[nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Wed, 03 Aug 2022 03:04:34 GMT

https://github.com/adafruit/Adafruit_MAX31865 adapted from C++ to C then added CS/MOSI/MISO GPIO pins as high or low

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

Naing — Wed, 03 Aug 2022 02:35:53 GMT

May I know which library adapted? Thanks

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Wed, 03 Aug 2022 00:09:49 GMT

hi @Naing I ended up manually adding in calls to set CS/MOSI/MISO GPIO pins as high or low before and after each

nrf_drv_spi_transfer() call.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

Naing — Mon, 01 Aug 2022 03:01:52 GMT

Any chance we can get our hands on the adapted MAX31865 library for nrf? I can't seem to find it anywhere else. Otherwise, I'm gonna have to create one myself, so any guidance is welcomed.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

A_J — Fri, 10 Dec 2021 06:57:56 GMT

hello,

I want to create a project with nrf 52832 with max31865 and pt 100 rtd can u help

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

haakonsh — Tue, 27 Jul 2021 11:39:18 GMT

So sorry for the far too long wait-time.

The problem is the jumper-wires and/or connectors, it should noy occur on a PCBA.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

KM123 — Tue, 13 Jul 2021 07:38:36 GMT

I have followed the same steps making CS pin high and low every time transferring data but result i am not getting anything.

can you share your code it would be great thanks in advanced

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Mon, 12 Jul 2021 22:53:01 GMT

Hi KM123

I was able to fix my issue with the MAX31865 development board! I ended up having to hardcode in pulling the CS GPIO pin high or low throughout the code where ever a SPI write or read occurred. I am currently waiting on a PCB delivery to test this code with the MAX31865 chip itself.

I hope this helps.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

KM123 — Thu, 08 Jul 2021 09:49:56 GMT

Hi kmcn

Is your problem solved. I am facing similar type of issue with max31865.
if you have solved then please help me.

thanks

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Tue, 18 May 2021 23:13:30 GMT

Hi here is a picture of the hardware set up.

Red - 5V / Power

Black - GND

Grey - SDI/MOSI - 29

Purple - SDO/MISO - 30

Blue - CS - 31

White - CLK - 26

The RDY pin on MAX31865 is NC as it is NC on the working Arduino set up. The MAX31865 breakout board is 5V compliant and has a voltage regulator on board to drop the power supply to 3.3V.

(The other wires on the breakout board are the Logic analyser).

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Tue, 18 May 2021 10:43:26 GMT

Hi,

Yes I'm using the nRF52840DK with jumper wires to the Maxim device on a breadboard. Nothing else is connected to the breadboard.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

haakonsh — Tue, 18 May 2021 10:36:12 GMT

We need to verify the HW before we start digging into the SW (which seems to be correctly initialized).

What is your HW platform?
Are you using the nRF52840DK with jumper wires to the Maxim device?

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Fri, 14 May 2021 04:25:49 GMT

Hi again,

I've been able to get a hold of a logic analyser to look the SPI in better detail. The below pictures compare the difference between the SPI comms from the Arduino and the SPI from the Nordic. Both SPI have been set with the same clock frequency(1M) and mode (CPOL 0, CPHA 1). I've tried enabling the MOSI and MISO pins to a high drive strength with NRF_GPIO_PIN_H0H1 and am still not able to receive back data on the MOSI line for the Nordic.

The MOSI lines are different between the devices but I have not been able to determine why.

Arduino:

Nordic:

Thanks

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

haakonsh — Thu, 29 Apr 2021 08:50:09 GMT

The SPI Lines are way too capacitively loaded, are you breadboarding or using long jumper wires? I think you need to improve the grounding significantly.

I also suggest that you enable high drive strength for the SPI pins. See nrf_gpio_cfg and nrf_gpio_pin_drive_t.

Use NRF_GPIO_PIN_H0H1.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Wed, 28 Apr 2021 23:16:16 GMT

Hi,

This is the best signal I get from the oscilloscope currently.

MOSI:

CLK:

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

haakonsh — Wed, 28 Apr 2021 11:08:35 GMT

Can you show me a scope?

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

kmcn — Wed, 28 Apr 2021 10:05:17 GMT

Hi,

Yes I've looked at the SPI comms using an oscilloscope and there is no output from the MOSI/MISO pins and the clock waveform is not square. The RX buffer is empty and it appears as if the pins are not being initiated.

RE: [nRF5 SDK v17.0.2] SPI with MAX31865 not receiving

haakonsh — Wed, 28 Apr 2021 09:50:38 GMT

[quote user=""]Currently I am unable to receive back any value from the sensor even though the SPI transfer is completed.[/quote]

What do you mean? Is the RX buffer empty?

Do you have a scope of the SPI communication?