jensa
Member

I've been stuck on other projects for some days now, but my coworker found that changing clock and reducing speed was a good solution to keep things stable without removing transactions. It really annoys me that I...

@mjs513 The SPI mode difference is just since you're looking at https://github.com/adafruit/Adafruit_MAX31865 rather than https://github.com/adafruit/Adafruit-MAX31855-library ;-) (The MAX31865 is for PT100 sensors,...

Not if calling SPI.begin()? https://github.com/PaulStoffregen/SPI/blob/master/SPI.cpp#L1314 J

@guzo could you try commenting out the beginTransaction & endTransaction in the Adafruit Lib? That solved the problem for me, but I still are unable to reproduce this with just a T4.1 on Breadboard.

I tried reproducing the bug with a stock T4.1 on breadboard with 3 MAX31855's to no avail. I only had 3 breakout boards, but I don't seen how the amount of SPI devices could be relevant other than for signal quality. It...

Weekend and refurbishing got me, but now it's Monday and I found the culprit. It's related to the transactions and multiple IC's. If I remove beginTransaction and endTransaction, it works flawlessly on any speed. I'll...

As mentioned, it does not crash with a stock T4.1 and the chip on a breadboard :-/ It has to do with SPI on my board specifically. J

Huh... The plot thickens. I initially tested with varying speeds from 0.5-10Mhz. It kept crashing no matter the speed. After I tried the "fix" above, I could not make it crash. This was at 10Mhz and I didn't try...

So now I've tested with an original T4.1 + the part on a breadboard and I cannot reproduce the problem. That indicates that the error is somewhere in my custom board. Looking at the signals with a scope, the levels look...

Let me drop by my customer tomorrow to pick up some MAX31855's for testing with an original T4.1 on a breadboard before you order anything? I'm thinking it's likely the Microchip part that is the problem here. I'll test...

Using either just zeros or nullptr does not change the behavior. Unfortunately, the chip is required it seems? This is the most compact code I could come up with that let you test both variants. #include...

It's ok and it works? :) The next time I lay out this chip I'll be sure to read all of the PJRC page on this https://www.pjrc.com/store/ic_mkl02_t4.html. Scroll down and you'll find a great strategy for getting better...

@Srx Shouldn't be hard if you have a hot-plate. Does not need to be big either. I used the MiniWare MHP30 (https://www.youtube.com/watch?v=JKlTd1B6Au8). It's tiny, but perfect for doing stuff like this & reflowing IC's....

Thanks! I found exactly what I need there. Great suggestion @luni! This validates what I found in the datasheet, so now I can add the supported pins to my custom T4.1 board.

Digging deep into the 3500+ page reference manual for the imxrt1060 series, I found details on GPT in chapter 52 and TMR in chapter 54 in Gated-Count Mode. I'll research this further. It would still be very useful to...

Thanks! I'll desolder and test! J