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i need some help, how i can solve the error conflicting of types of 'read' void read(){ ? these code may combining form GTK and BME280 barometer sensor. the codes may work if i originally run separatly. i got some problem when i trying combine it i will share my code. the problem will say that....


///
280b.c: At top level:
280b.c:158:6: error: conflicting types for ‘read’
void read(){
^~~~
In file included from /usr/include/glib-2.0/gio/gcredentials.h:32,
from /usr/include/glib-2.0/gio/gio.h:46,
from /usr/include/gtk-2.0/gdk/gdkapplaunchcontext.h:30,
from /usr/include/gtk-2.0/gdk/gdk.h:32,
from /usr/include/gtk-2.0/gtk/gtk.h:32,
from 280b.c:4:
/usr/include/unistd.h:360:16: note: previous declaration of ‘read’ was here
extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur;
///


bmp280 code from sunfounder

/**********************************************************************
* Filename    : bmp280.c
* Description : Simple use for bmp280 through i2c bus
* Author      : Cavon
* Brand       : SunFounder
* E-mail      : support@sunfounder.com
* Website     : www.sunfounder.com
* Update      : Cavon    2016-10-09    New release
**********************************************************************/

#include <stdio.h>
#include <wiringPiI2C.h>
#include <math.h>

#define QNH             1020

// Power mode
//#define POWER_MODE    0   // sleep mode
//#define POWER_MODE    1   // forced mode
//#define POWER_MODE    2   // forced mode
#define POWER_MODE      3   // normal mode

// Temperature resolution
//#define OSRS_T    0    // skipped
//#define OSRS_T    1    // 16 Bit
//#define OSRS_T    2    // 17 Bit
//#define OSRS_T    3    // 18 Bit
//#define OSRS_T    4    // 19 Bit
#define OSRS_T      5    // 20 Bit

// Pressure resolution
//#define OSRS_P    0   // pressure measurement skipped
//#define OSRS_P    1   // 16 Bit ultra low power
//#define OSRS_P    2   // 17 Bit low power
//#define OSRS_P    3   // 18 Bit standard resolution
//#define OSRS_P    4   // 19 Bit high resolution
#define OSRS_P      5   // 20 Bit ultra high resolution

// Filter settings
//#define FILTER    0   //
//#define FILTER    1   //
//#define FILTER    2   //
//#define FILTER    3   //
#define FILTER      4   //
//#define FILTER    5   //
//#define FILTER    6   //
//#define FILTER    7   //

// Standby settings
//#define T_SB      0     // 000 0,5ms
//#define T_SB      1     // 001 62.5 ms
//#define T_SB      2     // 010 125 ms
//#define T_SB      3     // 011 250ms
#define T_SB        4     // 100 500ms
//#define T_SB      5     // 101 1000ms
//#define T_SB      6     // 110 2000ms
//#define T_SB      7     // 111 4000ms

#define BMP280_REGISTER_DIG_T1				0x88
#define BMP280_REGISTER_DIG_T2				0x8A
#define BMP280_REGISTER_DIG_T3				0x8C
#define BMP280_REGISTER_DIG_P1				0x8E
#define BMP280_REGISTER_DIG_P2				0x90
#define BMP280_REGISTER_DIG_P3				0x92
#define BMP280_REGISTER_DIG_P4				0x94
#define BMP280_REGISTER_DIG_P5				0x96
#define BMP280_REGISTER_DIG_P6				0x98
#define BMP280_REGISTER_DIG_P7				0x9A
#define BMP280_REGISTER_DIG_P8				0x9C
#define BMP280_REGISTER_DIG_P9				0x9E
#define BMP280_REGISTER_CHIPID				0xD0
#define BMP280_REGISTER_VERSION				0xD1
#define BMP280_REGISTER_SOFTRESET			0xE0
#define BMP280_REGISTER_CONTROL				0xF4
#define BMP280_REGISTER_CONFIG				0xF5
#define BMP280_REGISTER_STATUS				0xF3
#define BMP280_REGISTER_TEMPDATA_MSB		0xFA
#define BMP280_REGISTER_TEMPDATA_LSB		0xFB
#define BMP280_REGISTER_TEMPDATA_XLSB		0xFC
#define BMP280_REGISTER_PRESSDATA_MSB		0xF7
#define BMP280_REGISTER_PRESSDATA_LSB		0xF8
#define BMP280_REGISTER_PRESSDATA_XLSB		0xF9

int CONFIG = (T_SB <<5) + (FILTER <<2); // combine bits for config
int CTRL_MEAS = (OSRS_T <<5) + (OSRS_P <<2) + POWER_MODE; // combine bits for ctrl_meas

int bmp280 = 0;
struct {
	int chip_id;
	int chip_version;
	double temperature;
	double pressure;
	double altitude;
} bmp;

int dig_T1 = 0;
int dig_T2 = 0;
int dig_T3 = 0;
int dig_P1 = 0;
int dig_P2 = 0;
int dig_P3 = 0;
int dig_P4 = 0;
int dig_P5 = 0;
int dig_P6 = 0;
int dig_P7 = 0;
int dig_P8 = 0;
int dig_P9 = 0;

void write_byte_data(int reg, int value){
	wiringPiI2CWriteReg8(bmp280, reg, value);
}

int read_byte_data(int reg){
	int result;
	result = wiringPiI2CReadReg8(bmp280, reg);
	return result;
}

int read_word_data_unsigned(int reg){
	int result;
	result = wiringPiI2CReadReg16(bmp280, reg);
	return result;
}

int read_word_data_signed(int reg){
	int result;
	result = read_word_data_unsigned(reg);
	if (result > 32767){
		result -= 65536;
	}
	return result;
}

void read_id(self){
	int REG_ID     = 0xD0;
	int result;
	result = read_word_data_unsigned(REG_ID);
	bmp.chip_id = result & 0x00FF;
	bmp.chip_version = result >> 8;
}

void reg_check(self){
	write_byte_data(BMP280_REGISTER_SOFTRESET, 0xB6);
	delay(200);
	write_byte_data(BMP280_REGISTER_CONTROL, CTRL_MEAS);
	delay(200);
	write_byte_data(BMP280_REGISTER_CONFIG, CONFIG);
	delay(200);

	dig_T1 = read_word_data_unsigned(BMP280_REGISTER_DIG_T1); // read correction settings
	dig_T2 = read_word_data_signed(BMP280_REGISTER_DIG_T2);
	dig_T3 = read_word_data_signed(BMP280_REGISTER_DIG_T3);
	dig_P1 = read_word_data_unsigned(BMP280_REGISTER_DIG_P1);
	dig_P2 = read_word_data_signed(BMP280_REGISTER_DIG_P2);
	dig_P3 = read_word_data_signed(BMP280_REGISTER_DIG_P3);
	dig_P4 = read_word_data_signed(BMP280_REGISTER_DIG_P4);
	dig_P5 = read_word_data_signed(BMP280_REGISTER_DIG_P5);
	dig_P6 = read_word_data_signed(BMP280_REGISTER_DIG_P6);
	dig_P7 = read_word_data_signed(BMP280_REGISTER_DIG_P7);
	dig_P8 = read_word_data_signed(BMP280_REGISTER_DIG_P8);
	dig_P9 = read_word_data_signed(BMP280_REGISTER_DIG_P9);
}

void read(){
	int raw_temperature_msb, raw_temperature_lsb, raw_temperature_xlsb;
	int raw_pressure_msb, raw_pressure_lsb, raw_pressure_xlsb;
	int raw_temperature;
	int raw_pressure;
	double var1, var2, temperature, t_fine, pressure, altitude;

	raw_temperature_msb = read_byte_data(BMP280_REGISTER_TEMPDATA_MSB); // read raw temperature msb
	raw_temperature_lsb = read_byte_data(BMP280_REGISTER_TEMPDATA_LSB); // read raw temperature lsb
	raw_temperature_xlsb = read_byte_data(BMP280_REGISTER_TEMPDATA_XLSB); // read raw temperature xlsb
	raw_pressure_msb = read_byte_data(BMP280_REGISTER_PRESSDATA_MSB); // read raw pressure msb
	raw_pressure_lsb = read_byte_data(BMP280_REGISTER_PRESSDATA_LSB); // read raw pressure lsb
	raw_pressure_xlsb = read_byte_data(BMP280_REGISTER_PRESSDATA_XLSB); // read raw pressure xlsb

	raw_temperature=(raw_temperature_msb <<12)+(raw_temperature_lsb<<4)+(raw_temperature_xlsb>>4); // combine 3 bytes  msb 12 bits left, lsb 4 bits left, xlsb 4 bits right
	raw_pressure=(raw_pressure_msb <<12)+(raw_pressure_lsb <<4)+(raw_pressure_xlsb >>4); // combine 3 bytes  msb 12 bits left, lsb 4 bits left, xlsb 4 bits right

	var1=(raw_temperature/16384.0-dig_T1/1024.0)*dig_T2; // formula for temperature from datasheet
	var2=(raw_temperature/131072.0-dig_T1/8192.0)*(raw_temperature/131072.0-dig_T1/8192.0)*dig_T3; // formula for temperature from datasheet
	temperature=(var1+var2)/5120.0; // formula for temperature from datasheet
	t_fine=(var1+var2); // need for pressure calculation

	var1=t_fine/2.0-64000.0; // formula for pressure from datasheet
	var2=var1*var1*dig_P6/32768.0; // formula for pressure from datasheet
	var2=var2+var1*dig_P5*2; // formula for pressure from datasheet
	var2=var2/4.0+dig_P4*65536.0; // formula for pressure from datasheet
	var1=(dig_P3*var1*var1/524288.0+dig_P2*var1)/524288.0; // formula for pressure from datasheet
	var1=(1.0+var1/32768.0)*dig_P1; // formula for pressure from datasheet
	pressure=1048576.0-raw_pressure; // formula for pressure from datasheet
	pressure=(pressure-var2/4096.0)*6250.0/var1; // formula for pressure from datasheet
	var1=dig_P9*pressure*pressure/2147483648.0; // formula for pressure from datasheet
	var2=pressure*dig_P8/32768.0; // formula for pressure from datasheet
	pressure=pressure+(var1+var2+dig_P7)/16.0; // formula for pressure from datasheet

	//altitude= 44330.0 * (1.0 - pow(pressure / (QNH*100), (1.0/5.255))); // formula for altitude from airpressure

	bmp.temperature = temperature;
	bmp.pressure = pressure / 100.0;
}

void main(){
	int address = 0x77;
	bmp280 = wiringPiI2CSetup(address);
	while (1){
		read_id();

		if(bmp.chip_id == 88){
			reg_check();
			read();
			printf("Temperature : %2.2f `C\n", bmp.temperature);
			printf("Pressure    : %5.4f mbar\n\n", bmp.pressure);
		}
		else{
			printf("Error\n");
			// Chip ID should be 88
			printf("Chip ID     : %d\n", bmp.chip_id);
			printf("Version     : %d\n", bmp.chip_version);
			delay(1000);
		}
	}
}



------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



sample gtk with label
#include <gtk/gtk.h>

void main(int argc, char *argv[])
{
   gtk_init (&argc, &argv);
   GtkWidget *win = gtk_window_new (GTK_WINDOW_TOPLEVEL);

   gtk_window_set_default_size(GTK_WINDOW(win), 250, 150);

   GtkWidget *lbl = gtk_label_new ("100 C");
   GtkWidget *lbl2 = gtk_label_new ("Bar");

   GtkWidget *tbl = gtk_table_new (1, 2, TRUE);
   gtk_table_attach_defaults (GTK_TABLE (tbl),lbl, 0,1,0,1);
   gtk_table_attach_defaults (GTK_TABLE (tbl),lbl2, 1,2,0,1);
   gtk_container_add (GTK_CONTAINER (win), tbl);

   gtk_widget_show_all (win);

   gtk_main();

}



------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------



problem one { trying replaced the gtk label with bmp280 reading }

#include <stdio.h>
#include <wiringPiI2C.h>
#include <math.h>
#include <gtk/gtk.h>
#include <string.h>
#include <glib.h>
#include <unistd.h>

#define QNH             1020

// Power mode
//#define POWER_MODE    0   // sleep mode
//#define POWER_MODE    1   // forced mode
//#define POWER_MODE    2   // forced mode
#define POWER_MODE      3   // normal mode

// Temperature resolution
//#define OSRS_T    0    // skipped
//#define OSRS_T    1    // 16 Bit
//#define OSRS_T    2    // 17 Bit
//#define OSRS_T    3    // 18 Bit
//#define OSRS_T    4    // 19 Bit
#define OSRS_T      5    // 20 Bit

// Pressure resolution
//#define OSRS_P    0   // pressure measurement skipped
//#define OSRS_P    1   // 16 Bit ultra low power
//#define OSRS_P    2   // 17 Bit low power
//#define OSRS_P    3   // 18 Bit standard resolution
//#define OSRS_P    4   // 19 Bit high resolution
#define OSRS_P      5   // 20 Bit ultra high resolution

// Filter settings
//#define FILTER    0   //
//#define FILTER    1   //
//#define FILTER    2   //
//#define FILTER    3   //
#define FILTER      4   //
//#define FILTER    5   //
//#define FILTER    6   //
//#define FILTER    7   //

// Standby settings
//#define T_SB      0     // 000 0,5ms
//#define T_SB      1     // 001 62.5 ms
//#define T_SB      2     // 010 125 ms
//#define T_SB      3     // 011 250ms
#define T_SB        4     // 100 500ms
//#define T_SB      5     // 101 1000ms
//#define T_SB      6     // 110 2000ms
//#define T_SB      7     // 111 4000ms

#define BMP280_REGISTER_DIG_T1				0x88
#define BMP280_REGISTER_DIG_T2				0x8A
#define BMP280_REGISTER_DIG_T3				0x8C
#define BMP280_REGISTER_DIG_P1				0x8E
#define BMP280_REGISTER_DIG_P2				0x90
#define BMP280_REGISTER_DIG_P3				0x92
#define BMP280_REGISTER_DIG_P4				0x94
#define BMP280_REGISTER_DIG_P5				0x96
#define BMP280_REGISTER_DIG_P6				0x98
#define BMP280_REGISTER_DIG_P7				0x9A
#define BMP280_REGISTER_DIG_P8				0x9C
#define BMP280_REGISTER_DIG_P9				0x9E
#define BMP280_REGISTER_CHIPID				0xD0
#define BMP280_REGISTER_VERSION				0xD1
#define BMP280_REGISTER_SOFTRESET			0xE0
#define BMP280_REGISTER_CONTROL				0xF4
#define BMP280_REGISTER_CONFIG				0xF5
#define BMP280_REGISTER_STATUS				0xF3
#define BMP280_REGISTER_TEMPDATA_MSB		0xFA
#define BMP280_REGISTER_TEMPDATA_LSB		0xFB
#define BMP280_REGISTER_TEMPDATA_XLSB		0xFC
#define BMP280_REGISTER_PRESSDATA_MSB		0xF7
#define BMP280_REGISTER_PRESSDATA_LSB		0xF8
#define BMP280_REGISTER_PRESSDATA_XLSB		0xF9

int CONFIG = (T_SB <<5) + (FILTER <<2); // combine bits for config
int CTRL_MEAS = (OSRS_T <<5) + (OSRS_P <<2) + POWER_MODE; // combine bits for ctrl_meas

int bmp280 = 0;
struct {
	int chip_id;
	int chip_version;
	double temperature;
	double pressure;
	double altitude;
} bmp;

int dig_T1 = 0;
int dig_T2 = 0;
int dig_T3 = 0;
int dig_P1 = 0;
int dig_P2 = 0;
int dig_P3 = 0;
int dig_P4 = 0;
int dig_P5 = 0;
int dig_P6 = 0;
int dig_P7 = 0;
int dig_P8 = 0;
int dig_P9 = 0;

void write_byte_data(int reg, int value){
	wiringPiI2CWriteReg8(bmp280, reg, value);
}

int read_byte_data(int reg){
	int result;
	result = wiringPiI2CReadReg8(bmp280, reg);
	return result;
}

int read_word_data_unsigned(int reg){
	int result;
	result = wiringPiI2CReadReg16(bmp280, reg);
	return result;
}

int read_word_data_signed(int reg){
	int result;
	result = read_word_data_unsigned(reg);
	if (result > 32767){
		result -= 65536;
	}
	return result;
}

void read_id(self){
	int REG_ID     = 0xD0;
	int result;
	result = read_word_data_unsigned(REG_ID);
	bmp.chip_id = result & 0x00FF;
	bmp.chip_version = result >> 8;
}

void reg_check(self){
	write_byte_data(BMP280_REGISTER_SOFTRESET, 0xB6);
	delay(200);
	write_byte_data(BMP280_REGISTER_CONTROL, CTRL_MEAS);
	delay(200);
	write_byte_data(BMP280_REGISTER_CONFIG, CONFIG);
	delay(200);

	dig_T1 = read_word_data_unsigned(BMP280_REGISTER_DIG_T1); // read correction settings
	dig_T2 = read_word_data_signed(BMP280_REGISTER_DIG_T2);
	dig_T3 = read_word_data_signed(BMP280_REGISTER_DIG_T3);
	dig_P1 = read_word_data_unsigned(BMP280_REGISTER_DIG_P1);
	dig_P2 = read_word_data_signed(BMP280_REGISTER_DIG_P2);
	dig_P3 = read_word_data_signed(BMP280_REGISTER_DIG_P3);
	dig_P4 = read_word_data_signed(BMP280_REGISTER_DIG_P4);
	dig_P5 = read_word_data_signed(BMP280_REGISTER_DIG_P5);
	dig_P6 = read_word_data_signed(BMP280_REGISTER_DIG_P6);
	dig_P7 = read_word_data_signed(BMP280_REGISTER_DIG_P7);
	dig_P8 = read_word_data_signed(BMP280_REGISTER_DIG_P8);
	dig_P9 = read_word_data_signed(BMP280_REGISTER_DIG_P9);
}

void read(){
	int raw_temperature_msb, raw_temperature_lsb, raw_temperature_xlsb;
	int raw_pressure_msb, raw_pressure_lsb, raw_pressure_xlsb;
	int raw_temperature;
	int raw_pressure;
	double var1, var2, temperature, t_fine, pressure, altitude;

	raw_temperature_msb = read_byte_data(BMP280_REGISTER_TEMPDATA_MSB); // read raw temperature msb
	raw_temperature_lsb = read_byte_data(BMP280_REGISTER_TEMPDATA_LSB); // read raw temperature lsb
	raw_temperature_xlsb = read_byte_data(BMP280_REGISTER_TEMPDATA_XLSB); // read raw temperature xlsb
	raw_pressure_msb = read_byte_data(BMP280_REGISTER_PRESSDATA_MSB); // read raw pressure msb
	raw_pressure_lsb = read_byte_data(BMP280_REGISTER_PRESSDATA_LSB); // read raw pressure lsb
	raw_pressure_xlsb = read_byte_data(BMP280_REGISTER_PRESSDATA_XLSB); // read raw pressure xlsb

	raw_temperature=(raw_temperature_msb <<12)+(raw_temperature_lsb<<4)+(raw_temperature_xlsb>>4); // combine 3 bytes  msb 12 bits left, lsb 4 bits left, xlsb 4 bits right
	raw_pressure=(raw_pressure_msb <<12)+(raw_pressure_lsb <<4)+(raw_pressure_xlsb >>4); // combine 3 bytes  msb 12 bits left, lsb 4 bits left, xlsb 4 bits right

	var1=(raw_temperature/16384.0-dig_T1/1024.0)*dig_T2; // formula for temperature from datasheet
	var2=(raw_temperature/131072.0-dig_T1/8192.0)*(raw_temperature/131072.0-dig_T1/8192.0)*dig_T3; // formula for temperature from datasheet
	temperature=(var1+var2)/5120.0; // formula for temperature from datasheet
	t_fine=(var1+var2); // need for pressure calculation

	var1=t_fine/2.0-64000.0; // formula for pressure from datasheet
	var2=var1*var1*dig_P6/32768.0; // formula for pressure from datasheet
	var2=var2+var1*dig_P5*2; // formula for pressure from datasheet
	var2=var2/4.0+dig_P4*65536.0; // formula for pressure from datasheet
	var1=(dig_P3*var1*var1/524288.0+dig_P2*var1)/524288.0; // formula for pressure from datasheet
	var1=(1.0+var1/32768.0)*dig_P1; // formula for pressure from datasheet
	pressure=1048576.0-raw_pressure; // formula for pressure from datasheet
	pressure=(pressure-var2/4096.0)*6250.0/var1; // formula for pressure from datasheet
	var1=dig_P9*pressure*pressure/2147483648.0; // formula for pressure from datasheet
	var2=pressure*dig_P8/32768.0; // formula for pressure from datasheet
	pressure=pressure+(var1+var2+dig_P7)/16.0; // formula for pressure from datasheet

	//altitude= 44330.0 * (1.0 - pow(pressure / (QNH*100), (1.0/5.255))); // formula for altitude from airpressure

	bmp.temperature = temperature;
	bmp.pressure = pressure / 100.0;

}

 int main(){
	int address = 0x77;
	bmp280 = wiringPiI2CSetup(address);
	while (1){
		read_id();
		char Sta[100];
		char Stb[100];
		if(bmp.chip_id == 88){
			reg_check();
			read();
			
			// printf("Temperature : %2.2f `C\n", bmp.temperature);
			// printf("Pressure    : %5.4f mbar\n\n", bmp.pressure);
			sprintf(Sta, "Temperature : %2.2f `C\n", bmp.temperature);
			sprintf(Stb, "Pressure    : %5.4f mbar\n\n", bmp.pressure);

		

		}
		else{
			printf("Error\n");
			// Chip ID should be 88
			// printf("Chip ID     : %d\n", bmp.chip_id);
			// printf("Version     : %d\n", bmp.chip_version);
			sprintf(Sta, "Chip ID     : %d\n", bmp.chip_id);
			sprintf(Stb, "Version     : %d\n", bmp.chip_version);
			delay(1000);
		}
		


	 int gtk(int argc, char *argv[])
   	{ 


   	gtk_init (&argc, &argv);
   	GtkWidget *win = gtk_window_new (GTK_WINDOW_TOPLEVEL);

	   gtk_window_set_default_size(GTK_WINDOW(win), 250, 150);

	   GtkWidget *lbl = gtk_label_new (Sta);
	   GtkWidget *lbl2 = gtk_label_new (Stb);

	   GtkWidget *tbl = gtk_table_new (1, 2, TRUE);
	   gtk_table_attach_defaults (GTK_TABLE (tbl),lbl, 0,1,0,1);
	   gtk_table_attach_defaults (GTK_TABLE (tbl),lbl2, 1,2,0,1);
	   gtk_container_add (GTK_CONTAINER (win), tbl);

	   gtk_widget_show_all (win);

	   gtk_main();

	  }
     }
}


What I have tried:

i might a starter for c Programming, but i had given a task to make a gui of bmp280 sensor. Actually i haven't learn any programming before, suddenly i had transfer to programming part and i had to make the GUI about sensor reading. i want to get solution as fast as possible.
Posted
Updated 16-Mar-20 21:32pm
v4
Comments
Richard MacCutchan 16-Mar-20 7:57am
   
It is no good just dumping all your code and saying, "I got some problem". We have no way of guessing what problem you are referring to or where it occurs. So, please, once again, Only show the code that is relevant to the problem, and explain clearly what the problem is, and where it occurs. And that includes the exact text of any error messages.
markkuk 16-Mar-20 8:43am
   
Cutting and pasting random bits of code together will never work. You need to actually read and learn the basics to create a working program.
KarstenK 16-Mar-20 9:07am
   
show the problematic code line and the FULL error text message. Maybe you can google after the error code yourself ...
boonC 17-Mar-20 3:34am
   
even you say google, google cannot help so much. google cannot give you any related solution. if the google have solution, i won't had write a forum get some advise or help from others.

1 solution

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Solution 1

Quote:
void read(){
int raw_temperature_msb, raw_temperature_lsb, raw_temperature_xlsb;
int raw_pressure_msb, raw_pressure_lsb, raw_pressure_xlsb;
int raw_temperature;
That's the culprit.
Your function name conflicts with this one: read(2) - Linux manual page[^].
I suggest you to change your function signature to something like:
void read_all_values()
   

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