rusefi.com

Posted: **Thu Mar 13, 2025 3:57 pm**

We are in the fine tune stages of our 125 2 stroke uaefi.
We have the LPS22H sensor installed and correctly placed. However no value is shown for barometric pressure. (SDA SCL pins are correctly set)
In the process of trying to get it to talk to the stm I saw that ALPHA N doesn't have barometric correction.
Why is that?
I think barometric correction is crucial for us because we are racing in Spain (see level) and mountain races over the year, furthermore we are 24h races. I do not want to retune the complete engine map every time the pressure changes.

We could use speed density and use TPS as y axis to have barometric correction. Is this the way to go?

Also what could be the reason I get no values from the LPS? Had anyone ever problems with it? Or is anybody using it?

Posted: **Fri Mar 14, 2025 5:54 pm**

https://github.com/rusefi/rusefi/wiki/rusEFI-Quick-Start-PDF is attempting to state that without any info we cannot really help

Posted: **Thu Apr 03, 2025 10:03 am**

Hello more info for clarification. our board is the uaefi rev. d produced by JLCPCB. I checked the orientation of the chip and all effecting souroundings. It all looks fine. Also not much to it.

image.png

My first question is: Why is there no barometric correction in Alpha/N mode in TunerStudio?

image.png

My second question is why is the LPS22 not working? And if it is working in general with our firmware.
We have the correct settings for SCL and SDA.

image.png

our firmware is

image.png

When I connect an Oscilloscope to PB10 and PB11 I do not see an communication. What could be the reason for this?
I checked the datasheet. SDO/SA0 is connected to gnd so adreess is 5Ch. like stated in firmware/hw_layer/sensors
/lps25.cpp:

Code: Select all

#include "pch.h"

#include "lps25.h"

static constexpr uint8_t addr = 0x5C;
static constexpr uint8_t expectedWhoAmILps22 = 0xB1;
static constexpr uint8_t expectedWhoAmILps25 = 0xBD;

Any hint is much appreciated.
Keep on racing
Andreas

rusefi.com

Alpha N and barometric correction / LPS22

Alpha N and barometric correction / LPS22

Re: Alpha N and barometric correction / LPS22

Re: Alpha N and barometric correction / LPS22