ESP32 read I2C speed increase

[stefan.erni]

I have IDF Version: v5.0.6 ...
On another computer I have 5.31 and it's compiling and running there.
I'm now trying to read data from the my IMU

[mnfisher]

Did it work? Any benefits?

Martin

[stefan.erni]

Hi Martin

Yes, it has improved,
but there is something extra at the end. I'll see what it is.

Do I have to start with FCD_ in the variables and take the definition out of the loop and put the variable definition at the beginning of the main?

It is very nice that I can set the clock to 1.2Mega

I assume that reading now only takes 120uSec, maybe a bit tight if I have to sample with 8Khz:)
Do you know how I can test this?

polling mode can help to reduce your 50 µs pause because it avoids the overhead of interrupts. If you want to test it, try portMAX_DELAY as timeout for i2c_master_cmd_begin()

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[mnfisher]

Yes - it sort of trades the delay at the beginning for one at the end.. A little quicker though..

Could use FC variables - local start with FCL_ global with FCV_ (capitalised name too)

Martin

[stefan.erni]

Hi Martin

I have additional measurements with FC10 and a PIC32 and with an ESP32 but with a Python compiler.
So Flowcode seems to work well.

I guess it's time to look at I3C

From a microchip PIC32MZ2048 and FC10, with two breaks:

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From an ESP32 and Python compiler, mega long long time break...

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[mnfisher]

It is odd isn't it...

Is maybe an issue with the transactional nature of i2c (I suspect none of the above support direct control of the i2c using Start, Stop etc - but it might be fun to try a chip that does)

Is there an SPI version??

Martin

[stefan.erni]

I'm still looking at an STM32F405


Yes I have a spi version of the chip

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[mnfisher]

That should allow a faster read rate - hopefully. The gyro might have a maximum update speed?

Martin

[stefan.erni]

Hi Martin

Yes Accelero and Gyro can be used with 8kHz.

A problem is the size from the spi version, I2C is much smaler
and the I2C version is reaydy to use with I3C.

So I test first with the spi version an hope I3C with Flowcode will follow soon.

I will simply change the component Gyro_L3GD20 ( spi)

Size from both:

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[mnfisher]

The esp32-p4 should support i3c.

Flowcode (v11!) too?