Issue with " Error: '_asm': undefined identifier "
Issue with " Error: '_asm': undefined identifier "
我已经编写了代码，使 8051 微控制器能够与 LCD 接口，并在 LCD 上显示以 8 位二进制值读取的温度。代码在运行时能够在 LCD 上显示文本，但是，当引入允许读取温度的代码时，程序中断了。错误似乎集中在从 ADC 读取温度的函数周围，并且似乎与“_asm”有关，这是我以前从未处理过的。下面列出了错误：
compiling main.c...
main.c(72): error C231: 'get_temp': redefinition
main.c(74): error C141: syntax error near 'int', expected '__asm'
main.c(74): error C202: 'readvalue': undefined identifier
main.c(75): error C141: syntax error near 'int', expected '__asm'
main.c(75): error C202: 'temp': undefined identifier
main.c(76): error C141: syntax error near 'int', expected '__asm'
main.c(76): error C202: 'binaryvalue': undefined identifier
main.c(76): error C141: syntax error near '{', expected 'sizeof'
main.c(76): error C141: syntax error near '}', expected ';'
main.c(77): error C141: syntax error near 'int', expected '__asm'
main.c(77): error C141: syntax error near '{', expected 'sizeof'
main.c(82): error C141: syntax error near '}', expected ';'
main.c(83): error C141: syntax error near '{', expected 'sizeof'
main.c(83): error C141: syntax error near ')', expected ';'
main.c(85): error C202: 'temp': undefined identifier
main.c(88): error C202: 'temp': undefined identifier
main.c(89): error C231: 'get_temp': redefinition
main.c(118): error C141: syntax error near 'int', expected '__asm'
main.c(118): error C202: 'atemp': undefined identifier
main.c(119): error C202: 'atemp': undefined identifier
main.c(120): error C202: 'atemp': undefined identifier
该代码已在 Keil uVision 中开发，如下所示。函数原型被注释掉，因为它们会导致程序出现更多问题，并且在注释掉时，一些错误已得到解决：
#include<reg51.h>
#include<stdio.h>
/********************************************* LCD control signals declaration ***************************************************/
sbit RS = P0^0; //
sbit RW = P0^1; // Read/write line
sbit Enable = P0^2; // Enable line
#define LCD_PORT P2 // define port
/********************************************* LCD function prototypes ************************************************/
//void send_cmd(unsigned char);
//void send_char(unsigned char);
//void send_int()
//void LCD_init(void);
//void delayms(unsigned int);
//int get_temp();
////int get_humidity();
/******************************************* delayms Function declaration***********************************************/
void delayms(unsigned int val)
{
unsigned int i,j;
for(i=0;i<=val;i++)
{
for(j=0;j<=2;j++) ;
//_nop_(); // no operation produce 1us time delay
}
}
/*********************************************LCD Command Sending Function declaration********************************/
void send_cmd(unsigned char Command)
{
LCD_PORT = Command;
RS = 0; // Select Command Register
RW = 0; // write operation
Enable = 1; // High to Low pulse provided on the enable pin with nearly 1ms(>450ns)
delayms(1); // 1 millisec delay
Enable = 0;
}
/********************************************* LCD Initialization Function declaration ********************************/
void LCD_init()
{
send_cmd(0x38); // configuring LCD as 2 line 5x7 matrix
send_cmd(0x0E); // Display on, Cursor blinking
send_cmd(0x01); // Clear Display Screen
send_cmd(0x06); // Increment Cursor (Right side)
}
void send_char(unsigned char character)
{
LCD_PORT = character;
RS = 1; // Select Data Register
RW = 0; // write operation
Enable = 1; // High to Low pulse provided on the enable pin with nearly 1ms(>450ns)
delayms(1); // 1 millisec delay
Enable = 0;
delayms(10); // 100 millisec delay
}
/****************************************** Temperature Function Declaration ********************************************/
void get_temp(){
P1 = 0xFF;
int readvalue = P1;
int temp;
int binaryvalue[70] = {01000001,00100001,01100001,00010001,10010001,11010001,10110001,11110001,00001001,01001001,00101001,01101001,11101001,10011001,01011001,00111001,01111001,11111001,10000101,01000101,00100101,10100101,01100101,00010101,10010101,11010101,00110101,01110101,01110101,00001101,10001101,01001101,11001101,00101101,01101101,01101101,11101101,00011101,01011101,01011101,11011101,00111101,10111101,01111101,11111101,11111101,00000011,10000011,10000011,01000011,11000011,00100011,00100011,10100011,10100011,01100011,11100011,11100011,11100011,00010011,00010011,10010011,10010011,01010011,01010011,11010011,11010011,11010011,00110011,00110011,10110011};
int temperature[70] = {-20,-19,-18,-17,-16,-15,-14,-13,
-12,-10,-9,-8,-7,-6,-5,-4,-3,-2,-1,
0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,
15,16,17,18,19,20,21,22,23,24,25,26,
27,28,29,30,31,32,33,34,35,36,37,38,
39,40,41,42,43,44,45,46,47,48,49,50};
for(i=0;i<sizeof{binaryvalue};i++){
if(readvalue == binaryvalue[i]){
temp = temperature[i];
}
}
return temp;
}
/********************************************* Main Funciton declaration ***********************************************/
void main()
{
LCD_PORT = 0x00; // Make the port as output port
LCD_init(); // LCD initialization
send_cmd(0x80); // Force cursor to beginning of 1st line, if the number is 0x83 then force the cursor to 53rd position
delayms(100); // Delay of 100millisec
send_char('T');
send_char('H');
send_char('E');
send_char('R');
send_char('M'); // Send data
send_char('I');
send_char('S');
send_char('T');
send_char('O');
send_char('R'); // Send data
send_cmd(0xC0); // Force cursor to beginning of 2nd line
delayms(100); // Delay of 100millisec
send_char('V'); // Send data
send_char('A'); // Send data
send_char('L'); // Send data
send_char('U'); // Send data
send_char('E'); // Send data
send_char(':'); // Send data
int atemp = get_temp();
while (atemp > 0){
int k = atemp % 10;
char send_x;
itoa(k,send_x,10);
send_char(send_x);
temp /= 10;
}
//}
}
由于我对 C 的了解有限，因此将不胜感激。提前致谢。
_asm 标记内联汇编，正确的语法取决于您使用的机器（What is the difference between 'asm', '__asm' and '__asm__'? ). i do not know where you got the library with the LCD driver code from but inline assembly in Keil is described in https://www.keil.com/support/man/docs/armcc/armcc_chr1359124246903.htm and https://www.keil.com/support/man/docs/c51/c51_ap_ctoasm.htm（对于 8051）
错误在行
void get_temp(){
P1 = 0xFF;
_asm int readvalue = P1;
_asm int temp;
我认为您想读取或修改 P1 特殊功能寄存器 (SFR) 因为它与您的温度传感器有连接，为此请参阅 https://www.includehelp.com/embedded-system/accessing-ports-and-pins-in-8051-microcontroller.aspx
此外，您尝试将 8 位值转换为至少 16 位的 int...
另外你尝试write/read锁存P1，而不是读取它的值(https://developer.arm.com/documentation/ka004317/latest)
我已经编写了代码，使 8051 微控制器能够与 LCD 接口，并在 LCD 上显示以 8 位二进制值读取的温度。代码在运行时能够在 LCD 上显示文本，但是，当引入允许读取温度的代码时，程序中断了。错误似乎集中在从 ADC 读取温度的函数周围，并且似乎与“_asm”有关，这是我以前从未处理过的。下面列出了错误：
compiling main.c...
main.c(72): error C231: 'get_temp': redefinition
main.c(74): error C141: syntax error near 'int', expected '__asm'
main.c(74): error C202: 'readvalue': undefined identifier
main.c(75): error C141: syntax error near 'int', expected '__asm'
main.c(75): error C202: 'temp': undefined identifier
main.c(76): error C141: syntax error near 'int', expected '__asm'
main.c(76): error C202: 'binaryvalue': undefined identifier
main.c(76): error C141: syntax error near '{', expected 'sizeof'
main.c(76): error C141: syntax error near '}', expected ';'
main.c(77): error C141: syntax error near 'int', expected '__asm'
main.c(77): error C141: syntax error near '{', expected 'sizeof'
main.c(82): error C141: syntax error near '}', expected ';'
main.c(83): error C141: syntax error near '{', expected 'sizeof'
main.c(83): error C141: syntax error near ')', expected ';'
main.c(85): error C202: 'temp': undefined identifier
main.c(88): error C202: 'temp': undefined identifier
main.c(89): error C231: 'get_temp': redefinition
main.c(118): error C141: syntax error near 'int', expected '__asm'
main.c(118): error C202: 'atemp': undefined identifier
main.c(119): error C202: 'atemp': undefined identifier
main.c(120): error C202: 'atemp': undefined identifier
该代码已在 Keil uVision 中开发，如下所示。函数原型被注释掉，因为它们会导致程序出现更多问题，并且在注释掉时，一些错误已得到解决：
#include<reg51.h>
#include<stdio.h>
/********************************************* LCD control signals declaration ***************************************************/
sbit RS = P0^0; //
sbit RW = P0^1; // Read/write line
sbit Enable = P0^2; // Enable line
#define LCD_PORT P2 // define port
/********************************************* LCD function prototypes ************************************************/
//void send_cmd(unsigned char);
//void send_char(unsigned char);
//void send_int()
//void LCD_init(void);
//void delayms(unsigned int);
//int get_temp();
////int get_humidity();
/******************************************* delayms Function declaration***********************************************/
void delayms(unsigned int val)
{
unsigned int i,j;
for(i=0;i<=val;i++)
{
for(j=0;j<=2;j++) ;
//_nop_(); // no operation produce 1us time delay
}
}
/*********************************************LCD Command Sending Function declaration********************************/
void send_cmd(unsigned char Command)
{
LCD_PORT = Command;
RS = 0; // Select Command Register
RW = 0; // write operation
Enable = 1; // High to Low pulse provided on the enable pin with nearly 1ms(>450ns)
delayms(1); // 1 millisec delay
Enable = 0;
}
/********************************************* LCD Initialization Function declaration ********************************/
void LCD_init()
{
send_cmd(0x38); // configuring LCD as 2 line 5x7 matrix
send_cmd(0x0E); // Display on, Cursor blinking
send_cmd(0x01); // Clear Display Screen
send_cmd(0x06); // Increment Cursor (Right side)
}
void send_char(unsigned char character)
{
LCD_PORT = character;
RS = 1; // Select Data Register
RW = 0; // write operation
Enable = 1; // High to Low pulse provided on the enable pin with nearly 1ms(>450ns)
delayms(1); // 1 millisec delay
Enable = 0;
delayms(10); // 100 millisec delay
}
/****************************************** Temperature Function Declaration ********************************************/
void get_temp(){
P1 = 0xFF;
int readvalue = P1;
int temp;
int binaryvalue[70] = {01000001,00100001,01100001,00010001,10010001,11010001,10110001,11110001,00001001,01001001,00101001,01101001,11101001,10011001,01011001,00111001,01111001,11111001,10000101,01000101,00100101,10100101,01100101,00010101,10010101,11010101,00110101,01110101,01110101,00001101,10001101,01001101,11001101,00101101,01101101,01101101,11101101,00011101,01011101,01011101,11011101,00111101,10111101,01111101,11111101,11111101,00000011,10000011,10000011,01000011,11000011,00100011,00100011,10100011,10100011,01100011,11100011,11100011,11100011,00010011,00010011,10010011,10010011,01010011,01010011,11010011,11010011,11010011,00110011,00110011,10110011};
int temperature[70] = {-20,-19,-18,-17,-16,-15,-14,-13,
-12,-10,-9,-8,-7,-6,-5,-4,-3,-2,-1,
0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,
15,16,17,18,19,20,21,22,23,24,25,26,
27,28,29,30,31,32,33,34,35,36,37,38,
39,40,41,42,43,44,45,46,47,48,49,50};
for(i=0;i<sizeof{binaryvalue};i++){
if(readvalue == binaryvalue[i]){
temp = temperature[i];
}
}
return temp;
}
/********************************************* Main Funciton declaration ***********************************************/
void main()
{
LCD_PORT = 0x00; // Make the port as output port
LCD_init(); // LCD initialization
send_cmd(0x80); // Force cursor to beginning of 1st line, if the number is 0x83 then force the cursor to 53rd position
delayms(100); // Delay of 100millisec
send_char('T');
send_char('H');
send_char('E');
send_char('R');
send_char('M'); // Send data
send_char('I');
send_char('S');
send_char('T');
send_char('O');
send_char('R'); // Send data
send_cmd(0xC0); // Force cursor to beginning of 2nd line
delayms(100); // Delay of 100millisec
send_char('V'); // Send data
send_char('A'); // Send data
send_char('L'); // Send data
send_char('U'); // Send data
send_char('E'); // Send data
send_char(':'); // Send data
int atemp = get_temp();
while (atemp > 0){
int k = atemp % 10;
char send_x;
itoa(k,send_x,10);
send_char(send_x);
temp /= 10;
}
//}
}
由于我对 C 的了解有限，因此将不胜感激。提前致谢。
_asm 标记内联汇编，正确的语法取决于您使用的机器（What is the difference between 'asm', '__asm' and '__asm__'? ). i do not know where you got the library with the LCD driver code from but inline assembly in Keil is described in https://www.keil.com/support/man/docs/armcc/armcc_chr1359124246903.htm and https://www.keil.com/support/man/docs/c51/c51_ap_ctoasm.htm（对于 8051）
错误在行
void get_temp(){
P1 = 0xFF;
_asm int readvalue = P1;
_asm int temp;
我认为您想读取或修改 P1 特殊功能寄存器 (SFR) 因为它与您的温度传感器有连接，为此请参阅 https://www.includehelp.com/embedded-system/accessing-ports-and-pins-in-8051-microcontroller.aspx
此外，您尝试将 8 位值转换为至少 16 位的 int...
另外你尝试write/read锁存P1，而不是读取它的值(https://developer.arm.com/documentation/ka004317/latest)