Arduino nano ble issue on spi

Hi all, I’m using arduino nano 33 ble with Segger J-Link EDU mini . mbed os 6.8 and mbed studio 1.3.1
blinking hello world is ok, usb comunication is ok and now I try to use a tft with ILI9341. But failing to make it work… :frowning:

I reduced the code to a minimum and tried simple SPI initialization:

#define LIGHT 0

#define DARK 1

DigitalOut led_red(LED_RED,DARK);

DigitalOut led_green(LED_GREEN,DARK);

DigitalOut led_blue(LED_BLUE,DARK);
SPI spi(SPI_PSELMOSI0, SPI_PSELMISO0, SPI_PSELSCK0); // mosi, miso, sclk

DigitalOut cs(p23);
int main()

cs = 1;

// Setup the spi for 8 bit data, high steady state clock,
// second edge capture, with a 1MHz clock rate

// Select the device by seting chip select low
cs = 0;

// Send 0x8f, the command to read the WHOAMI register

// Send a dummy byte to receive the contents of the WHOAMI register
int whoami = spi.write(0x00);
printf(“WHOAMI register = 0x%X\n”, whoami);

// Deselect the device

cs = 1;

while (true) {



but the board turns on LED1 ( defined in pinnames.h) is it an error code? I saw from the mbed code that led1 is used flashing as an error code. But the led always on I did not find anything.Maybe I need to edit some json config files. Any ideas?

thanks Marco


yes, 4x long, 4x short blink indicates Mbed OS crash.
If led only came on and stay, then it seems more like complete freeze.

BR, Jan

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