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Date: Fri, 16 Feb 2024 21:35:16 +0100
From: Dimitri Fedrau <dima.fedrau@gmail.com>
To: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>,
	Lars-Peter Clausen <lars@metafoo.de>, Nuno Sa <nuno.sa@analog.com>,
	Li peiyu <579lpy@gmail.com>, linux-iio@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4 3/3] iio: humidity: hdc3020: add threshold events
 support
Message-ID: <20240216203516.GA3873@debian>
References: <20240214085350.19382-1-dima.fedrau@gmail.com>
 <20240214085350.19382-4-dima.fedrau@gmail.com>
 <b159b10b-513f-4116-b2ef-faf6741dc3b6@gmail.com>
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Am Thu, Feb 15, 2024 at 12:18:41AM +0100 schrieb Javier Carrasco:
> On 14.02.24 09:53, Dimitri Fedrau wrote:
> > Add threshold events support for temperature and relative humidity. To
> > enable them the higher and lower threshold registers must be programmed
> > and the higher threshold must be greater then or equal to the lower
> > threshold. Otherwise the event is disabled. Invalid hysteresis values
> > are ignored by the device. There is no further configuration possible.
> > 
> > Tested by setting thresholds/hysteresis and turning the heater on/off.
> > Used iio_event_monitor in tools/iio to catch events while constantly
> > displaying temperature and humidity values.
> > 
> > Signed-off-by: Dimitri Fedrau <dima.fedrau@gmail.com>
> > ---
> 
> Hi Dimitri,
>
Hi Javier,

> now that the decimal part is used, the resolution loss is within the
> ranges mentioned in the datasheet.
> 
> For the records: the truncated values lead to alerts slightly lower than
> the target alerts. Therefore, measured values below the "comfort zone"
> defined by the user (but close to the low alert) will not trigger
> events. The other way around is "more secure" because the target comfort
> zone is guaranteed:
> 
> -------- High val -> event (as expected)
> 
> ******** Target High Alert
> 
> -------- Meas -> **event** (still in target comfort zone)
> 
> ######## Truncated High Alert
> 
> ...
> 
> ******** Target Low Alert
> 
> -------- Meas -> **no event** (out of target comfort zone)
> 
> ######## Truncated Low Alert
> 
> -------- Meas -> event (as expected)
> 
> But as I said, the resolution loss is in the valid range anyway:
> 
> Tested-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
> 
> Thank you for adding this feature.
>
thanks for testing.

Best regards,
Dimitri Fedrau