As AVR2560 is not supported anymore and do integer operations is
usually faster than float-point the _calculate() implementation was
done using only integer operations and as more close to what
datasheet says.
If there is a read error, reading from the adc will return 0 but moreover,
we need to re-initiate a read or else we are stuck forever.
From MS5611-01BA03 datasheet, p. 10, CONVERSION SEQUENCE:
"After the conversion, using ADC read command the result is clocked out with the MSB first.
If the conversion is not executed before the ADC read command, or the ADC read command is
repeated, it will give 0 as the output result."
If we have an error in the SPI or I2C transaction we should not change
the state. Otherwise we might read a temperature when the sensor is
reporting pressure and vice-versa.
This param seems to have been un-implemented. This is putting it back in. Adds a meter offset to the calculated altitude form the baro sensors.
Also changes it from int8 to float
This commit changes the way libraries headers are included in source files:
- If the header is in the same directory the source belongs to, so the
notation '#include ""' is used with the path relative to the directory
containing the source.
- If the header is outside the directory containing the source, then we use
the notation '#include <>' with the path relative to libraries folder.
Some of the advantages of such approach:
- Only one search path for libraries headers.
- OSs like Windows may have a better lookup time.
this allows the use of an external temperature sensor for calibration
purposes, such as the sensor built in to the digital airspeed sensor.
The main affect this has is on the EAS2TAS calculation
The get_calibration_temperature() is used to choose either an external
temperature or an internal one. If an internal one is used then it is
clamped at no higher than 25 degrees C, to prevent hot electronics
on startup affecting altitude scaling and EAS2TAS
