Revision 0c80370b
Added struct filter_state, so we can filter multiple signals
| arduino/RadioBuggyMega/filter.c | ||
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#include "receiver.h" |
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#include "filter.h" |
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// This only does preliminary initialization. |
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// More initialization is done in the function body. |
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void filter_init(struct filter_state *state) {
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state->started = 0; |
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} |
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#define SIZE 5 // the array size |
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static char started = 0; |
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static int last_val_sent; |
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static int values[5]; |
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static int pos; |
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int filter(int val){
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int filter_loop(struct filter_state *state, int val){
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int i; |
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// First initialization: on assumption val is never -1 |
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if(!started){
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for(i = 0; i < SIZE; i++){
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values[i] = val; |
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if(!(state->started)){
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for(i = 0; i < FILTER_LEN; i++){
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state->prev_values[i] = val;
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} |
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pos = 0; // initialize the positions of the next number to be changed |
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started = 1; |
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state->pos = 0; // initialize the positions of the next number to be changed
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state->started = 1;
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return val; |
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} |
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// NOT first initialization. |
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values[pos] = val; // replace the number in the array
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pos = (pos+1)%SIZE; // increment the pos number
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state->prev_values[state->pos] = val; // replace the number in the array
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state->pos = (state->pos+1)%FILTER_LEN;// increment the pos number
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// calculate average of array |
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int sum = 0; |
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for(i = 0; i < SIZE; i++){
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sum += values[i]; |
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for(i = 0; i < FILTER_LEN; i++){
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sum += state->prev_values[i];
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} |
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int avg = sum/SIZE;
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int avg = sum/FILTER_LEN;
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// return. |
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return avg; |
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} |
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} |
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