Problem with sprintf when convert float to a string

[ngodinhnhan]

Hi all,
I am currently using MikroC PRO for dsPIC v.7.1.0 for dsPIC30F4013 chip.
I want to convert a float number into a string, then display on a LCD. Here is my code:
[double result;
result = 35154239.81;
sprintf(txt3,"%.2Lf",result);
Lcd_Out(2,1,txt3);][/code]

A problem is that my LCD always display as 35154240.00 instead of 35154239.81;

I think there might some settings in MikroC software that effect on the function sprintf.

Any one please help me to fix this error ?

Many thanks in advanced.

Here are my full code:

[// Lcd module connections
sbit LCD_RS at LATD0_bit;
sbit LCD_EN at LATD1_bit;
sbit LCD_D4 at LATB0_bit;
sbit LCD_D5 at LATB1_bit;
sbit LCD_D6 at LATB2_bit;
sbit LCD_D7 at LATB3_bit;

sbit LCD_RS_Direction at TRISD0_bit;
sbit LCD_EN_Direction at TRISD1_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;
// End Lcd module connections

#define INT2_pin LATD9_bit

double result;
char txt3[20]="";

void INT2_Init()
{
INT2_dir = 1; // INT2 direction
INT2_pin = 0; // INT2 direction
IPC5 = 0x1000; // Interrupt is priority 1
INT2EP_bit = 1; // 1 = Interrupt on negative edge; 0 = Interrupt on positive edge
INT2IE_bit = 1;
}
void main() {

ADPCFG = 0xFFFF; // Configure AN pins as digital I/O

INT2_Init();

Delay_ms(1000);
Lcd_Cmd(_LCD_CLEAR);
Lcd_Out(1,1,"2023/02/23");
Delay_ms(1000);
while(1)
{}
}
// Interrupt routine
void External_Interrupt_2() iv IVT_ADDR_INT2INTERRUPT ics ICS_AUTO
{
result = 35154239.81;
sprintf(txt3,"%Lf",result);
Lcd_Cmd(_LCD_CLEAR);
Lcd_Out(2,1,txt3);

INT2IF_bit = 0;
}][/code]

[steve42lawson]

Try removing the 'L' from the format specification:

Code: Select all

sprintf(txt3,"%.2f",result);

The 'L' is only specified for integer types:

The optional characters l or L may immediately precede conversion_type to respectively specify long versions of the integer types d, i, u, o, x, and X.

[ngodinhnhan]

Hi
I was trying to remove "L" character but unfortunately, i still got same error.