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how to dispaly the a/d value from PIC16F877 using visual basic in digital value

Sat, 16 Feb 2008 00:41:05 -0800

hi i'm a newbie in this one. can anyone help me with this? i'm using miKroC for programming the microcontroller. now i want to display the readings of the micocontroller in visual basic. for example i have a voltage output 4v read by the ucontroller and want to display the digital output in visual basic... thank you very much for sparing your time...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 01 Mar 2008 22:24:05 -0800

help needed urgently... why the code for my microcontroller wont detect a voltage? the leds don't turn on when i put 3vs as an analog input. everyone help me? and then the vb code for displaying the reading...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sun, 17 Feb 2008 10:10:10 -0800

@Norms
Can you explain your project in some detail(mainly the algo)....
As for the C program some things look suspect.....

CODE:

norms = (( 2.5 *1023)/5);

Now why would you do that?Why not simply 'norms=511',which is the value you get from that computation.
And what is 'volts_out'?Are you reading in some value from the serial port?

CODE:

else if(volts_out==get_adc)

You haven't initialised get_adc,so you're in effect comparing volts_out to garbage.

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 01:01:55 -0800

send the value to PC using UART and then display it in VB software after reading from COM port. All you need to do is COM port programming in Visual Basic (search forum for more information)

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 01:21:45 -0800

this is my c program for microcontroller... any help or suggestion? it doestn have an error though

CODE:

unsigned int volts_out;
unsigned int get_adc;
unsigned int x;
unsigned int norms;
unsigned int value;
unsigned int temp1;
unsigned int temp2;

void main()
{
 int exit = 1;
 Usart_Init(9600);
 ADCON0 = 0x80;
 ADCON1 = 0x80;
 ADCON0.ADON = 1; // Enables A/D Conversion
 TRISB = 0;
 PORTB = 0;
 RCSTA = 0x90;
 TXSTA = 0x24;
 Delay_ms(100);
 
 for(;;)
  {
    if(Usart_Data_Ready())
    {
      exit=1;
      PORTB=0;
      volts_out=Usart_Read();
      Delay_ms(100);
      norms = (( 2.5 *1023)/5);
      if(volts_out==norms)  // Within the 240-220 voltage range
      {
       x = volts_out * (5/1023);
        do
        {
          PORTB.F2=1;
          PORTB.F3=1;
          PORTB.F4=1;
          PORTB.F5=1;
          Delay_ms(100);
          if(Usart_Data_Ready())
          {
            exit=0;
          }
        } while(exit);
      }
      else if(volts_out>norms) // Greater than 240 Volts
      {
        x = volts_out * (5/1023);
        do
        {
            PORTB.F2=1;
            PORTB.F3=0;
            PORTB.F4=0;
            PORTB.F5=1;
            Delay_ms(100);
            if(Usart_Data_Ready())
          {
            exit=0;
          }
        } while(exit);
      }
      else if(volts_out)
      {
        x = volts_out * (5/1023);
        do
        {
          PORTB.F2=0;
          PORTB.F3=1;
          PORTB.F4=1;
          PORTB.F5=0;
          Delay_ms(100);
          if(Usart_Data_Ready())
          {
            exit=0;
          }
        }
        while(exit);
      }
      else if(volts_out==get_adc)
      {
        do
        {
          ADRESH=0;
          ADRESL=0;
          PORTB.F1=1;
          ADCON0.GO=1;
          Delay_ms(100);
          value=Adc_Read(0);
          Delay_ms(100);
          exit=0;
          temp1=ADRESH;
          temp2=ADRESL;
          Delay_ms(100);
          PORTB.F1=0;
          Delay_ms(100);
          Eeprom_Write(0,temp1);
          Delay_ms(20);
          Eeprom_Write(1,temp2);
          Delay_ms(20);
          Delay_ms(50);
          Usart_Write(Eeprom_Read(0));
          Delay_ms(20);
          Usart_Write(Eeprom_Read(1));
          Delay_ms(50);
          if(Usart_Data_Ready())
          {
            exit=0;
          }
        } while(exit);
      }
    }
    else
    {
      PORTB=0xff;
    }
  }
 
}
 

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 01:23:04 -0800

how i am going to display the read value in visual basic in digital form?

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 04:20:21 -0800

how actually you are displaying your ADC output and where?

also what do you mean by digital form? can you explain with example?

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 06:16:09 -0800

the x = .... is the one i will be calling in the visual basic...
i mean decimal value, sorry...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 06:48:55 -0800

consider you have value=56 in microcontroller...now convert decimal to a string. and send seriially to vb.
it that wat you want

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 09:31:35 -0800

Do you mean something like this:

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 08:37:29 -0800

abbas1707 wrote ...

consider you have value=56 in microcontroller...now convert decimal to a string. and send seriially to vb.
it that wat you want

yup...

this is how i am going to convert

2.5v is the output read from a certain load then i'll convert it to decimal like this:

norms = (( 2.5 *1023)/5);

then ill have this declaration:

if (volts_out==norms)

//ill convert the decimal to a voltage value

x = (volts_out * (5))/1023 // this is the voltage that ill be calling to the visual basic program, am i right?

in vb

the value of x will be multiply to the ratio of the transformer like this

y = (x*220)/5

so y is the final value that i will like to be display in vb...

so is it ok?

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 10:10:27 -0800

yup but the voltage vill be converted to 220v from 8.7 for example. so insted of 8.7v in display it will now display 220V

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 22:25:06 -0800

GioppY wrote ...

Hi.
I have attached the vb6 source code and the exe.
It communicate by one of the available com port on your pc @ 2400 baud,n,8,1
It wait for a string in the following format xx,xCR (CR means carriage return) where xx,x is a numeric value in the 00,0 to 19,9 range (please note the comma).
When receive the string it display the value (the string as received) and plot a graphic representation; after 128 samples the plot is erased and restarted.
It wait for a string every second; i do not know if it can handle higher sample rate.
Obviously you have to modify the code for your requirement.
Regards
Gianni
P.S.
220v ??? I hope that you use a transformer to REDUCE and ISOLATE the mains from the pic and from the pc
batt_mon.zip

Gioppy can you check my c program for microcontroller if its correct? thanks

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 10:14:10 -0800

GioppY wrote ...

Do you mean something like this:

can you teach mo how? like to ask for your code on that... please

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 11:27:42 -0800

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sat, 16 Feb 2008 11:39:47 -0800

thanks... yup i am using a transformer to step down the voltage then have some declarations equating 220=2.5 volts... thank you very much...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sun, 17 Feb 2008 07:56:04 -0800

Sorry! I do not know C language. I use picbasic.
Regards

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 18 Feb 2008 01:14:00 -0800

volts_out is the value read from the output of the load... its not from the serial port... hehehe, i just want to show the computation so any man know how i get the 511 value... so is the program ok?

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 18 Feb 2008 09:24:35 -0800

Except for get_adc value rest seems ok.
btw what is the get_adc for?

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Tue, 19 Feb 2008 02:24:48 -0800

its for getting the reading from the load... like the decimal value and as well as the digital value...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Thu, 21 Feb 2008 22:56:55 -0800

heres my vb code: please and kindly check it. thanks

CODE:

Private Sub CmdExit_Click()
    If MSComm1.PortOpen = True Then
    MSComm1.PortOpen = False
    End If
        End
End Sub
Private Sub Form_Load()
    MSComm1.InputLen = 0
    MSComm1.CommPort = 1
    MSComm1.Settings = "2400,N,8,1"
End Sub
Private Sub Timer1_Timer()
    Dim BytesToRead As Integer
    Dim norms As Variant
    MSComm1.PortOpen = True
    BytesToRead = 1
    Do
        DoEvents
        Loop Until MSComm1.InBufferCount = BytesToRead
        norms = MSComm1.Input
        Text1.Text = (((Asc(norms) * 0.01) * 230) / 2.5) & " Volts AC"
        MSComm1.PortOpen = False
End Sub
 

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sun, 02 Mar 2008 06:35:03 -0800

i need to see the circuit atleast..

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sun, 02 Mar 2008 12:04:22 -0800

On close examination of your code,this is the logic I figured out.....

for(;;)
{
if(usart receive buffer is full)...read usart....volts_out=value read
{ if(volts_out=511)....light up some leds and loop till receive buffer is full again
elseif(volts_out<511)....light up some leds and loop till receive buffer is full again
elseif(volts_out>511)....light up some leds and loop till receive buffer is full again
elseif(volts_out=get_adc)...read adc value,store it in EEPROM,read the stored
EEPROM value and send it to USART
}
else...PORTB=0xFF
}

Instead of the ADC you are reading in the value "Volts_out" from the USART....why?
Moreover you need to send in some value from the PC to the USART in order for the 1st ' if' statement to trigger.(if(usart receive buffer is full))
And then the variable get_adc...you are comparing volts_out to it before providing it with an initial value(you've only declared it "unsigned int get_adc;",not initialised it).

Look at the code below...this is how it should be.

unsigned int adc_val;
unsigned char volts_out;

void main()
{
USART_Init(9600);
ADCON1 = 0x80;
TRISA = 0xFF; // PORTA is input
TRISB = 0; // PORTB is output
PORTB = 0;

while (1)
{
adc_val = ADC_Read(2);
volts_out = adc_val * 5/1023;
USART_Write(volts_out);
if(adc_val==511)
{PORTB = 0xFF;}
else if(adc_val<511)
{PORTB = 0x0F;}
else
{PORTB = 0xF0;}
Delay_ms(5000);
}

}

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sun, 02 Mar 2008 23:48:48 -0800

my vb code... please check and correct it... thank you very much guys...

Private Sub CmdExit_Click()
If MSComm1.PortOpen = True Then
MSComm1.PortOpen = False
End If
End
End Sub
Private Sub Form_Load()
MSComm1.InputLen = 0
MSComm1.CommPort = 1
MSComm1.Settings = "2400,N,8,1"
End Sub
Private Sub Timer1_Timer()
Dim BytesToRead As Integer
Dim adc As Variant
MSComm1.PortOpen = True
BytesToRead = 1
Do
DoEvents
Loop Until MSComm1.InBufferCount = BytesToRead
adc = MSComm1.Input
Text1.Text = (((Asc(adc) * 0.01) * 230) / 2.5) & " Volts AC"
MSComm1.PortOpen = False
End Sub

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Sun, 02 Mar 2008 23:46:55 -0800

at this moment my current code for my microcontroller 16F877, please correct it and write the code if you don't mind... please... really reallly need it.

void main()
{
int limit = 512;
int vout;
int adc;
int x;
int value;
int temp1;
int temp2;
int exit = 1;

Usart_Init(2400);
ADCON0 = 0x80;
ADCON1 = 0x80;
ADCON0.ADON = 1; // Enables A/D Conversion
TRISB = 0;
PORTB = 0;
RCSTA = 0x90;
TXSTA = 0x24;
Delay_ms(100);

for(;;)
{
if(Usart_Data_Ready())
{
exit=1;
PORTB=0;
vout=Usart_Read();
Delay_ms(100);

if(vout == 512) // Within the 240 Voltage Range, equal to 2.5 volts
{
do
{
PORTB.F1 = 1;
PORTB.F2 = 1;
PORTB.F3 = 1;
PORTB.F4 = 1;
PORTB.F5 = 1;
PORTB.F6 = 1;
PORTB.F7 = 1;
Delay_ms(1000);
if(Usart_Data_Ready())
{
exit=0;
}
}
while(exit);
}
else if(vout > 512) // Greater than 240 Volts, greater than 2.5 volts
{
do
{
PORTB.F1 = 1;
PORTB.F3 = 1;
PORTB.F5 = 1;
PORTB.F7 = 1;
Delay_ms(1000);
if(Usart_Data_Ready())
{
exit=0;
}
}
while(exit);
}
else if (vout < 512) // Less than 240 volts, less than 2.5 volts
{
do
{
PORTB.F2 = 0;
PORTB.F4 = 0;
PORTB.F6 = 0;
Delay_ms(1000);
if (Usart_Data_Ready())
{
exit = 0;
}
}
while(exit);
}
else if (vout == 0)
{
do
{
PORTB.F1=0;
PORTB.F2=0;
PORTB.F3=0;
PORTB.F4=0;
PORTB.F5=0;
PORTB.F6=0;
PORTB.F7=0;
if(Usart_Data_Ready())
{
exit=0;
}
}
while(exit);
}
else if(vout == adc)
{
do
{
ADRESH=0;
ADRESL=0;
ADCON0.GO=1;
Delay_ms(100);
value=Adc_Read(0);
Delay_ms(100);
exit=0;
temp1=ADRESH;
temp2=ADRESL;
Delay_ms(1000);
Eeprom_Write(0,temp1);
Delay_ms(20);
Eeprom_Write(1,temp2);
Delay_ms(70);
Usart_Write(Eeprom_Read(0));
Delay_ms(20);
Usart_Write(Eeprom_Read(1));
Delay_ms(50);
if(Usart_Data_Ready())
{
exit=0;
}
}
while(exit);
}
}
else
{
PORTB=0xff;
}
}
}

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 03 Mar 2008 00:09:18 -0800

this is my circuit

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 03 Mar 2008 00:32:06 -0800

the Tx and Rx were put incorrectly... Rx should in the Tx place...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 03 Mar 2008 23:35:55 -0800

sashijoseph wrote ...

Like I pointed out ealier your PIC code won't work.For eg.

CODE:

if(Usart_Data_Ready())

why are you checking the (PIC's) serial port input buffer?Are you sending sth into the PIC's serial port?If not then why use this check?

Then you have

CODE:

vout=Usart_Read();

You should be getting the value from the ADC rather than the serial port.

Similarly there are plenty of flaws.......

Look at the code below.This is all you need to read in ADC value and send it as two bytes to the PC's serial port.

unsigned int adc_val;
unsigned char low_byte,hi_byte;
void main()
{
USART_Init(9600);
ADCON1 = 0;
TRISA = 0xFF; // PORTA is input
TRISB = 0; // PORTB is output
PORTB = 0;

while (1)
{
adc_val = ADC_Read(2); //get ADC value
low_byte = adc_val; //split the 2-byte integer into 2 separate bytes
hi_byte = adc_val >> 8; //for sending to pc serial port
USART_Write(low_byte); //send the 1st (lower) byte
USART_Write(hi_byte); //send the upper byte
if(adc_val==511) //if ADC value read in is 511
{PORTB = 0xFF;} //display some LED's on PORTB
else if(adc_val<511)
{PORTB = 0x0F;}
else
{PORTB = 0xF0;}
Delay_ms(5000); //gather a sample after 5 secs.
}
}

what happened to the USART_Write(volts_out)? in your first correction you have it, then now its gone, replace by the low and high byte... please enlightened me with this...

then in my vb pro, do i need to change the BytesToRead = 1 to 2? and then the "adc=MSComm1.Input"
what will be my input here? thanks

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Tue, 04 Mar 2008 09:18:12 -0800

heres my code and its working, i can light the leds now..... hope you can add the necessary codes for transmitting the signal to the serial port... pls help...

void main()
{
int limit=512;
int value;
TRISA=0xff; // Configure PORTA as analog input
TRISB=0; // Configure PORTB as output
PORTA=0;
PORTB=0;
ADCON0=0b10000000;
ADCON1=0b10001110;
ADCON0.ADON=1; // Enable ADC
for(;;)
{
ADCON0.GO=1;
Delay_us(10);
value=Adc_Read(0);
if(value>=512) // value is greater or equal to 2.5V
{
PORTB.F0=1;
PORTB.F2=1;
PORTB.F4=1;
PORTB.F6=1;
Delay_ms(100);
PORTB.F0=0;
PORTB.F2=0;
PORTB.F4=0;
PORTB.F6=0;
Delay_ms(100);
}
else if(value<512)
{
PORTB.F1=1;
PORTB.F3=1;
PORTB.F5=1;
PORTB.F7=1;
Delay_ms(100);
PORTB.F1=0;
PORTB.F3=0;
PORTB.F5=0;
PORTB.F7=0;
Delay_ms(100);
}
Delay_ms(3000);
}
}

and pls help me in my vb program... here is my first vb program...

Private Sub CmdExit_Click()
If MSComm1.PortOpen = True Then
MSComm1.PortOpen = False
End If
End
End Sub
Private Sub Form_Load()
MSComm1.InputLen = 0
MSComm1.CommPort = 1
MSComm1.Settings = "9600,N,8,1"
End Sub
Private Sub Timer1_Timer()
Dim BytesToRead As Integer
Dim value As Variant
MSComm1.PortOpen = True
BytesToRead = 1
Do
DoEvents
Loop Until MSComm1.InBufferCount = BytesToRead
value = MSComm1.Input
Text1.Text = (((Asc(value) * 0.01) * 230) / 2.5) & " Volts AC"
MSComm1.PortOpen = False
End Sub

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 03 Mar 2008 23:11:16 -0800

thanks sashijoseph for the help. appreciate it very much... ill test it tonight ill keep in touchwith you. you save my life...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Mon, 03 Mar 2008 11:17:40 -0800

Like I pointed out ealier your PIC code won't work.For eg.

CODE:

if(Usart_Data_Ready())

why are you checking the (PIC's) serial port input buffer?Are you sending sth into the PIC's serial port?If not then why use this check?

Then you have

CODE:

vout=Usart_Read();

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Tue, 04 Mar 2008 00:00:26 -0800

The previous USART_Write(volts_out) would send out the value volts_out which had been declared as char hence only rounded off values(ie1,2,3,4,5) would be sent instead of say 1.87 or 2.54 etc.It was only for checking proper working.
The actual value received by the adc,which is an integer (2bytes) is split into two bytes and sent to the PC as Low_byte and Hi_byte.In the PC you can then 'join' the 2 bytes to the original int and then convert it to the appropriate voltage reading to be displayed. Hope it's clear.
I would suggest doing things step by step.First program the PIC and see if the LED's are working correctly.Then use Hyperterminal and check if the serial code is OK.Finally make the VB program.

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Tue, 04 Mar 2008 01:37:39 -0800

thanks.. ill try it tonight...

Re: how to dispaly the a/d value from PIC16F877 using visual basic in digital value

contact@nospam.com (Ajay Bhargav) — Tue, 04 Mar 2008 07:24:22 -0800

hmm im trying it right now, and it can't light the leds on... does something in my circuit is wrong? the schematic diagram of my pic was posted before here. kindly check it sashjoseph, ive changed the ADCON1 to ADCON0, so the input will be put in AN0 in pin number 2, am i right?