LSM9DS1. DRDY_M pin

[sergeyvslnko]

Posted on January 16, 2018 at 11:10

In the datasheet say that this pin must be work(indicate moment of magnetometer new data avalaible ) automatically(without need of configuration), but it doesn't work. Why?

In the

http://www.st.com/resource/en/datasheet/iis2mdc.pdf

said that M_XYZ_DA status bit must be connected with DRDY_M output pin(page 32,

CFG_REG_C (62h) 0 bit

). D

oes not LSM9DS1 datasheet contain complete information?

This question(

https://community.st.com/0D50X00009XkhX7SAJ

) has proved this  assumptionnull

[Miroslav BATEK]

Posted on January 17, 2018 at 12:39

The DRDY_M signal is available without any configuration.

Do you read the data from the magnetometer? If not the DRDY is set and stay high until you read the data.

[sergeyvslnko]

Posted on January 17, 2018 at 13:50

After magnetometer initialization DRDY_M set up to HIGH. When I first read mag data it set to LOW and... it was staying LOW until power reset action

in spite of

magnetometer data were correctly read again and again.

I have decided this issue when change configuration value of

CTRL_REG3_M (22h)

register from 0x84 to 0x04(7th

bit setting disable I2C interface

). How I2C interface is connected with DRDY_M signal? PS

Batek.Miroslav

, thank you,

your attention helped to solve this problem

.

[Miroslav BATEK]

Posted on January 17, 2018 at 14:16

Do you want to say that the DRDY_M stop work when you set CTRL_REG3_M (22h) to 0x04 and it works if the value is 0x84?

I'm not able replicate this issue.

[sergeyvslnko]

Posted on January 17, 2018 at 14:38

conversely

, it is work when 0x04

is written

to CTRL_REG3_M (22h)

register

and doesn't work when - 0x84.

This is my experience..

[Miroslav BATEK]

Posted on January 18, 2018 at 14:31

I suppose you have some error in HW connection, because the CTRL_REG3_ doesn't have any impact on DRDY_M signal.

Are you really using 3-wire SPI mode (CTRL_REG3 = 0x04)?

I tested it with CTRL_REG3 = 0x00, 0x84, 0x04 and DRDY_M works for all of them.

[sergeyvslnko]

Posted on January 19, 2018 at 12:02

Miroslav, do you use DRDY_M signal as indicator of new mag. data

availability and read the data by that signal? Or do you read the data regardless of the DRDY_M signal and are you only watching the signal?

Please, also try with CTRL_REG3 = 0x80