c – 类中的易失性变量：“在’volatile’之前预期的nonqualified-id”？

概述我在类ADC中定义了两个静态volatile变量.该类编写为:(裁剪以节省空间) #pragma once#include "../PeriodicProcess/PeriodicProcess.h"#include <stdint.h>#include <stdlib.h>class ADC{private: static inline unsigned char SPI 我在类ADC中定义了两个静态volatile变量.该类编写为:(裁剪以节省空间)

#pragma once#include "../PeriodicProcess/PeriodicProcess.h"#include <stdint.h>#include <stdlib.h>class ADC{private:    static inline unsigned char SPI_transfer(unsigned char data);    voID read(uint32_t tNow);    static const unsigned char adc_cmd[9];    static volatile uint32_t _sum[8];    static volatile uint16_t _count[8];public:    ADC();    voID raw();    voID init(PeriodicProcess * scheduler);    double ch(uint8_t c);    bool available(const uint8_t *channelNumbers);    uint32_t ch6(const uint8_t *channelNumbers,double *result);};

但是编译项目会在第29,29,39行的cpp文件中引发错误. 44：

ADC.cpp到目前为止：

#include "ADC.h"extern "C" {    // AVR libC Includes    #include <inttypes.h>    #include <stdint.h>    #include <avr/interrupt.h>}#include "Arduino.h"const unsigned char ADC::adc_cmd[9] = { 0x87,0xC7,0x97,0xD7,0xA7,0xE7,0xB7,0xF7,0x00 };#define bit_set(p,m)   ((p) |= ( 1<<m))#define bit_clear(p,m) ((p) &= ~(1<<m))// We use Serial Port 2 in SPI Mode#define ADC_DATAOUT     51    // MOSI#define ADC_DATAIN      50    // MISO#define ADC_SPICLOCK    52    // SCK#define ADC_CHIP_SELECT 33    // PC4   9 // PH6  Puerto:0x08 Bit mask : 0x40// DO NOT CHANGE FROM 8!!#define ADC_ACCEL_FILTER_SIZE 8#define TCNT2_781_HZ   (256-80)#define TCNT2_1008_HZ  (256-62)#define TCNT2_1302_HZ  (256-48)unsigned char ADC::SPI_transfer(unsigned char data){    // Put data into buffer,sends the data    UDR2 = data;    // Wait for data to be received    while ( !(UCSR2A & (1 << RXC2)) );    // Get and return received data from buffer    return UDR2;}ADC::ADC(){    //Do nothing}voID ADC::read(uint32_t tNow){    uint8_t ch;    bit_clear(PORTC,4);                            // Enable Chip Select (PIN PC4)    ADC_SPI_transfer(adc_cmd[0]);                       // Command to read the first channel    for (ch = 0; ch < 8; ch++) {        uint16_t v;        v = ADC_SPI_transfer(0) << 8;            // Read first byte        v |= ADC_SPI_transfer(adc_cmd[ch + 1]);  // Read second byte and send next command        if (v & 0x8007) {            // this is a 12-bit ADC,shifted by 3 bits.            // if we get other bits set then the value is            // bogus and should be ignored            continue;        }        if (++_count[ch] == 0) {            // overflow ... shouldn't happen too often            // unless we're just not using the            // channel. Notice that we overflow the count            // to 1 here,not zero,as otherwise the            // reader below Could get a division by zero            _sum[ch] = 0;            _count[ch] = 1;        }        _sum[ch] += (v >> 3);    }    bit_set(PORTC,4);                  // disable Chip Select (PIN PC4)}voID ADC::init(AP_PeriodicProcess * scheduler){    pinMode(ADC_CHIP_SELECT,OUTPUT);    digitalWrite(ADC_CHIP_SELECT,HIGH);  // disable device (Chip select is active low)    // Setup Serial Port2 in SPI mode    UBRR2 = 0;    DDRH |= (1 << PH2); // SPI clock XCK2 (PH2) as output. This enable SPI Master mode    // Set MSPI mode of operation and SPI data mode 0.    UCSR2C = (1 << UMSEL21) | (1 << UMSEL20); // |(0 << UCPHA2) | (0 << UCPol2);    // Enable receiver and transmitter.    UCSR2B = (1 << RXEN2) | (1 << TXEN2);    // Set Baud rate    UBRR2 = 2;  // SPI clock running at 2.6MHz    // get an initial value for each channel. This ensures    // _count[] is never zero    for (uint8_t i=0; i<8; i++) {        uint16_t adc_tmp;        adc_tmp  = ADC_SPI_transfer(0) << 8;        adc_tmp |= ADC_SPI_transfer(adc_cmd[i + 1]);        _count[i] = 1;        _sum[i]   = adc_tmp;    }    last_ch6_micros = micros();    scheduler->register_process( AP_ADC_ADS7844::read );}// Read one channel valuedouble ADC::ch(uint8_t c){    uint16_t count;    uint32_t sum;    // Ensure we have at least one value    while (_count[c] == 0); // Waiting while    // grab the value with interrupts Disabled,and clear the count    cli();    count = _count[c];    sum   = _sum[c];    _count[c] = 0;    _sum[c]   = 0;    sei();    return ((double)sum)/count;}// See if Ch6() can return new databool ADC::available(const uint8_t *channelNumbers){    uint8_t i;    for (i=0; i<6; i++)    {        if (_count[channelNumbers[i]] == 0)        {            return false;        }    }    return true;}// Read 6 channel values// this assumes that the counts for all of the 6 channels are// equal. This will only be true if we always consistently access a// sensor by either Ch6() or Ch() and never mix them. If you mix them// then you will get very strange resultsuint32_t ADC::ch6(const uint8_t *channelNumbers,double *result){    uint16_t count[6];    uint32_t sum[6];    uint8_t i;    // Ensure we have at least one value    for (i=0; i<6; i++)    {        while (_count[channelNumbers[i]] == 0); // Waiting while    }    // Grab the values with interrupts Disabled,and clear the counts    cli();    for (i=0; i<6; i++)    {        count[i] = _count[channelNumbers[i]];        sum[i]   = _sum[channelNumbers[i]];        _count[channelNumbers[i]] = 0;        _sum[channelNumbers[i]]   = 0;    }    sei();    // Calculate averages. We keep this out of the cli region    // to prevent us stalling the ISR while doing the    // division. That costs us 36 bytes of stack,but I think its    // worth it.    for (i = 0; i < 6; i++)    {        result[i] = (sum[i] + count[i]) / (double)count[i];    }    // Return number of microseconds since last call    uint32_t us = micros();    uint32_t ret = us - last_ch6_micros;    last_ch6_micros = us;    return ret;}

提供错误报告：

ADC.cpp:10: error: expected unqualifIEd-ID before 'volatile'ADC.cpp:10: error: expected `)' before 'volatile'ADC.cpp:10: error: expected `)' before 'volatile'ADC.cpp:29: error: expected unqualifIEd-ID before 'volatile'ADC.cpp:29: error: expected `)' before 'volatile'ADC.cpp:29: error: expected `)' before 'volatile'ADC.cpp:39: error: expected unqualifIEd-ID before 'volatile'ADC.cpp:39: error: expected `)' before 'volatile'ADC.cpp:39: error: expected `)' before 'volatile'ADC.cpp:44: error: expected unqualifIEd-ID before 'volatile'ADC.cpp:44: error: expected `)' before 'volatile'ADC.cpp:44: error: expected `)' before 'volatile'

这有什么不对？为什么它指向我的恒定静态定义？为什么它讨厌我的3个类方法？为什么对于那个线路上不存在volatile的volatile会期望’)’？为什么期望一个不合格的ID(不应该是另一种方式)？

解决方法 ADC显然是AVR库下的保留字.我改变了我的班级名称,所有的错误都消失了.所有那些为不正确的班级名称而烦恼的人！

消息来源我发现它出了问题：第9个帖子是http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1283472517.

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