Code in C for PID temperature controller

[ritula.thakur]

pid c code

I want to develop a 8051 based PID temeperature controller.i will be using IC temperture sensor LM35DZ .
Please send me the code in C for the same on my mail id ritula.thakur@gmail.com.
Writing code in C is not my cup of tea.Im gud in developing hardware but when softwware comes i get panicky.so please please help me. I any one has the full code please mail it to me as soon as possible. i shall e highly obliged
Thanks in advance

 

[ritula.thakur]

pid control c code

To be moore precise abt my project. The temp sensor LM35DZ will be sensing the actual temperature of process and this temp will be converted into digital form by ADC 0809 and sent to microcontroller.The user can set the desired temp through keyboard.There is also LCD interfacing which will display the actual tempertaure and set temp.Th eprogram in C will containg PID algorithm to operate a relay which is connected to heater and thus accordingly turn it ON and OFF.

 

[oscar_pdx]

pid control code

Simple PID

PID = GainP * actual error + GainI * SUM(previous errors) + GainD * (actual error - last error)

error = sp(set point) - pv(process value)


float pid (float sp, float pv)
{

err_old = err;
err = sp - pv;

// note
P_err = err;
I_err += err_old;
D_err = err - err_old;

return 0.1*P_err + 0.3*I_err + 0.02*D_err;

}


//note. Dead zone example: if (err<2 && err>-2){err=0;}

 

[asifrehmat]

pid controller c code

Good explanation oscar_pdx.

 

[funnynypd]

pid code in c

That's a float-point version.

 

[Fernando Vasquez]

c code pid

/*u=kp*(e+Td*diff(e)+Td*int(e))
y0=analog input 1;
r0=ref=set point or reference;
T=sample time;
qd=diff constant=Kp*Td/T; //Td:diff time
qi=integral cosntant=Kp*T/Ti; //Ti:Integration time
Kp=prop gain;*/

float pid (float r0, float y0)
{
e0=r0-y0;
D=qd*(e0-e1);
if (((u>umin)|(e>0))&((u<umax)|(e<0))) //antiwindup integral
I=I+qi*(r0-y0);

u=Kp*e0+D+I;//pid control signal
if (u>umax) u=umax; //antiwindup PID
if (u<umin) u=umin;

e1=e0; //save old values
y1=y0;
}

 

[SmartBomb1979]

simple pid c code

if (((u>umin)|(e>0))&((u<umax)|(e<0))) //antiwindup integral

Your code should use the || and && operators. I put in bold the problem areas.

& and | are binary bitwise operators and not logical operators.

 

[kender]

simple pid code

Here's a link to an article **broken link removed** it has some ANSI C code. It's not complete, but it might still be helpful.

 

[kapilddit]

This all code ref is not working properly....
I want to inplement full controlled pid...
How can i do that please help me out in this...

Thanks...

kapilddit...