avsa242/aht20-spin

Parallax P8X32A/Propeller, P2X8C4M64P/Propeller 2 driver object for the ASAIR AHT20 Temp/RH sensor

aht20-spin

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This is a P8X32A/Propeller, P2X8C4M64P/Propeller 2 driver object for the ASAIR AHT20 Temperature/RH sensor

IMPORTANT: This software is meant to be used with the spin-standard-library (P8X32A) or p2-spin-standard-library (P2X8C4M64P). Please install the applicable library first before attempting to use this code, otherwise you will be missing several files required to build the project.

Salient Features

• I2C connection at up to 400kHz
• Read temperature, relative humidity (current and previous measurements)
• Measurements are validated by CRC

Requirements

P1/SPIN1:

• spin-standard-library
• sensor.temp_rh.common.spinh (provided by spin-standard-library)
• 1 extra core/cog for the PASM-based I2C engine (none if bytecode-based engine is used)

P2/SPIN2:

• p2-spin-standard-library
• sensor.temp_rh.common.spin2h (provided by p2-spin-standard-library)

Compiler Compatibility

Processor	Language	Compiler	Backend	Status
P1	SPIN1	FlexSpin (6.5.0-beta)	Bytecode	OK
P1	SPIN1	FlexSpin (6.5.0-beta)	Native code	OK
P2	SPIN2	FlexSpin (6.5.0-beta)	NuCode	OK
P2	SPIN2	FlexSpin (6.5.0-beta)	Native code	OK

(other versions or toolchains not listed are not supported, and may or may not work)

Limitations

• TBD

aht20-spin's Issues

driver start hangs

Sometimes the driver never returns from startx() - the call to dev_id() (which in turn calls i2c.present()) doesn't return in all situations.