Memory of a filter used on real time digital signal processing My question is regarding the memory of a filter when we want to implement it on a real time dsp environment. We have certain memories like scratch memory , intermediate memory and internal memory. Does anyone knows how to we implement a filter in real time environment keeping in mind the memory considerations because memory is an important issue when it comes to real time signal processing. I want to implement a low pass filter using the above conditions.
If memory is your primary concern then an IIR filter is the way to go.  It uses very little memory and is pretty computationally efficient.

FIR filters' memory length is one less than the number of filter taps.  This usually isn't that much, but it can add up if there are a number of filters and/or they are long.