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finitespace / BME280

Provides an Arduino library for reading and interpreting Bosch BME280 data over I2C, SPI or Sw SPI.
GNU General Public License v3.0
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Lowest power mode possible #96

Closed leestephens closed 5 years ago

leestephens commented 6 years ago

Expected behavior

Looking in the Datasheet, I think there is a mode (as described in 3.5.1) that does 1 sample per minute.

I assume this would be expressed in BME280.h setting enum StandbyTime as StandbyTime_60000ms

Actual behavior

StandbyTime_1000ms is the largest value

Request

Am I misunderstanding the way of using the code? Or can this be added? I actually only want to read the values every 10 minutes, so looking to get the lowest power possible. Maybe I might be better turning the device into Mode_Sleep and then switching to Mode_Forced when I want to take a reading?

BTW, thank you for an excellent library, very grateful for all the work involved.

gartfr commented 6 years ago

From the same doc, the table that shows register config for standby time in forced mode is the following : t_sb[2:0] tstandby [ms] 000 0.5 001 62.5 010 125 011 250 100 500 101 1000 110 10 111 20

so the longest standby time is 1000ms and no other. In 3.5.1, they're I can see what you mean : Data output rate : 1/60 Hz I think it's more an advice on how to use the chip but not a specific mode to configure the chip.

I agree with you, if using a 10 min sample rate, I would use the sleep mode.

regards,

coelner commented 5 years ago

@leestephens gartfr answer is correct. the sensor can only sleep for 1000ms therefore use (as suggested) the forced mode. Could you close the issue?

leestephens commented 5 years ago

Thanks once again.