // Note to get the actual pin number in the LPC of an mbed pin in P0
00006 // simply do pN-P0_0, for example p12-P0_0=17, that is pin 12 in the mbed
00007 // corresponds to Port[0].17 or bit 17 of port 0.
00008 //***************************************************************************//
00009 //* Example usage */
00010 //* >#include "InterruptMask.h"
00011 //* >InterruptIn upPressed(p15);
00012 //* >InterruptMask maskUpButtonInt(p15); //Interrupt mask object allows easy access to 
00013 //* >                                    //mask/unmask interrupts from a GPIO source
00014 //* >void ISRup(void){
00015 //*>    myled1=!myled1;
00016 //*>}
00017 //*>int main() {
00018 //*>    upPressed.rise(&ISRup);
00019 //*>    //downPressed.rise(&ISRdown);
00020 //*>    bool disableInterrupt=false;
00021 //*>    int counter=0,tdelay=10;
00022 //*>    
00023 //*>    while (1) {
00024 //*>        //This section of code periodically (every 10 seconds) masks the specified GPIO interrupt
00025 //*>        //showing how to both mask it and unmask it as well as how to clear pending interrupts
00026 //*>        counter++;
00027 //*>        if(counter>=tdelay){
00028 //*>            disableInterrupt=!disableInterrupt;
00029 //*>            if(disableInterrupt) maskUpButtonInt.maskIntR() ;   //mask interrupt
00030 //*>            if(!disableInterrupt){
00031 //*>                 maskUpButtonInt.ClrInt();       //clear any pending interrupt before unmasking
00032 //*>                 maskUpButtonInt.unMaskIntR();   //unmask interrupt 
00033 //*>            }
00034 //*>            counter=0;
00035 //*>        }
00036 //*>    }
00037 //*>}
00038 
00039 //
00040 //                  TESTS RUN                                               //
00041 // I print to the LCD three important LPC1768 registers: 
00042 // ISER0..Interrupt set Enable register(address 0xE000E100), 
00043 // contents of ISER0 are accesible via: *(NVIC->ISER)
00044 //
00045 // IntEnR..GPIO interrupt enable on rising, shows which pins are attached to EINT3 
00046 // on their rising edge (these are only for mbed pins mapped to LPC pins on Port 0)
00047 // its contents are available using th macro LPC_GPIOINT->IO0IntEnR
00048 // IntEnF..GPIO interrupt enable on falling, shows which pins are attached to EINT3 
00049 // on their falling edge (these are only for mbed pins mapped to LPC pins on Port 0)
00050 // its contents are available using th macro LPC_GPIOINT->IO0IntEnF
00051 //
00052 // The test program periodically masks/unmasks (every 10 seconds) a specified interrupt
00053 // from a GPIO pin, 
00054 // 
00055 //***********************************************************************************
00056 //   TEST DESCRIPTION                 Resulting Register Values                     ANALYSYS
00057 // 1 ISR attached to rise             ISER0       0x0020 0010                       Works as expected when p15 interrupt on rise edge
00058 //   edge of p15(toggle LED1)         IO0IntEnR   0x0082 0000 (when p15 unmasked)   is masked the proper bit appears masked in IO0IntEnR
00059 //   and p12(toggle LED2)             IO0IntEnR   0x0002 0000 (when p15 masked)     and the up action of the joystick does not toggle the LED
00060 //                                                                                  while the down motion continues to work. Once the interrupt
00061 //                                                                                  from p15 is unmasked the up joysstick action works again.
00062 //   TEST DESCRIPTION                                           STATUS
00063 // 2 check mask functionality for all                           PASS
00064 //   GPIO pins attached to joystick , both
00065 //   for rise and fall attached interrupts
00066 //
00067 // 3 When interrupt is cleared (ClrInt() )                      PASS
00068 //   before unmasking there should be no pending 
00069 //   interrupts
00070 //   
00071 //***********************************************************************************
00072 
00073 #include "mbed.h"
00074 
00075 #ifndef INTERRUPTMASK
00076 #define INTERRUPTMASK
00077 
00078 class InterruptMask{
00079     
00080 public:
00081 
00082 private:
00083     int mPin;
00084     int mask;
00085     int unmask;
00086     volatile unsigned int* IOIntEnF; // pointer to register with fall enable interrupt for 
00087                                      // appropriate LPC port depending on the GPIO pin
00088     volatile unsigned int* IOIntEnR;// pointer to register with rise enable interrupt for 
00089                                      // appropriate LPC port depending on the GPIO pin
00090     volatile unsigned int* IOIntClr; //pointer to register to clear interrupt for 
00091                                      // appropriate LPC port depending on the GPIO pin                                
00092 public:
00093     //default constructor required, should not be use will yield error
00094     InterruptMask();
00095     //Constructor to be used, initialize with any valid mbed pin (p5 thru p30 except pins 19-20)
00096     //you will need one InterruptMask for every pin you want ot have control over.
00097     InterruptMask(PinName GPIOpin);
00098     
00099     //This method will mask (disable) any rising edge interrupts of the specified pin
00100     void maskIntR(void);
00101     
00102     //This method will mask (disable) any faling edge interrupts of the specified pin
00103     void maskIntF(void);
00104 
00105     //This method will unmask (enable) any rising edge interrupts of the specified pin
00106     void unMaskIntR(void);
00107 
00108     //This method will unmask (enable) any falling edge interrupts of the specified pin
00109     void unMaskIntF(void);
00110       
00111     //This method will clear any pending interrupts of the specified pin
00112     void ClrInt(void);
00113 
00114 };
00115 
00116 #endif