Hello,
I'm looking for the best choice to implement fast PID controllers
using limited computational resources. The performance of these
controllers need not be the optimal, but reasonable and off course, it
should allow easy tuning to stabllity.

As i understand the I_PARAMETER term is usually created by applying the P_PARAMETER to a LP filter. In my case this is too costly in terms of computational power, it is much more easy to apply the P_PARAMETER into a FIFO buffer and calculate the average value of all the records inside this FIFO for each PID Control Tick/

Is this approach may supply reasonable result?

The same question about the D_PARAMETER.... if i will just subtract the current P_PARAMETER value with an older one taken from the same FIFO buffer?

As i understand the I_PARAMETER term is usually created by applying the P_PARAMETER to a LP filter. In my case this is too costly in terms of computational power, it is much more easy to apply the P_PARAMETER into a FIFO buffer and calculate the average value of all the records inside this FIFO for each PID Control Tick/

Is this approach may supply reasonable result?

The same question about the D_PARAMETER.... if i will just subtract the current P_PARAMETER value with an older one taken from the same FIFO buffer?