What the best way to read MAX31855?

[mdmubdiulhasan]

Dear All,

 I need to make a SPI for  MAX31855 as it works on unidirectional full duplex mode.

Kindly take a look the SPI protocol and suggest me a best 32bit mcu to read it.

[kerryzhou]

Hi Md Mubdiul Hasan,

    The SPI module on our kinetis chip normally have 4 to 16 bits frame size, not 32 bits.

     So, if you just want to read the MAX31855, you can choose KL series chip, and you have two way to read the sensor.

1. Use KL series, SPI 8 bits frame, and read 4 times, then use the code to combine these 4 bytes to 32bits, the CS please use the GPIO to control it.

2. Don't use SPI module, just use the GPIO for CS, MISO, SCK pin, then use the code to simulate the 32bits reading SPI wave, this may more flexible.

Wish it helps you!

If you still have question, please let me know!
Have a great day,
Kerry

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[mdmubdiulhasan]

Dear Sir Kerry,

Sorry for my late replay.

My  SPI protocol is quite different in case of unidirectional full duplex mode.

Interesting to see how codes have been written in  KL.

Kindly recommend me a suitable KL mcu/kit/eval board along with SPI code.

[kerryzhou · Accepted solution]

Hi Md Mubdiul Hasan,

     About the KL MCU, you can consider to use KL25, board is FRDM-KL25:

FRDM-KL25Z|Freedom Development Platform|Kinetis MCU|NXP 

  About the detail MAX31855 code, we don't have it, we just have the SPI driver, the code you can find from this link:

http://www.nxp.com/assets/downloads/data/en/lab-test-software/KL25_SC.exe 

  Then the SPI code can be found in folder: kl25_sc_rev10\klxx-sc-baremetal\src\drivers\spi

Wish it helps you!

Have a great day,
Kerry

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[mdmubdiulhasan]

Thank you Kerry.

I will suggest my company to buy your product.

Applying different device in different IDE is tough.

STM is different compared with NXE.

Lets see which is more convenient.

[kerryzhou]

Actually, about the IDE, you can use the third part ide which you are familiar, for example:IAR MDK.

About the device, the KL25 is very easy to use.

If you have any problem, welcome to let us know!

Have a great day,
Kerry

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[mdmubdiulhasan]

I have been using mdk-keil, ecilipse, IAR, CO-COOX etc a lot!

Problem is making hard code !

Thousands of SPL will make you puzzled!