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main.cpp@0:17b00659dfd2, 2015-10-06 (annotated)
- Committer:
- margotr
- Date:
- Tue Oct 06 14:55:51 2015 +0000
- Revision:
- 0:17b00659dfd2
Simple biquad;
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| margotr | 0:17b00659dfd2 | 1 | |
| margotr | 0:17b00659dfd2 | 2 | #include "mbed.h" |
| margotr | 0:17b00659dfd2 | 3 | #include "HIDScope.h" |
| margotr | 0:17b00659dfd2 | 4 | |
| margotr | 0:17b00659dfd2 | 5 | |
| margotr | 0:17b00659dfd2 | 6 | Serial pc(USBTX, USBRX); |
| margotr | 0:17b00659dfd2 | 7 | |
| margotr | 0:17b00659dfd2 | 8 | HIDScope scope(1); |
| margotr | 0:17b00659dfd2 | 9 | Ticker scopeTimer; |
| margotr | 0:17b00659dfd2 | 10 | |
| margotr | 0:17b00659dfd2 | 11 | // Read the analog input |
| margotr | 0:17b00659dfd2 | 12 | AnalogIn ain(A0); |
| margotr | 0:17b00659dfd2 | 13 | |
| margotr | 0:17b00659dfd2 | 14 | const double a1=-1.993955222010733; |
| margotr | 0:17b00659dfd2 | 15 | const double a2=0.9939734363649758; |
| margotr | 0:17b00659dfd2 | 16 | const double b0=0.9969821645939272; |
| margotr | 0:17b00659dfd2 | 17 | const double b1=-1.9939643291878544; |
| margotr | 0:17b00659dfd2 | 18 | const double b2=0.9969821645939272; |
| margotr | 0:17b00659dfd2 | 19 | |
| margotr | 0:17b00659dfd2 | 20 | |
| margotr | 0:17b00659dfd2 | 21 | double v1, v2; |
| margotr | 0:17b00659dfd2 | 22 | |
| margotr | 0:17b00659dfd2 | 23 | |
| margotr | 0:17b00659dfd2 | 24 | |
| margotr | 0:17b00659dfd2 | 25 | double biquadFilter() { |
| margotr | 0:17b00659dfd2 | 26 | |
| margotr | 0:17b00659dfd2 | 27 | double v = ain.read() - a1*v1 - a2*v2; |
| margotr | 0:17b00659dfd2 | 28 | double y = b0*v + b1*v1 + b2*v2; |
| margotr | 0:17b00659dfd2 | 29 | v2 = v1; |
| margotr | 0:17b00659dfd2 | 30 | v1 = v; |
| margotr | 0:17b00659dfd2 | 31 | return y; |
| margotr | 0:17b00659dfd2 | 32 | |
| margotr | 0:17b00659dfd2 | 33 | }; |
| margotr | 0:17b00659dfd2 | 34 | |
| margotr | 0:17b00659dfd2 | 35 | void scopeSend() |
| margotr | 0:17b00659dfd2 | 36 | { |
| margotr | 0:17b00659dfd2 | 37 | scope.set(0,ain); |
| margotr | 0:17b00659dfd2 | 38 | scope.send(); |
| margotr | 0:17b00659dfd2 | 39 | |
| margotr | 0:17b00659dfd2 | 40 | } |
| margotr | 0:17b00659dfd2 | 41 | |
| margotr | 0:17b00659dfd2 | 42 | int main() |
| margotr | 0:17b00659dfd2 | 43 | { |
| margotr | 0:17b00659dfd2 | 44 | |
| margotr | 0:17b00659dfd2 | 45 | // Attach the data read and send function at 100 Hz |
| margotr | 0:17b00659dfd2 | 46 | scopeTimer.attach_us(&scopeSend, 1e4); |
| margotr | 0:17b00659dfd2 | 47 | pc.printf("foo!\n"); |
| margotr | 0:17b00659dfd2 | 48 | |
| margotr | 0:17b00659dfd2 | 49 | while(1) { } |
| margotr | 0:17b00659dfd2 | 50 | } |