SPI on SAMD21G18 not working

[malrip]

Hello,

I've been attempting to use SERCOM2 SPI Master on the SAMD21G18J but have been unsuccessful. I tried the configurations with SERCOM0 and SERCOM4, and they both worked. The most intriguing behavior is that when I initialize the SERCOM2 SPI, all of the other I/O pins stop working as well. The clock is not generated, and CS is not operational.

I tried several bootloaders, but the results were the same. To begin, I used the bootloader of an Arduino nano IOT 33, which uses the same chip, in order to use the arduino IDE more easily. Then, I tested with the bootloaders Arduino zero and adafruit M0 bootloader. The idea of testing other bootloarders was because arduino ano iot 33 uses SPI SERCOM2 to communicate with his WIFI module, and could be protected some how. Any insight will be useful.

The schematic is displayed below:
https://community.atmel.com/sites/default/files/forum-images/462842-body-1645030566-1.jpg

The SERCOM2 Pads:
https://aws1.discourse-cdn.com/arduino/original/4X/7/3/9/73938e5c4bae0c9fbcc55e3ba7afc86408f0e02b.png


Main routine: https://www.codepile.net/pile/y6bB1d6w

Header file: https://www.codepile.net/pile/l56XN6x3

 

[snarkysparky]

I look at it quickly so I may have missed something.

I see you setup the slave select.  But you also have to setup the other pins.   Is that somewhere else ?

[malrip]

No problem. I have set to master at line 41: SERCOM2->SPI.CTRLA.bit.MODE = 0x3; //SPI in Master mode
The other pins are set on lines 38, and 39, DIPO and DOPO registers.

[thm_w]

atmel link: https://www.avrfreaks.net/forum/spi-samd21g18-not-working

I'm sure this is unrelated, but, why is pin 18 not connected to Gnd?

Can you try without a bootloader, do you have a proper programmer? But then you'd have to set up clocks, etc.

[malrip]

Oh, I forgot about this pin. If SERCOM2 requires this pin to function, it would be a strange coincidence. I'll solder this pin to ground and see what happens. Yes, I burned the bootloader using Segger J-link and Atmel Studio.