Interfacing (DSI, CSI, I2C, etc.) • issue with spi_read16_blocking with ADC

Hello World !

I'm interfacing a 16bit SPI ADC with RPI PICO 2. have written below code, but it throws output as "65535" always.

Need your expertise and help in know the issue with compiler or code ?

1) Using Arduino 2.0
2) tried different RX pins
3) The RX pin shows the data coming correctly

Here are the related codes for understanding.

void initialize_ADC_LTC2311() {
pinMode(CNV_PIN, OUTPUT);
digitalWrite(CNV_PIN, HIGH);
spi_init(spi1, SAMPLE_RATE);
spi_set_format(spi1, 16, SPI_CPOL_0, SPI_CPHA_0, SPI_MSB_FIRST);
gpio_set_function(SPI_MISO, GPIO_FUNC_SPI);
gpio_set_function(SPI_SCK, GPIO_FUNC_SPI);
}

void readADC() {
static uint16_t sample[4];
for (int i = 0; i < 4; i++)
{
pulseCNV();
spi_read16_blocking(spi1, NULL, &sample, 1);
Serial.println(sample, DEC);
}
}

Statistics: Posted by vinaysharma — Wed Aug 27, 2025 1:30 pm

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