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Fix underflow in channel based RSSI calculations for out of range values

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If the RSSI channel PWM values were outside the expected 1000-2000 range, the `scaleRange()` function does not work properly. In particular if the value was below the minimum the result would be negative. Then this would cause an underflow when applied as a `uint16` to `setRssiDirect()`. This fix constrains the input range from 1000 to 2000.
This commit is contained in:
Bruce Luckcuck 2020-08-14 18:59:47 -04:00
parent 77ceda89c4
commit cd4d756790
1 changed files with 1 additions and 1 deletions
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2
src/main/rx/rx.c
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@ -757,7 +757,7 @@ static void updateRSSIPWM(void)
int16_t pwmRssi = rcData[rxConfig()->rssi_channel - 1];
// Range of rawPwmRssi is [1000;2000]. rssi should be in [0;1023];
setRssiDirect(scaleRange(pwmRssi, PWM_RANGE_MIN, PWM_RANGE_MAX, 0, RSSI_MAX_VALUE), RSSI_SOURCE_RX_CHANNEL);
setRssiDirect(scaleRange(constrain(pwmRssi, PWM_RANGE_MIN, PWM_RANGE_MAX), PWM_RANGE_MIN, PWM_RANGE_MAX, 0, RSSI_MAX_VALUE), RSSI_SOURCE_RX_CHANNEL);
}
static void updateRSSIADC(timeUs_t currentTimeUs)