zhouhang shao
/
test
test
encoder.cpp@6:9f698d1b2996, 2017-05-13 (annotated)
- Committer:
- kolanery
- Date:
- Sat May 13 19:42:23 2017 +0000
- Revision:
- 6:9f698d1b2996
- Parent:
- 3:34a763e93423
update test case
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
kolanery | 6:9f698d1b2996 | 1 | /* |
szh66 | 3:34a763e93423 | 2 | #include "encoder.h" |
kolanery | 6:9f698d1b2996 | 3 | |
kolanery | 6:9f698d1b2996 | 4 | |
szh66 | 3:34a763e93423 | 5 | void resetEncoders(){ |
szh66 | 3:34a763e93423 | 6 | leftEncoder.reset(); |
szh66 | 3:34a763e93423 | 7 | } |
szh66 | 3:34a763e93423 | 8 | |
szh66 | 3:34a763e93423 | 9 | int getEncoderDistance(){ |
szh66 | 3:34a763e93423 | 10 | return (leftEncoder) >> 1; |
szh66 | 3:34a763e93423 | 11 | } |
szh66 | 3:34a763e93423 | 12 | |
szh66 | 3:34a763e93423 | 13 | Encoder::Encoder(PinName channelA, PinName channelB) : |
szh66 | 3:34a763e93423 | 14 | channelA_(channelA), |
szh66 | 3:34a763e93423 | 15 | channelB_(channelB){ |
szh66 | 3:34a763e93423 | 16 | pulses = 0; |
szh66 | 3:34a763e93423 | 17 | |
szh66 | 3:34a763e93423 | 18 | //Workout what the current state is. |
szh66 | 3:34a763e93423 | 19 | int chanA = channelA_.read(); |
szh66 | 3:34a763e93423 | 20 | int chanB = channelB_.read(); |
szh66 | 3:34a763e93423 | 21 | |
szh66 | 3:34a763e93423 | 22 | //2-bit state. |
szh66 | 3:34a763e93423 | 23 | currState_ = (chanA << 1) | (chanB); |
szh66 | 3:34a763e93423 | 24 | prevState_ = currState_; |
szh66 | 3:34a763e93423 | 25 | |
szh66 | 3:34a763e93423 | 26 | channelA_.rise(this, &Encoder::encode); |
szh66 | 3:34a763e93423 | 27 | channelA_.fall(this, &Encoder::encode); |
szh66 | 3:34a763e93423 | 28 | } |
szh66 | 3:34a763e93423 | 29 | |
szh66 | 3:34a763e93423 | 30 | //Internally updates the pulse count for the encoder. |
szh66 | 3:34a763e93423 | 31 | void Encoder::encode(void) { |
szh66 | 3:34a763e93423 | 32 | int chanA = channelA_.read(); |
szh66 | 3:34a763e93423 | 33 | int chanB = channelB_.read(); |
szh66 | 3:34a763e93423 | 34 | |
szh66 | 3:34a763e93423 | 35 | //2-bit state. |
szh66 | 3:34a763e93423 | 36 | currState_ = (chanA << 1) | (chanB); |
szh66 | 3:34a763e93423 | 37 | |
szh66 | 3:34a763e93423 | 38 | //11->00->11->00 is counter clockwise rotation or "forward". |
szh66 | 3:34a763e93423 | 39 | if ((prevState_ == 0x3 && currState_ == 0x0) || |
szh66 | 3:34a763e93423 | 40 | (prevState_ == 0x0 && currState_ == 0x3)) { |
szh66 | 3:34a763e93423 | 41 | pulses+=2; |
szh66 | 3:34a763e93423 | 42 | } |
szh66 | 3:34a763e93423 | 43 | //10->01->10->01 is clockwise rotation or "backward". |
szh66 | 3:34a763e93423 | 44 | else if ((prevState_ == 0x2 && currState_ == 0x1) || |
szh66 | 3:34a763e93423 | 45 | (prevState_ == 0x1 && currState_ == 0x2)) { |
szh66 | 3:34a763e93423 | 46 | pulses-=2; |
szh66 | 3:34a763e93423 | 47 | } |
szh66 | 3:34a763e93423 | 48 | |
szh66 | 3:34a763e93423 | 49 | prevState_ = currState_; |
szh66 | 3:34a763e93423 | 50 | } |
szh66 | 3:34a763e93423 | 51 | |
szh66 | 3:34a763e93423 | 52 | //Resets the encoder |
szh66 | 3:34a763e93423 | 53 | void Encoder::reset(void) { |
szh66 | 3:34a763e93423 | 54 | pulses = 0; |
kolanery | 6:9f698d1b2996 | 55 | }*/ |