PID programming for MSP430, need advice.

[l1n0x]

Dear all members
I'm about to program a PID code for the msp430. I already programmed the Analog-to-digital convert, so all i need is the last pid part.
Since both "timers" on the PID i reserved for other items. I have another idea on how to solve the problem, but i'm totally lost.

The adc stores 3 values from the temperature sensor. I want the PID to compare those 3 values with out set point. And if it's not equal, do the P-regulation..
If the actual point don't reach the set point within 3 times, i want the PI-regulation..
The system should always compare to the latest value from the ADC.
How am i suppose to program this in C?
Please any advice will be appriciatet.
Thanks in advance

 

[kender]

Here's a classical EETimes article **broken link removed**. You'll find it useful.

 

[bbgil]

Here is a PID program used for LEGO Robotics. You can follow the PID programiing guide using the Pseudo codes. Hope this helps. The pseudo codes have been used for other projects involving microcontrollers like the PID controller temperature controller etc.