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rotaryio: shared_module_softencoder_state_update: no need for BAD state

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All we do on a BAD state transition is avoid counting up or down,
but the same is accomplished by using the "0" table value instead.
This commit is contained in:
Jeff Epler 2021-10-15 11:24:39 -05:00
parent 23d2c96476
commit a0dd2ccec1
1 changed files with 4 additions and 9 deletions
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13
shared-module/rotaryio/IncrementalEncoder.c
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@ -35,21 +35,20 @@ void shared_module_softencoder_state_init(rotaryio_incrementalencoder_obj_t *sel
}
void shared_module_softencoder_state_update(rotaryio_incrementalencoder_obj_t *self, uint8_t new_state) {
#define BAD 7
static const int8_t transitions[16] = {
0, // 00 -> 00 no movement
-1, // 00 -> 01 3/4 ccw (11 detent) or 1/4 ccw (00 at detent)
+1, // 00 -> 10 3/4 cw or 1/4 cw
BAD, // 00 -> 11 non-Gray-code transition
0, // 00 -> 11 non-Gray-code transition
+1, // 01 -> 00 2/4 or 4/4 cw
0, // 01 -> 01 no movement
BAD, // 01 -> 10 non-Gray-code transition
0, // 01 -> 10 non-Gray-code transition
-1, // 01 -> 11 4/4 or 2/4 ccw
-1, // 10 -> 00 2/4 or 4/4 ccw
BAD, // 10 -> 01 non-Gray-code transition
0, // 10 -> 01 non-Gray-code transition
0, // 10 -> 10 no movement
+1, // 10 -> 11 4/4 or 2/4 cw
BAD, // 11 -> 00 non-Gray-code transition
0, // 11 -> 00 non-Gray-code transition
+1, // 11 -> 01 1/4 or 3/4 cw
-1, // 11 -> 10 1/4 or 3/4 ccw
0, // 11 -> 11 no movement
@ -60,10 +59,6 @@ void shared_module_softencoder_state_update(rotaryio_incrementalencoder_obj_t *s
self->state = new_state;
int8_t quarter_incr = transitions[idx];
if (quarter_incr == BAD) {
// Missed a transition. We don't know which way we're going, so do nothing.
return;
}
self->quarter_count += quarter_incr;