ATmega328p - 'volatile' 之前的预期不合格 ID
ATmega328p - Expected unqualified-id before 'volatile'
我正在为我的 ATmega328p 开发一个用于 OTA 更新的自定义引导加载程序。我正在从 Arduino 的 Optiboot 引导加载程序代码中获取帮助，对于 USART 部分，我编写了一个自定义头文件来处理 USART 通信。部分。这是代码（检查代码基本上是为了测试逻辑）-
bootuart.h
#ifndef _BOOT_UART_H
#define _BOOT_UART_H
#include <avr/io.h>
#if (SOFT_UART == 0)
#if (UART == 0)
#if defined(UDR0)
#define UART_SRA UCSR0A
#define UART_SRB UCSR0B
#define UART_SRC UCSR0C
#define UART_SRL UBRR0L
#define UART_UDR UDR0
#elif defined(UDR)
#define UART_SRA UCSRA
#define UART_SRB UCSRB
#define UART_SRC UCSRC
#define UART_SRL UBRRL
#define UART_UDR UDR
#elif defined(LINDAT)
#error UART == 0, but no LINDAT support in prog
#else
#error UART == 0, but no UART0 on device
#endif
#elif (UART == 1)
#if !defined(UDR1)
#error UART == 1, but no UART1 on device
#endif
#define UART_SRA UCSR1A
#define UART_SRB UCSR1B
#define UART_SRC UCSR1C
#define UART_SRL UBRR1L
#define UART_UDR UDR1
#elif (UART == 2)
#if !defined(UDR2)
#error UART == 2, but no UART2 on device
#endif
#define UART_SRA UCSR2A
#define UART_SRB UCSR2B
#define UART_SRC UCSR2C
#define UART_SRL UBRR2L
#define UART_UDR UDR2
#elif (UART == 3)
#if !defined(UDR3)
#error UART == 3, but no UART3 on device
#endif
#define UART_SRA UCSR3A
#define UART_SRB UCSR3B
#define UART_SRC UCSR3C
#define UART_SRL UBRR3L
#define UART_UDR UDR3
#endif
#endif
#ifdef __cplusplus
extern "C" {
#endif
void writeUSART(uint8_t);
#ifdef __cplusplus
}
#endif
#ifdef __cplusplus
extern "C" {
#endif
uint8_t readUSART(void);
#ifdef __cplusplus
}
#endif
#endif
bootuart.c
#include <avr/io.h>
#include "bootuart.h"
void writeUSART(uint8_t ch) {
#if (SOFTUART == 0)
#ifndef LINUART
while (!(UART_SRA & _BV(UDRE0)));
#endif
UART_UDR = ch;
#endif
}
uint8_t readUSART(void) {
uint8_t ch;
#if (SOFTUART == 0)
#ifndef LINUART
while(!(UART_SRA & _BV(RXC0)));
#endif
ch = UART_UDR;
#endif
return ch;
}
check.ino
#if !defined(SOFTUART)
#define SOFTUART 0
#endif
#if !defined(UART)
#define UART 0
#endif
#if !defined(SINGLESPEED)
#define SINGLESPEED 0
#endif
#include <avr/io.h>
#include "bootuart.h"
#ifndef BAUD_RATE
#if F_CPU >= 8000000L
#define BAUD_RATE 115200L // Highest rate Avrdude win32 can support
#elif F_CPU >= 1000000L
#define BAUD_RATE 9600L // 19200 also supported, but with significant error
#elif F_CPU >= 128000L
#define BAUD_RATE 4800L // Good for 128kHz internal RC
#else
#define BAUD_RATE 1200L // Good even at 32768Hz
#endif
#endif
#if (SOFTUART == 0)
#if SINGLESPEED
/* Single speed option */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 8L) / ((BAUD_RATE * 16L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(16 * ((BAUD_SETTING)+1)))
#else
/* Normal U2X usage */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 4L) / ((BAUD_RATE * 8L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(8 * ((BAUD_SETTING)+1)))
#endif
#if BAUD_ACTUAL <= BAUD_RATE
#define BAUD_ERROR (( 100*(BAUD_RATE - BAUD_ACTUAL) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
#error BAUD_RATE off by greater than -5%
#elif BAUD_ERROR >= 2 && !defined(PRODUCTION)
#warning BAUD_RATE off by greater than -2%
#endif
#else
#define BAUD_ERROR (( 100*(BAUD_ACTUAL - BAUD_RATE) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
#error BAUD_RATE off by greater than 5%
#elif BAUD_ERROR >= 2 && !defined(PRODUCTION)
#warning BAUD_RATE off by greater than 2%
#endif
#endif
#if BAUD_SETTING > 250
#error Unachievable baud rate (too slow) BAUD_RATE
#endif // baud rate slow check
#if (BAUD_SETTING - 1) < 3
#if BAUD_ERROR != 0 // permit high bitrates (ie 1Mbps@16MHz) if error is zero
#error Unachievable baud rate (too fast) BAUD_RATE
#endif
#endif // baud rate fast check
#endif // SOFTUART
#if (SOFTUART == 0)
#if defined(__AVR_ATmega8__) || defined (__AVR_ATmega8515__) || \
defined (__AVR_ATmega8535__) || defined (__AVR_ATmega16__) || \
defined (__AVR_ATmega32__)
#if (SINGLESPEED == 0)
UCSRA = _BV(U2X); //Double speed mode USART
#endif //singlespeed
UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
UBRRL = (uint8_t)BAUD_SETTING;
#else // mega8/etc
#ifdef LINUART
//DDRB|=3;
LINCR = (1 << LSWRES);
//LINBRRL = (((F_CPU * 10L / 32L / BAUD_RATE) + 5L) / 10L) - 1;
LINBRRL=(uint8_t)BAUD_SETTING;
LINBTR = (1 << LDISR) | (8 << LBT0);
LINCR = _BV(LENA) | _BV(LCMD2) | _BV(LCMD1) | _BV(LCMD0);
LINDAT=0;
#else
#if (SINGLESPEED == 0)
UART_SRA = _BV(U2X0); //Double speed mode USART0
#endif
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)BAUD_SETTING;
#endif // LINUART
#endif // mega8/etc
#endif // softUART
int main(void)
{
while(1){
writeUSART(readUSART());
}
return 0;
}
问题：
现在，问题是每当我编译代码时，都会收到如下错误：-
bootuart.h:8:24: error: expected unqualified-id before 'volatile'
#define UART_SRA UCSR0A
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:82:5: note: in expansion of macro 'UART_SRA'
UART_SRA = _BV(U2X0); //Double speed mode USART0
^~~~~~~~
bootuart.h:8:24: error: expected ')' before 'volatile'
#define UART_SRA UCSR0A
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:82:5: note: in expansion of macro 'UART_SRA'
UART_SRA = _BV(U2X0); //Double speed mode USART0
^~~~~~~~
bootuart.h:8:24: error: expected ')' before 'volatile'
#define UART_SRA UCSR0A
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:82:5: note: in expansion of macro 'UART_SRA'
UART_SRA = _BV(U2X0); //Double speed mode USART0
^~~~~~~~
bootuart.h:9:24: error: expected unqualified-id before 'volatile'
#define UART_SRB UCSR0B
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:84:4: note: in expansion of macro 'UART_SRB'
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
^~~~~~~~
bootuart.h:9:24: error: expected ')' before 'volatile'
#define UART_SRB UCSR0B
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:84:4: note: in expansion of macro 'UART_SRB'
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
^~~~~~~~
bootuart.h:9:24: error: expected ')' before 'volatile'
#define UART_SRB UCSR0B
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:84:4: note: in expansion of macro 'UART_SRB'
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
^~~~~~~~
bootuart.h:10:24: error: expected unqualified-id before 'volatile'
#define UART_SRC UCSR0C
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:85:4: note: in expansion of macro 'UART_SRC'
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
^~~~~~~~
bootuart.h:10:24: error: expected ')' before 'volatile'
#define UART_SRC UCSR0C
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:85:4: note: in expansion of macro 'UART_SRC'
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
^~~~~~~~
bootuart.h:10:24: error: expected ')' before 'volatile'
#define UART_SRC UCSR0C
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:85:4: note: in expansion of macro 'UART_SRC'
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
^~~~~~~~
bootuart.h:11:24: error: expected unqualified-id before 'volatile'
#define UART_SRL UBRR0L
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:86:4: note: in expansion of macro 'UART_SRL'
UART_SRL = (uint8_t)BAUD_SETTING;
^~~~~~~~
bootuart.h:11:24: error: expected ')' before 'volatile'
#define UART_SRL UBRR0L
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:86:4: note: in expansion of macro 'UART_SRL'
UART_SRL = (uint8_t)BAUD_SETTING;
^~~~~~~~
bootuart.h:11:24: error: expected ')' before 'volatile'
#define UART_SRL UBRR0L
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:86:4: note: in expansion of macro 'UART_SRL'
UART_SRL = (uint8_t)BAUD_SETTING;
^~~~~~~~
exit status 1
expected unqualified-id before 'volatile'
我已经在某个地方检查了这个问题的许多其他链接，但其中 none 有帮助。对于 Whosebug 中的 1 个问题 - Question，根据答案，我检查了我的 #define 的 none 是否与我的代码中包含的 libs 文件中的任何其他标识符匹配。但是，问题依然存在。
P.S：我什至尝试将#define 标识符名称更改为其他标识符名称，但没有成功。此外，我已经尝试使用 ATMEL 工作室的代码。没有好处。
任何人都可以指出，我的代码有什么问题吗？因为如果它在 Optiboot 中工作，那么它也应该在这里工作，这就是我的感受。
如有任何帮助，我们将不胜感激。提前致谢。
经过一些替换（不是全部）后你会得到这个：
#if !defined(SOFTUART)
#define SOFTUART 0
#endif
#if !defined(UART)
#define UART 0
#endif
#if !defined(SINGLESPEED)
#define SINGLESPEED 0
#endif
#include <avr/io.h>
#include "bootuart.h"
UART_SRA = _BV(U2X0); //Double speed mode USART0
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)BAUD_SETTING;
int main(void)
{
while(1){
writeUSART(readUSART());
}
return 0;
}
正如您可能知道的，您不能在函数之外做任何事情。你必须把它放到主块中，或者让它成为在主函数中调用的设置函数：
void setup() {
#if (SOFTUART == 0)
#if defined(__AVR_ATmega8__) || defined (__AVR_ATmega8515__) || \
defined (__AVR_ATmega8535__) || defined (__AVR_ATmega16__) || \
defined (__AVR_ATmega32__)
#if (SINGLESPEED == 0)
UCSRA = _BV(U2X); //Double speed mode USART
#endif //singlespeed
UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
UBRRL = (uint8_t)BAUD_SETTING;
#else // mega8/etc
#ifdef LINUART
//DDRB|=3;
LINCR = (1 << LSWRES);
//LINBRRL = (((F_CPU * 10L / 32L / BAUD_RATE) + 5L) / 10L) - 1;
LINBRRL=(uint8_t)BAUD_SETTING;
LINBTR = (1 << LDISR) | (8 << LBT0);
LINCR = _BV(LENA) | _BV(LCMD2) | _BV(LCMD1) | _BV(LCMD0);
LINDAT=0;
#else
#if (SINGLESPEED == 0)
UART_SRA = _BV(U2X0); //Double speed mode USART0
#endif
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)BAUD_SETTING;
#endif // LINUART
#endif // mega8/etc
#endif // softUART
} // setup()
int main() {
setup();
while (1) {
} // while
} // main()
顺便说一句：optiboot 有一点点不同——它在 main 函数里面
我正在为我的 ATmega328p 开发一个用于 OTA 更新的自定义引导加载程序。我正在从 Arduino 的 Optiboot 引导加载程序代码中获取帮助，对于 USART 部分，我编写了一个自定义头文件来处理 USART 通信。部分。这是代码（检查代码基本上是为了测试逻辑）-
bootuart.h
#ifndef _BOOT_UART_H
#define _BOOT_UART_H
#include <avr/io.h>
#if (SOFT_UART == 0)
#if (UART == 0)
#if defined(UDR0)
#define UART_SRA UCSR0A
#define UART_SRB UCSR0B
#define UART_SRC UCSR0C
#define UART_SRL UBRR0L
#define UART_UDR UDR0
#elif defined(UDR)
#define UART_SRA UCSRA
#define UART_SRB UCSRB
#define UART_SRC UCSRC
#define UART_SRL UBRRL
#define UART_UDR UDR
#elif defined(LINDAT)
#error UART == 0, but no LINDAT support in prog
#else
#error UART == 0, but no UART0 on device
#endif
#elif (UART == 1)
#if !defined(UDR1)
#error UART == 1, but no UART1 on device
#endif
#define UART_SRA UCSR1A
#define UART_SRB UCSR1B
#define UART_SRC UCSR1C
#define UART_SRL UBRR1L
#define UART_UDR UDR1
#elif (UART == 2)
#if !defined(UDR2)
#error UART == 2, but no UART2 on device
#endif
#define UART_SRA UCSR2A
#define UART_SRB UCSR2B
#define UART_SRC UCSR2C
#define UART_SRL UBRR2L
#define UART_UDR UDR2
#elif (UART == 3)
#if !defined(UDR3)
#error UART == 3, but no UART3 on device
#endif
#define UART_SRA UCSR3A
#define UART_SRB UCSR3B
#define UART_SRC UCSR3C
#define UART_SRL UBRR3L
#define UART_UDR UDR3
#endif
#endif
#ifdef __cplusplus
extern "C" {
#endif
void writeUSART(uint8_t);
#ifdef __cplusplus
}
#endif
#ifdef __cplusplus
extern "C" {
#endif
uint8_t readUSART(void);
#ifdef __cplusplus
}
#endif
#endif
bootuart.c
#include <avr/io.h>
#include "bootuart.h"
void writeUSART(uint8_t ch) {
#if (SOFTUART == 0)
#ifndef LINUART
while (!(UART_SRA & _BV(UDRE0)));
#endif
UART_UDR = ch;
#endif
}
uint8_t readUSART(void) {
uint8_t ch;
#if (SOFTUART == 0)
#ifndef LINUART
while(!(UART_SRA & _BV(RXC0)));
#endif
ch = UART_UDR;
#endif
return ch;
}
check.ino
#if !defined(SOFTUART)
#define SOFTUART 0
#endif
#if !defined(UART)
#define UART 0
#endif
#if !defined(SINGLESPEED)
#define SINGLESPEED 0
#endif
#include <avr/io.h>
#include "bootuart.h"
#ifndef BAUD_RATE
#if F_CPU >= 8000000L
#define BAUD_RATE 115200L // Highest rate Avrdude win32 can support
#elif F_CPU >= 1000000L
#define BAUD_RATE 9600L // 19200 also supported, but with significant error
#elif F_CPU >= 128000L
#define BAUD_RATE 4800L // Good for 128kHz internal RC
#else
#define BAUD_RATE 1200L // Good even at 32768Hz
#endif
#endif
#if (SOFTUART == 0)
#if SINGLESPEED
/* Single speed option */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 8L) / ((BAUD_RATE * 16L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(16 * ((BAUD_SETTING)+1)))
#else
/* Normal U2X usage */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 4L) / ((BAUD_RATE * 8L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(8 * ((BAUD_SETTING)+1)))
#endif
#if BAUD_ACTUAL <= BAUD_RATE
#define BAUD_ERROR (( 100*(BAUD_RATE - BAUD_ACTUAL) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
#error BAUD_RATE off by greater than -5%
#elif BAUD_ERROR >= 2 && !defined(PRODUCTION)
#warning BAUD_RATE off by greater than -2%
#endif
#else
#define BAUD_ERROR (( 100*(BAUD_ACTUAL - BAUD_RATE) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
#error BAUD_RATE off by greater than 5%
#elif BAUD_ERROR >= 2 && !defined(PRODUCTION)
#warning BAUD_RATE off by greater than 2%
#endif
#endif
#if BAUD_SETTING > 250
#error Unachievable baud rate (too slow) BAUD_RATE
#endif // baud rate slow check
#if (BAUD_SETTING - 1) < 3
#if BAUD_ERROR != 0 // permit high bitrates (ie 1Mbps@16MHz) if error is zero
#error Unachievable baud rate (too fast) BAUD_RATE
#endif
#endif // baud rate fast check
#endif // SOFTUART
#if (SOFTUART == 0)
#if defined(__AVR_ATmega8__) || defined (__AVR_ATmega8515__) || \
defined (__AVR_ATmega8535__) || defined (__AVR_ATmega16__) || \
defined (__AVR_ATmega32__)
#if (SINGLESPEED == 0)
UCSRA = _BV(U2X); //Double speed mode USART
#endif //singlespeed
UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
UBRRL = (uint8_t)BAUD_SETTING;
#else // mega8/etc
#ifdef LINUART
//DDRB|=3;
LINCR = (1 << LSWRES);
//LINBRRL = (((F_CPU * 10L / 32L / BAUD_RATE) + 5L) / 10L) - 1;
LINBRRL=(uint8_t)BAUD_SETTING;
LINBTR = (1 << LDISR) | (8 << LBT0);
LINCR = _BV(LENA) | _BV(LCMD2) | _BV(LCMD1) | _BV(LCMD0);
LINDAT=0;
#else
#if (SINGLESPEED == 0)
UART_SRA = _BV(U2X0); //Double speed mode USART0
#endif
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)BAUD_SETTING;
#endif // LINUART
#endif // mega8/etc
#endif // softUART
int main(void)
{
while(1){
writeUSART(readUSART());
}
return 0;
}
问题： 现在，问题是每当我编译代码时，都会收到如下错误：-
bootuart.h:8:24: error: expected unqualified-id before 'volatile'
#define UART_SRA UCSR0A
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:82:5: note: in expansion of macro 'UART_SRA'
UART_SRA = _BV(U2X0); //Double speed mode USART0
^~~~~~~~
bootuart.h:8:24: error: expected ')' before 'volatile'
#define UART_SRA UCSR0A
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:82:5: note: in expansion of macro 'UART_SRA'
UART_SRA = _BV(U2X0); //Double speed mode USART0
^~~~~~~~
bootuart.h:8:24: error: expected ')' before 'volatile'
#define UART_SRA UCSR0A
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:82:5: note: in expansion of macro 'UART_SRA'
UART_SRA = _BV(U2X0); //Double speed mode USART0
^~~~~~~~
bootuart.h:9:24: error: expected unqualified-id before 'volatile'
#define UART_SRB UCSR0B
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:84:4: note: in expansion of macro 'UART_SRB'
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
^~~~~~~~
bootuart.h:9:24: error: expected ')' before 'volatile'
#define UART_SRB UCSR0B
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:84:4: note: in expansion of macro 'UART_SRB'
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
^~~~~~~~
bootuart.h:9:24: error: expected ')' before 'volatile'
#define UART_SRB UCSR0B
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:84:4: note: in expansion of macro 'UART_SRB'
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
^~~~~~~~
bootuart.h:10:24: error: expected unqualified-id before 'volatile'
#define UART_SRC UCSR0C
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:85:4: note: in expansion of macro 'UART_SRC'
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
^~~~~~~~
bootuart.h:10:24: error: expected ')' before 'volatile'
#define UART_SRC UCSR0C
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:85:4: note: in expansion of macro 'UART_SRC'
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
^~~~~~~~
bootuart.h:10:24: error: expected ')' before 'volatile'
#define UART_SRC UCSR0C
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:85:4: note: in expansion of macro 'UART_SRC'
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
^~~~~~~~
bootuart.h:11:24: error: expected unqualified-id before 'volatile'
#define UART_SRL UBRR0L
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:86:4: note: in expansion of macro 'UART_SRL'
UART_SRL = (uint8_t)BAUD_SETTING;
^~~~~~~~
bootuart.h:11:24: error: expected ')' before 'volatile'
#define UART_SRL UBRR0L
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:86:4: note: in expansion of macro 'UART_SRL'
UART_SRL = (uint8_t)BAUD_SETTING;
^~~~~~~~
bootuart.h:11:24: error: expected ')' before 'volatile'
#define UART_SRL UBRR0L
^
E:\SPIDER\OTA_Programming_Module\Misc\check\check.ino:86:4: note: in expansion of macro 'UART_SRL'
UART_SRL = (uint8_t)BAUD_SETTING;
^~~~~~~~
exit status 1
expected unqualified-id before 'volatile'
我已经在某个地方检查了这个问题的许多其他链接，但其中 none 有帮助。对于 Whosebug 中的 1 个问题 - Question，根据答案，我检查了我的 #define 的 none 是否与我的代码中包含的 libs 文件中的任何其他标识符匹配。但是，问题依然存在。
P.S：我什至尝试将#define 标识符名称更改为其他标识符名称，但没有成功。此外，我已经尝试使用 ATMEL 工作室的代码。没有好处。
任何人都可以指出，我的代码有什么问题吗？因为如果它在 Optiboot 中工作，那么它也应该在这里工作，这就是我的感受。
如有任何帮助，我们将不胜感激。提前致谢。
经过一些替换（不是全部）后你会得到这个：
#if !defined(SOFTUART)
#define SOFTUART 0
#endif
#if !defined(UART)
#define UART 0
#endif
#if !defined(SINGLESPEED)
#define SINGLESPEED 0
#endif
#include <avr/io.h>
#include "bootuart.h"
UART_SRA = _BV(U2X0); //Double speed mode USART0
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)BAUD_SETTING;
int main(void)
{
while(1){
writeUSART(readUSART());
}
return 0;
}
正如您可能知道的，您不能在函数之外做任何事情。你必须把它放到主块中，或者让它成为在主函数中调用的设置函数：
void setup() {
#if (SOFTUART == 0)
#if defined(__AVR_ATmega8__) || defined (__AVR_ATmega8515__) || \
defined (__AVR_ATmega8535__) || defined (__AVR_ATmega16__) || \
defined (__AVR_ATmega32__)
#if (SINGLESPEED == 0)
UCSRA = _BV(U2X); //Double speed mode USART
#endif //singlespeed
UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
UBRRL = (uint8_t)BAUD_SETTING;
#else // mega8/etc
#ifdef LINUART
//DDRB|=3;
LINCR = (1 << LSWRES);
//LINBRRL = (((F_CPU * 10L / 32L / BAUD_RATE) + 5L) / 10L) - 1;
LINBRRL=(uint8_t)BAUD_SETTING;
LINBTR = (1 << LDISR) | (8 << LBT0);
LINCR = _BV(LENA) | _BV(LCMD2) | _BV(LCMD1) | _BV(LCMD0);
LINDAT=0;
#else
#if (SINGLESPEED == 0)
UART_SRA = _BV(U2X0); //Double speed mode USART0
#endif
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
UART_SRL = (uint8_t)BAUD_SETTING;
#endif // LINUART
#endif // mega8/etc
#endif // softUART
} // setup()
int main() {
setup();
while (1) {
} // while
} // main()
顺便说一句：optiboot 有一点点不同——它在 main 函数里面