FlashAir-SlibBME280

Lua library for BME280 environmental sensor for FlashAir.

Tested equipment

Tested on this GY-BME280 module with BME280 and FlashAir W-04 v4.00.03.

FlashAir to BME280 module connections

GY-BME280 has 10korm pull-up register for SCL, SDA, CSB.
And it has 10korm pull-down register for SD0.
So, register is not necessary.

GY-BME280 module	FlashAir(Pin#)	Power	Memo
SD0	CLK (5)		CLK pull-down in module
SCL	CMD (2)		SCL pull-up in module
SDA	DAT0(7)		SDA pull-up in module
---	DAT1(8)
---	DAT2(9)
---	DAT3(1)
CSB	---		CSB pull-up in module
VCC	VCC (4)	3.3V
GND	VSS(3,6)	GND

Install

SlibBME280.lua -- Copy to somewhere in Lua's search path.

Parameters settings

Please see the BME280 datasheet for details.

Controls the sensor mode of the device

mode	Mode
0	Sleep mode
1 2	Forced mode
3	Normal mode

Controls inactive duration tstandby in normal mode

t_sb	tstandby [ms]
0	0.5
1	62.5
2	125
3	250
4	500
5	1000
6	10
7	20

Controls the time constant of the IIR filter

filter	Filter coefficient
0	Filter off
1	2
2	4
3	8
4 others	16

Controls oversampling of temperature data

osrs_t	Temperature oversampling
0	Skipped
1	oversampling x1
2	oversampling x2
3	oversampling x4
4	oversampling x8
5 others	oversampling x16

Controls oversampling of pressure data

osrs_p	Pressure oversampling
0	Skipped
1	oversampling x1
2	oversampling x2
3	oversampling x4
4	oversampling x8
5 others	oversampling x16

Controls oversampling of humidity data

osrs_h	Humidity oversampling
0	Skipped
1	oversampling x1
2	oversampling x2
3	oversampling x4
4	oversampling x8
5 others	oversampling x16

Usage

If sadr is nil, it will scan the target address.
If other parameter is nil, default values is used.

command	description <nil for default>
res = BME280:setup( sadr, frq, mode, t_sb, filter, osrs_t, osrs_p, osrs_h) or res = BME280:setup{ sadr=xx, frq=xx, mode=xx, t_sb=xx, filter=xx, osrs_t=xx, osrs_p=xx, osrs_h=xx} example: res = BME280:setup()	Setup BME280 res: Same as return value of fa.i2c(). sadr: I2C target address (7bit) <auto scan> frq: I2C clock frequency. (45 or 100 or 189 or 40) <400> mode: Controls the sensor mode of the device. <3> t_sb: Controls inactive duration tstandby in normal mode. <0> filter: Controls the time constant of the IIR filter. <4> osrs_t: Controls oversampling of temperature data. <2> osrs_p: Controls oversampling of pressure data. <1> osrs_h: Controls oversampling of humidity data. <5>
res, temp, humi, pres, alti, thi = BME280:readData( pres_sea ) example: res, temp, humi, pres = BME280:readData()	Read environmental value res: Same as return value of fa.i2c() temp: temperature [DegC] (-45..85) humi: humidity [%rH] (0..100) pres: pressure [hPa] (300..1100) alti: altitude [m] thi: temperature-humidity index [%] (0..100) pres_sea: sea-level pressure[hPa] <1013.25>

Licence

MIT

Author

GitHub/AoiSaya
Twitter ID @La_zlo