problem measure humidity using hs1101

[Osawa_Odessa]

Hello, could anyone help me with the circuit and program bellow.
I want to use HS1101 to measure humidity using 16F877A in CCS. Here is the circuit I have built as in datasheet of HS1101.

Is the circuit look OK to you? I think it is ok but I am not sure if there is something wrong with it.
And here is the program I have used to measure humidity:

#include "main.h"
#include "var.h"
#include "lcd16x2/lcd16x2.c"
#include "hs1101/hs1101.c"
#INT_RTCC
void  ngat_timer0(void) 
{
   disable_interrupts(GLOBAL);
   set_timer0(5);
   count++;
   if(count==100)
   {
      frequency=get_timer1();
      set_timer1(0);
      count=0;
      enable_display=1;
   }
   enable_interrupts(GLOBAL);   
}

void main()
{
   uint8_t str[20],humi;
   DDRB=0xfe;
   DDRD=0x00;
   DDRE=0x00;
   LCD_Init();
   setup_timer_1(T1_EXTERNAL|T1_DIV_BY_1);
   setup_timer_0(RTCC_INTERNAL|RTCC_DIV_256|RTCC_8_BIT);  
   sprintf(str,"Test");
   LCD_Puts(str);
   delay_ms(40);
   set_timer0(5);
   set_timer1(0);
   enable_interrupts(INT_TIMER0);   
   enable_interrupts(GLOBAL);
 while(TRUE)
   {
 
     if(enable_display)
     {
         
     humi=HS1101_GetHumi(frequency);
     enable_display=0;
     sprintf(str,"Do Am:%3u",humi);
     LCD_Gotoxy(0,1);
     LCD_Puts(str);
     LCD_PutChar('%');
     }
   }
}

And here is hs1101.c

/**
  ******************************************************************************
  * Ten Tep      :        hs1101.c
  * Tac Gia      :        Nguyen Quy Nhat
  * Cong Ty      :        MinhHaGroup
  * Website      :        BanLinhKien.Vn
  * Phien Ban    :        V1.0.0
  * Ngay         :        31-07-2012
  * Tom Tat      :        Dinh nghia ham do do am HS1101, khai bao bang tra.
  *           
  *
  ******************************************************************************
  * Chu Y        :                   
  ******************************************************************************
**/
#include "hs1101.h"
const uint16_t HS1101_Table[101]={
                         8109,8090,8070,8051,8033,8015,7997,7979,7961,7944,
                         7927,7910,7894,7878,7862,7846,7830,7815,7799,7784, 
                         7769,7755,7740,7726,7711,7697,7683,7669,7655,7641,
                         7628,7614,7600,7587,7574,7560,7547,7534,7521,7507,
                         7494,7481,7468,7455,7442,7429,7416,7403,7390,7377,
                         7364,7350,7337,7324,7311,7298,7284,7271,7257,7244,
                         7230,7216,7203,7189,7175,7161,7147,7132,7118,7103,
                         7089,7074,7059,7045,7029,7014,6999,6984,6968,6952,
                         6936,6920,6904,6888,6872,6855,6838,6821,6804,6787,
                         6770,6752,6735,6717,6699,6680,6662,6644,6625,6606,
                         6587};
/*******************************************************************************
Noi Dung    :   Doc gia tri do am.
Tham Bien   :   frequency: tan so do duoc tu bo dao dong NE555 ket hop HS1101.
Tra Ve      :   Gia tri do am do duoc tu HS1101.
********************************************************************************/
uint8_t HS1101_GetHumi(uint16_t frequency)
{
   uint8_t i;
   for(i=0;i<101;i++)
   {
      if((frequency+25)>HS1101_Table[i])return i;
   }
   return 100;
}
/******************************KET THUC FILE******************************
______________________________NGUYEN QUY NHAT______________________________*/

I have tried to changed the cap-var to change frequency and therefore change humidity but it always display humidity 0%.
Could you tell me what I am wrong? Your help is greatly appreciated!

 

[jayanth.devarayanadurga]

I will answer in another 1 hour. Mention your Compiler, MCU, Fosc.

 

[Osawa_Odessa]

Hello,
Thanks, I use picc compiler CCS, pic 16F877A and Fosc = 20 Mhz.:smile:
I will attach some file in case you need to see it in more detail

- - - Updated - - -

I have checked by replace output of 555(in this case is Fout) by pulse generator in proteus. I changed its frequency and check if humidity is displayed correct but it is not. Sometimes it is correct but most of the cases it is entirely wrong. I have checked code many times both main.c and hs1101.c but I don't see what is wrong with it.

 

[jayanth.devarayanadurga]

Check this https://www.qsl.net/ve3lny/humidity.html I will check your code and reply.

 

[Osawa_Odessa]

Hello,
Now this code is work well when I use pulse generator to create frequency and connect to PIC.

#include "main.h"
#include "var.h"
#include "lcd16x2/lcd16x2.c"
#include "hs1101/hs1101.c"
#INT_RTCC
void  ngat_timer0(void) 
{
   disable_interrupts(GLOBAL);
   set_timer0(5);
   count++;
   if(count==78)
   {
      frequency=get_timer1();
      set_timer1(0);
      count=0;
      enable_display=1;
   }
   enable_interrupts(GLOBAL);   
}

void main()
{
   uint8_t str[20],humi;
   //DDRB=0xfe;
   DDRD=0x00;
   DDRE=0x00;
   LCD_Init();
   setup_timer_1(T1_EXTERNAL|T1_DIV_BY_1);
   setup_timer_0(RTCC_INTERNAL|RTCC_DIV_256|RTCC_8_BIT);  
   set_timer0(6);
   set_timer1(0);
   enable_interrupts(INT_TIMER0);   
   enable_interrupts(GLOBAL); 
   sprintf(str,"BanLinhKien.Vn");
   LCD_Puts(str);
   //delay_us(10);
   while(TRUE)
   {
  if(enable_display)
     {
    
    humi=HS1101_GetHumi(frequency);
     enable_display=0;
    sprintf(str,"Do Am:%3u",humi);
     LCD_Gotoxy(0,1);
     LCD_Puts(str);
     LCD_PutChar('%');
     }
   }
}

But when I connect the output Fout from NE5555 it doesn't work. I think the problem here is from the circuit. I made it as in datasheet but I think I need to know how it work.

- - - Updated - - -

Aha, it works now!:-D I change nothing! I don't know why but the only problem now is that the time for LCD to display the humidity is too slow. I think it may be 10s delay.