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Code Issues Wiki Activity

fix dshot_600

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This commit is contained in:
Thorsten Laux 2019-09-07 07:31:34 +02:00
parent db66284567
commit f9da3ea755
2 changed files with 52 additions and 46 deletions
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51
src/main/drivers/dshot_bitbang_decode.c
View file

@ -129,14 +129,17 @@ uint32_t decode_bb_bitband( uint16_t buffer[], uint32_t count, uint32_t bit)
#endif #endif
while (endP > p) { while (endP > p) {
while (endP > p) { do {
// Look for next positive edge. Manual loop unrolling and branch hinting to produce faster code. // Look for next positive edge. Manual loop unrolling and branch hinting to produce faster code.
if(__builtin_expect(!(p++)->value, 1) && if(__builtin_expect((p++)->value, 0) ||
__builtin_expect(!(p++)->value, 1) && __builtin_expect((p++)->value, 0) ||
__builtin_expect(!(p++)->value, 1) && __builtin_expect((p++)->value, 0) ||
__builtin_expect(!(p++)->value, 1)) { __builtin_expect((p++)->value, 0)) {
continue; break;
} }
} while (endP > p);
if (endP > p) {
#ifdef DEBUG_BBDECODE #ifdef DEBUG_BBDECODE
sequence[sequenceIndex++] = p - b; sequence[sequenceIndex++] = p - b;
@ -149,17 +152,19 @@ uint32_t decode_bb_bitband( uint16_t buffer[], uint32_t count, uint32_t bit)
value <<= len; value <<= len;
value |= 1 << (len - 1); value |= 1 << (len - 1);
oldP = p; oldP = p;
break;
}
// Look for next zero edge. Manual loop unrolling and branch hinting to produce faster code. // Look for next zero edge. Manual loop unrolling and branch hinting to produce faster code.
while (endP > p) { do {
if (__builtin_expect((p++)->value, 1) && if (__builtin_expect(!(p++)->value, 0) ||
__builtin_expect((p++)->value, 1) && __builtin_expect(!(p++)->value, 0) ||
__builtin_expect((p++)->value, 1) && __builtin_expect(!(p++)->value, 0) ||
__builtin_expect((p++)->value, 1)) { __builtin_expect(!(p++)->value, 0)) {
continue; break;
} }
} while (endP > p);
if (endP > p) {
#ifdef DEBUG_BBDECODE #ifdef DEBUG_BBDECODE
sequence[sequenceIndex++] = p - b; sequence[sequenceIndex++] = p - b;
#endif #endif
@ -171,7 +176,7 @@ uint32_t decode_bb_bitband( uint16_t buffer[], uint32_t count, uint32_t bit)
value <<= len; value <<= len;
value |= 1 << (len - 1); value |= 1 << (len - 1);
oldP = p; oldP = p;
break; }
} }
} }
@ -243,15 +248,13 @@ FAST_CODE uint32_t decode_bb( uint16_t buffer[], uint32_t count, uint32_t bit)
sequence[sequenceIndex++] = p - buffer; sequence[sequenceIndex++] = p - buffer;
#endif #endif
while (endP > p ) {
// Look for next edge. Manual loop unrolling and branch hinting to produce faster code. // Look for next edge. Manual loop unrolling and branch hinting to produce faster code.
while (endP > p) { if (__builtin_expect((*p++ & mask) != lastValue, 0) ||
if (__builtin_expect((*p++ & mask) == lastValue, 1) && __builtin_expect((*p++ & mask) != lastValue, 0) ||
__builtin_expect((*p++ & mask) == lastValue, 1) && __builtin_expect((*p++ & mask) != lastValue, 0) ||
__builtin_expect((*p++ & mask) == lastValue, 1) && __builtin_expect((*p++ & mask) != lastValue, 0)) {
__builtin_expect((*p++ & mask) == lastValue, 1)) { if (endP > p) {
continue;
}
#ifdef DEBUG_BBDECODE #ifdef DEBUG_BBDECODE
sequence[sequenceIndex++] = p - buffer; sequence[sequenceIndex++] = p - buffer;
#endif #endif
@ -265,6 +268,8 @@ FAST_CODE uint32_t decode_bb( uint16_t buffer[], uint32_t count, uint32_t bit)
oldP = p; oldP = p;
lastValue = *(p-1) & mask; lastValue = *(p-1) & mask;
} }
}
}
// length of last sequence has to be inferred since the last bit with inverted dshot is high // length of last sequence has to be inferred since the last bit with inverted dshot is high
if (bits < 18) { if (bits < 18) {

3
src/main/drivers/dshot_bitbang_impl.h
View file

@ -199,7 +199,8 @@ extern uint32_t bbOutputBuffer[MOTOR_DSHOT_BUFFER_SIZE * MAX_SUPPORTED_MOTOR_POR
// <sampling period> = 0.44us // <sampling period> = 0.44us
// <slack> = 10% // <slack> = 10%
// (30 + 26 + 3) / 0.44 = 134 // (30 + 26 + 3) / 0.44 = 134
#define DSHOT_BITBANG_PORT_INPUT_BUFFER_LENGTH 134 // In some cases this was not enough, so we add 6 extra samples
#define DSHOT_BITBANG_PORT_INPUT_BUFFER_LENGTH 140
extern uint16_t bbInputBuffer[DSHOT_BITBANG_PORT_INPUT_BUFFER_LENGTH * MAX_SUPPORTED_MOTOR_PORTS]; extern uint16_t bbInputBuffer[DSHOT_BITBANG_PORT_INPUT_BUFFER_LENGTH * MAX_SUPPORTED_MOTOR_PORTS];
void bbGpioSetup(bbMotor_t *bbMotor); void bbGpioSetup(bbMotor_t *bbMotor);