NbAnalogIn.h

00001 #include "mbed.h"
00002 #include "pinmap.h"
00003 
00004 #ifndef NBANALOGIN_H
00005 #define NBANALOGIN_H
00006 
00007 #define ADC_BUF_SIZE 100
00008 #define ADC_CHANNELS 8
00009 
00010 /** Library for non blocking ADC operation
00011   */
00012   
00013 class NbAnalogIn{
00014 public:
00015 
00016     
00017     /**
00018     * Create a NbAnalogIn object, sets up ADC
00019     *
00020     * @param pin AnalogIn pin to connect to
00021     */
00022     NbAnalogIn( PinName pin );
00023     
00024     /**
00025     * Set interrupt options
00026     *
00027     * @param irqfunc - callback function executed at the end of interrupts
00028     * @param priority - set interrupt priority level. -1 (default) leaves them unchanged
00029     */
00030     void setInterrupt(void (*irqfunc)() = 0, int prio = -1);
00031     
00032     /**
00033     * does a single blocking read and returns a 12 bit output
00034     */
00035     int readBl();
00036     
00037     /**
00038     * starts a conversion and sets the interrupt to fire when ADC is finished
00039     * the result will be put into the internal buffer
00040     *
00041     * @param wait - If true, wait for current adc conversion to finish, 
00042     *               if false (default), stop the current conversion replace it
00043     */
00044     void triggerConv(bool wait = false);    
00045     
00046     /**
00047     * checks if the buffer has new results that can be read
00048     */
00049     bool readable();
00050     
00051     /**
00052     * returns the next value from the buffer
00053     */
00054     int read();
00055     
00056     /** An operator shorthand for read()
00057     */
00058     operator int() {
00059         return read();
00060     }
00061     
00062         
00063 private:
00064     
00065     int buffer[ADC_BUF_SIZE];
00066     int write_pos;      // next position to be written to
00067     int read_pos;       // next position to be read from
00068     
00069     static volatile bool converting;
00070     
00071     uint8_t channel;    // channel of current object (ADC0-7)
00072     void handler( int adc_result );
00073     
00074     static void irq();
00075     static NbAnalogIn* handlers[ADC_CHANNELS]; 
00076     
00077     // custom interrupt handler which, if set, is called after the internal
00078     // interrupt handling
00079     void (* cirq)(); 
00080     
00081 };
00082 
00083 
00084 #endif