mohsin152
Newbie level 1
Hi every one,
I am new to pic and have recently started to study its basics.I am making a simple project of displaying temperature via LM35. I am having a problem with displaying values of ADC conversion on lcd with PIC 18F458. i am using floatTostr to convert values into character stings. But when i try to display, if the value is greater than 1 (such as 1.2) it gets displayed correctly but for values less than 1 such as .5 it is displayed as 5 which means it gets multiplied by 10 automatically and even if the value to be displayed is .005 still lcd shows 5. My code is following
I am new to pic and have recently started to study its basics.I am making a simple project of displaying temperature via LM35. I am having a problem with displaying values of ADC conversion on lcd with PIC 18F458. i am using floatTostr to convert values into character stings. But when i try to display, if the value is greater than 1 (such as 1.2) it gets displayed correctly but for values less than 1 such as .5 it is displayed as 5 which means it gets multiplied by 10 automatically and even if the value to be displayed is .005 still lcd shows 5. My code is following
Code:
// LCD module connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D7 at RB0_bit;
sbit LCD_D6 at RB1_bit;
sbit LCD_D5 at RB2_bit;
sbit LCD_D4 at RB3_bit;
sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_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
char temp[] = "Temp(C')"; // to be displayed on lcd
void main()
{
float x=0;
unsigned char temparray[5];
TRISA.F1=1; // make RA1 an input pin for ADC analog signal
ADC_Init();
Lcd_Init(); // Initialize LCD
Lcd_Cmd(_LCD_CLEAR); // Clear display
Lcd_Cmd(_LCD_CURSOR_OFF); // Cursor off
Lcd_Out(1,1,temp); // Write text in first row
while (1)
{
ADCON0=0X81;
ADCON1=0X84; // right justified result,vref+=VDD,vref-=VSS
Delay_ms(20);
x= ADC_Read(1); // temperature sensor output connected at AN1
x=(x*4.89)/1000; // 4.89mV is the step size
floatTostr (x,temparray);
Lcd_Out(1,12,temparray);
}
}
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