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OverTheTop

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SparkyVTFlyer

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Specs look nice, especially the self-calibration ability, but its quite a large package at 15mm x 15mm and my quick look doesn't see I2C capability. At $147 its very pricey too. The ICM-20649 can do 30Gs and is much less expensive. Adafruit even makes a breakout board for $15. https://www.adafruit.com/product/4464

My personal favorite is the LSM9DS1. Its 9 DOF (accel, gyro, mag) and 24G capable. I use this in conjunction with the H3LIS331DL, 100G-400G accelerometer, with good results.
 

SparkyVTFlyer

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Many people would see that as an advantage :p.
Well, most devices like this have I2C capability. SPI only eliminates the possibility of a "drop in" replacement. Even though I2C is limited typically to 400kbps, its still possible to get a high sample rate. I use I2C to get data from the LSM9DS1 and H3LIS331DL at over 1400Hz, and still have enough cycle time with a Teensy3.5 to do everything else I need (physics model, event logic, SD card data capture, GPS, telemetry, etc).
 

heada

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Well, most devices like this have I2C capability. SPI only eliminates the possibility of a "drop in" replacement. Even though I2C is limited typically to 400kbps, its still possible to get a high sample rate. I use I2C to get data from the LSM9DS1 and H3LIS331DL at over 1400Hz, and still have enough cycle time with a Teensy3.5 to do everything else I need (physics model, event logic, SD card data capture, GPS, telemetry, etc).
Try with the Teensy 4. Blazingly fast!
 

OverTheTop

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I2C is a relatively common protocol (not sure about the "most" in your statement above) but is more complex to implement than SPI. Most people (hardware and firmware) that I know will choose SPI over I2C every time, if given the chance and not constrained by other parameters.

I did post this thread for information on the new device, not necessarily to get into a protocol debate.
 

heada

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Most micro controllers support both SPI and I2C. After that, if the library is provided, then either are just about the same.

Back to the original subject, are there any libraries written for it yet?
 

SparkyVTFlyer

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I did post this thread for information on the new device, not necessarily to get into a protocol debate.
I agree. I just wanted to highlight a potential limitation of this device from a user's perspective.

Try with the Teensy 4. Blazingly fast!
Eventually I will get there, but the backside components of the Teensy4.X limits the usability for my purposes. I have to design entirely new boards to integrate it as I need. But yes, the 64-bit FPU capability and speed are very, very interesting.
 

XrayLizard

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Specs look nice, especially the self-calibration ability, but its quite a large package at 15mm x 15mm and my quick look doesn't see I2C capability. At $147 its very pricey too. The ICM-20649 can do 30Gs and is much less expensive. Adafruit even makes a breakout board for $15. https://www.adafruit.com/product/4464

My personal favorite is the LSM9DS1. Its 9 DOF (accel, gyro, mag) and 24G capable. I use this in conjunction with the H3LIS331DL, 100G-400G accelerometer, with good results.
Just do not expect any direct support from ST on those (or any ST) products.
Signed,
Former ST support tech
 

OverTheTop

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Just do not expect any direct support from ST on those (or any ST) products.
Signed,
Former ST support tech
Interesting. We had some support issues with ST recently. They had some dodgy triacs (root cause was the corners of the dies were chipped when separating them off the wafer) and they were as unreliable a hell. The fix was to switch to a different brand. Sad to hear as ST used to be really good to deal with many years ago.
 

XrayLizard

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yes Sir.
you are lucky if you even get to an apps or other engineer.
Of the people who work there...at the support center, they just play on cell phones all day long. Whwn they are not playing on cell phones then the are probably on a second hour long break followed by lunch. Or, they may be arguing that spiderman can beat Hulk. Or discussing the managers choice of lifestyle and that he is a racist, etc,etc,etc. (even though he can hear them)

A support ticket wont get looked at until it is time for those 40+ year olds who live with thier parents (really) to make their weekly quota.
unless you get "seagate doug". You will know because he will spend 20 or 40 munites reading a datasheet to you..with no comprehension of what it says...lol
Then of course you have to hope they escalate your request. Yours will go, at best to eng. in your region. God help you if you use a gmail or yahoo email address.

the direct manager and the next level up are responsible for this lack of action, along with an attitude out of Europe. Nether one has an engineering background.

I always looked for certain tickets to take care of. certain people who have similar interests here and elsewhere. Did my best. Now I am just flunking at a setting up VCSEL wafer probe machines. dambit it all. sure wish I had chosen a career at Walmart...

sitting here now dealing with programmers in India. asking me to do their work so to speak. not going to happen. 63 and ready to get covid or retire lol
 

XrayLizard

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if you buy an ST-Eval board the support is in Italy, Good, smart group. very very swamped and overworked. any eval board without "st" prefix. no luck.

Microcontrollers are different. ALL microcontrollers get escalated...that is whenever the lazy people there decide to look at and escalate the request.
It is against the rules so to say to esclate any other support requests, unless its from Apple, google, etc.

you should have seen the ClusterF from the rare earth thing a year ago......omg.
actually, and this is not what a lot of folks realize, many many many many plus infinity requests are for EHS... IE EPA, IE Kalifornia. The orverhead to our corporations is ungodly, and I am sure you are well aware, but so many are not.
 
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heada

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Good break down of various microcontrollers. Since you have to do all the math yourself for this IMU you'll need something with a bit of grunt.
 

XrayLizard

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I do advise young bucks and does to get into ARM and DSP, either that or Walmart. or maybe Finance. Either way we all get sucked into the machine and spit out eventually! lol.
In my weak defense I do know how to build a tube guitar amp haha
 

OverTheTop

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Now I am just flunking at a setting up VCSEL wafer probe machines.
Interesting. One of our division designed a VCSEL specifically for one of our spectrometers. Neat unit. Needless to say development costs were not insignificant, but the outcome was outstanding.
Think like google maps for imaging tablets and other samples. How far do you want to zoom? Oh, and you get spectroscopic analysis with that :). The special VCSEL makes it possible.

I think my thread is drifting... 😆
 

OverTheTop

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I do advise young bucks and does to get into ARM and DSP
More and more is being pulled into the digital domain so this is likely good advice. Software-defined radio is a good example. We are looking for a digital engineer currently. One left recently and he had particular expertise we valued.
 

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