Trouble with I2C devices on 2v25

[Nicktonious]

I had troubles with js modules for I2C devices since I switched to 2v25 on STM32F405-based board
First I noticed that my VL6180 no longer works correctly. I had failed to find the exact source of problems so I just re-written the module's logic. Maybe my module originally was inconsistent, but it definitly works on later versions.
What's more important, SHT31 module that has been tested for a long time doesn't work at all: it throws Timeout on I2C Write Transmit Mode 2
Noteworthy, both Vl6180 and SHT31 dont work on Hardware I2C an Software I2C setuped on hardware pins
What to you think about this bug? If you propose some tests, I'm ready to perform them and update my report

Thanks in advance!

[gfwilliams]

What's the clock speed on the F405 board? One thing that did change I recall is the I2C timeout got lowered - I forget exactly but from something like 0.5s to 0.1s - it feels like pretty much every I2C device should respond within under 1ms but maybe some don't?

[Nicktonious]

Clock speed is 168MHz
In a couple of days I'll be able to perform some complex tests on that board and another one. I'll share results ASAP

[gfwilliams]

Maybe try changing this line and rebuild and see if that fixes it? https://github.com/espruino/Espruino/blob/master/src/jshardware.h#L439

The boards we sell are 84Mhz, so 168 would halve the wait time. 2000000 at 168Mhz is probably only 50ms or so?

[ponyatov]

At low level and 100k low speed it works ok:

function test() {
  digitalWrite(A6,0); // trigger line
  I2C1.setup({
    scl:B8, sda:B9,
    bitrate: 100000
  });
  I2C1.writeTo(0x29, 0);
  var x = I2C1.readFrom(0x29, 6);
  digitalWrite(A6,1);
}
test();

[ponyatov]

At 400k I see the same working i/o.

So problem resides in incorrect I2C init or badly sensor high-level driver.

saleae Logic2 traces: i2c_2v25.zip

[gfwilliams]

I'm not sure I understand? So it works at 100k and 400k? When doesn't it work?

[ponyatov]

next test with LPS25HB pressure sensor:
firmware: Espruino 2v25.10
mcu: STM32F405

I see regular but not periodic faults every 2-30 seconds, with requests compressed after fault recovery.

In normal state sensor requests goes every 1 seconds.

Logic2 data: gap_2v25.sal.gz

[ponyatov]

2v25 with increased WAIT_UNTIL_N_CYCLES=5000000:

2v25_5000000.sal.gz

[ponyatov]

LPS25HB driver was omitted, and low-level code was done using sensor datasheet and this sample:
https://github.com/ControlEverythingCommunity/LPS25HB/blob/master/Arduino/LPS25HB.ino

Sensor works in continuous measurement mode (1 Hz) without any problems in a long time.

LPS25HB.js.gz
LPS25HB_raw.sal.gz

• WHO_AM_I
  

• setup
  

• measurement loop (pressure + temperature)