Custom pwm input range/travel in MultiWii

I use MultiWii for my quadcopter. But I had a problem. My transmitter was not able to send values in the full range (1000-2000), so i had to scale the value from the center point (1500) up, and down.

Replace the fraction 22/20 with whatever scaling value you want, and replace THROTTLEPIN with whatever pin you want to scale.

Here are the changes I made (RX.ino in MultiWii 2.2):

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@@ -110,8 +114,13 @@
rcValue[rc_value_pos] = dTime; \
if((rc_value_pos==THROTTLEPIN || rc_value_pos==YAWPIN || \
rc_value_pos==PITCHPIN || rc_value_pos==ROLLPIN) \
- && dTime>FAILSAFE_DETECT_TRESHOLD) \
- GoodPulses |= (1<<rc_value_pos); \
+ && dTime>FAILSAFE_DETECT_TRESHOLD) { \
+ GoodPulses |= (1<<rc_value_pos); \
+ if (rc_value_pos == THROTTLEPIN) { \
+ tmp = ((int16_t)dTime-1500)*22/20+1500; \
+ rcValue[rc_value_pos] = tmp; \
+ } \
+ } \
} \
} else edgeTime[pin_pos] = cTime; \
}
@@ -133,6 +142,7 @@
uint8_t mask;
uint8_t pin;
uint16_t cTime,dTime;
+ int16_t tmp;
static uint16_t edgeTime[8];
static uint8_t PCintLast;
#if defined(FAILSAFE) && !defined(PROMICRO)