[SOLVED] measuring 2 different source of voltages using 1 ADC.. how?

Code C - [expand]
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#include <REG51.H>
#define adc_port P3
#define adc_out P2
 
sbit ale=P1^0;  //address latch enable
sbit oe=P1^3;  //output enable
sbit sc=P1^1;  //start conversion
sbit eoc=P1^2;  //end of conversion
sbit clk=P1^7;  // clock
 
sbit ADD_A=P1^4;  // Address pins for selecting input channels.
sbit ADD_B=P1^5;
sbit ADD_C=P1^6;
 
 
 
void timer0() interrupt 1  // Function to generate clock of frequency 500KHZ using Timer 0 interrupt.
{
clk=~clk;
}
 
void delay(unsigned int count)  // Function to provide time delay in msec.
{
int i,j;
for(i=0;i<count;i++)
  for(j=0;j<1275;j++);
}
 
 
void select_channel(char c,char b,char a)
{
  ADD_A = a;
  ADD_B = b;
  ADD_C = c;
}
 
 
 
void convert()
{
  delay(1);
  ale=0;      //activate the ale PIN
  delay(1);
  ale=1;
  sc=1;      //initaite convertion
  delay(1);
  sc=0;
  delay(1);
 
 
 
 
}
void read_adc()
{
   while(eoc == 0);  //end of convertion
   oe = 1;           //enable adc output
   delay(2);
   oe = 0;
 
}
 
 
void main()
{
 
  P2 = 0x00;
  
  TMOD =  0x22;  //timer0 setting for generating clock of 500KHz using interrupt enable mode.
  TH0  =  0xFD;
  IE   =  0x82;
  TR0  =  1;
 
 while(1)
 {
   select_channel(0,0,1);
   convert();
   read_adc();
 
}
}

Code C++ - [expand]
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void timer0() interrupt 1  // Function to generate clock of frequency 500KHZ using Timer 0 interrupt.
{
clk=~clk; // output clock pulse to p1.7
}
 
 
void main()
{
 TMOD =  0x22;  //timer0 setting for generating clock of 500KHz using interrupt enable mode.
  TH0  =  0xFD;
  IE   =  0x82;
  TR0  =  1;
  while(1);
}

Code C - [expand]
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// Lcd module connections
sbit LCD_RS at P2_0_bit;
sbit LCD_EN at P2_1_bit;
sbit LCD_D4 at P2_2_bit;
sbit LCD_D5 at P2_3_bit;
sbit LCD_D6 at P2_4_bit;
sbit LCD_D7 at P2_5_bit;
// End Lcd module connections
 
 
sbit charging at P2_6_bit;
sbit full at P2_7_bit;
sbit control at P0_7_bit;
 
 
float inputa, inputb;
//adc config
sbit ale at P1_0_bit;  //address latch enable
sbit oe  at P1_3_bit;  //output enable
sbit sc  at P1_1_bit;  //start conversion
sbit eoc at P1_2_bit;  //end of conversion
sbit clk at P1_7_bit;  // clock
 
sbit ADD_A  at P1_4_bit;  // Address pins for selecting input channels.
sbit ADD_B  at P1_5_bit;
sbit ADD_C  at P1_6_bit;
 
 
 
void select_channel(char c,char b,char a)
{
  ADD_A = a;
  ADD_B = b;
  ADD_C = c;
}
 
void convert()
{
  ale=1;
  Delay_ms(5);
  sc=1;
  Delay_ms(10);
  sc=0;
  Delay_ms(1);
  ale=0;
}
 
 
void read_adc()
{
  while(eoc==0);
  oe=1;
  Delay_ms(1);
}
 
void get_adc(char x)
{
 
  select_channel(0,0,x);
  convert();
  read_adc();
  read_adc();
 
  if(x==0)
  inputa = P3;
  else if(x==1)
  inputb = P3;
 
}
 
 
void Timer1InterruptHandler() org IVT_ADDR_ET1
{
  clk = ~clk;
}
 
 
 
void main()
{
  float volt_a,volt_b;
  char txt[15];
  char txt2[15];
  char x;
  
  full = 0;
  charging = 0;
  control = 0;
  
  ET1_bit = 1;       // Enable Timer1 interrupt
  EA_bit  = 1;       // Set global interrupt enable
  GATE1_bit = 0;     // Clear this flag to enable Timer1 whenever TR1 bit is set.
  C_T1_bit  = 0;     // Set Timer operation: Timer1 counts the divided-down systam clock.
  
  TR1_bit = 0;       // Turn off Timer1
  TMOD = 0x22;
  TH1 = 0x00;        // Set Timer1 high byte
  TL1 = 0x00;        // Set Timer1 low byte
 
  TR1_bit = 1;       // Run Timer1
  
  
  Lcd_Init();                        // Initialize Lcd
  Lcd_Cmd(_LCD_CURSOR_OFF);          // Cursor off
  Lcd_Cmd(_LCD_CLEAR);               // Clear display
  while(1)
  {
 
 
      get_adc(0);
      Delay_ms(90);
      get_adc(1);
      x++;
      if(x==20)
      {
        Lcd_Cmd(_LCD_CLEAR);
        x=0;
 
      }
   //for windmill volatage display
      volt_a = (( inputa * 5) / 255)* 4;
      
      if(inputa<=10)
      volt_a = 0;
 
      FloatToStr(volt_a,txt);
      Lcd_Out(1,1,"Wind:");
      Lcd_Out(1,16,"V");
      Lcd_Out(1,7,txt);
 
     //for battery display
      //inputb=164;
      volt_b = (( inputb * 5) / 255)* 4;
      
      if(inputb<=10)
      volt_b = 0;
      else if(inputb >= 164) //165 = 12.8v which is battery full
      {
        full =1;
        control = 1;
      }
      else if(inputb >= 152)  //152 = 11.92v which is battery is discharge
      {
        charging = 1;
        full = 0;
      }
      //IntToStr(inputb,txt2);
 
      FloatToStr(volt_b,txt2);
      Lcd_Out(2,1,"Batt:");
      Lcd_Out(2,16,"V");
      Lcd_Out(2,7,txt2);
 
 
 
 
 
 
 
 
  }
}