ESP32 Forum

Posted: **Sat Jan 27, 2024 3:49 pm**

Hello,
I have got XIAO ESP32S3 and ESP32-WROOM32 units. I have got exactly the same problem on both. SPI works on Arduino but it does not on ESP-IDF. I use ESP-IDF 5.1.2.

I setup SPI by using code below. Later I send 4 bytes

Code: [Select all] [Expand/Collapse]

//On XIAO I tried
        //gpio_iomux_in(GPIO_NUM_9, SPI3_D_IN_IDX);
        //gpio_iomux_out(GPIO_NUM_8, SPI3_Q_OUT_IDX, false);
        //gpio_iomux_in(GPIO_NUM_7, SPI3_CLK_IN_IDX);
        //gpio_iomux_in(GPIO_NUM_1, SPI3_CS0_IN_IDX);
        // and this
        //gpio_iomux_out(GPIO_NUM_9, SPI3_D_OUT_IDX, false);
        //gpio_iomux_in(GPIO_NUM_8, SPI3_Q_IN_IDX);
        //gpio_iomux_out(GPIO_NUM_7, SPI3_CLK_OUT_IDX, false);
        //gpio_iomux_out(GPIO_NUM_1, SPI3_CS0_IN_IDX,false);
 
        spi_bus_config_t Config;
        Config.mosi_io_num = GPIO_NUM_23;//GPIO_NUM_9;//GPIO_NUM_13;//
        Config.miso_io_num = GPIO_NUM_19;//GPIO_NUM_8;//GPIO_NUM_12;//
        Config.sclk_io_num = GPIO_NUM_18;//GPIO_NUM_7;//GPIO_NUM_14;//;
        //Config.mosi_io_num = GPIO_NUM_9;
        //Config.miso_io_num = GPIO_NUM_8;
        //Config.sclk_io_num = GPIO_NUM_7;
        Config.max_transfer_sz = 0;
        Config.quadwp_io_num = -1;  // -1 not used
        Config.quadhd_io_num = -1;  // -1 not used
        Config.intr_flags = 0;
        Config.data0_io_num = -1;
        Config.data1_io_num = -1;
        Config.data2_io_num = -1;
        Config.data3_io_num = -1;
        Config.data4_io_num = -1;
        Config.data5_io_num = -1;
        Config.data6_io_num = -1;
        Config.data7_io_num = -1;
        //Tried with SPICOMMON_BUSFLAG_NATIVE_PINS, SPICOMMON_BUSFLAG_NATIVE_PINS, SPICOMMON_BUSFLAG_GPIO_PINS
        Config.flags = SPICOMMON_BUSFLAG_MASTER;// | SPICOMMON_BUSFLAG_NATIVE_PINS;// | SPICOMMON_BUSFLAG_MISO | SPICOMMON_BUSFLAG_MOSI;
        Config.isr_cpu_id = INTR_CPU_ID_0;
        if(ESP_OK == spi_bus_initialize(SPI3_HOST, &Config, SPI_DMA_CH_AUTO))//SPI_DMA_DISABLED);//SPI_DMA_CH_AUTO);
        {
            printf("-----OK-----");
        }  
 
        //spicommon_bus_initialize_io
        spi_device_interface_config_t ConfigInterface;
        ConfigInterface.command_bits = 0;
        ConfigInterface.address_bits = 0;
        ConfigInterface.dummy_bits = 0;
        ConfigInterface.mode = 0;
        ConfigInterface.duty_cycle_pos = 128;  // default 128 = 50%/50% duty
        ConfigInterface.cs_ena_pretrans = 0;  // 0 not used
        ConfigInterface.cs_ena_posttrans = 0;  // 0 not used
        ConfigInterface.clock_speed_hz = 500000;
        ConfigInterface.clock_source = SPI_CLK_SRC_APB; //SPI_CLK_SRC_DEFAULT
        ConfigInterface.spics_io_num = GPIO_NUM_5;
        ConfigInterface.flags = 0;//SPI_DEVICE_HALFDUPLEX | SPI_DEVICE_NO_DUMMY; //| SPI_DEVICE_HALFDUPLEX;
        ConfigInterface.queue_size = 1;
        ConfigInterface.pre_cb = NULL;
        ConfigInterface.post_cb = NULL;
        ConfigInterface.input_delay_ns = 0;
        if(ESP_OK == spi_bus_add_device(SPI3_HOST, &ConfigInterface, &SPIHandle))
        {
            printf("-----OK-----");
        }

GeSHi © Codebox Plus Extension

I receive wrong data, always the same bytes no matter what 4 bytes are sent. Screenshot from logic analyzer:

: ESP-IDF.PNG (81.36 KiB) Viewed 2210 times

When I use Arduino

Code: [Select all] [Expand/Collapse]

#include <Arduino.h>
#include <SPI.h>
 
#define VSPI_MISO   19
#define VSPI_MOSI   23
#define VSPI_SCLK   18
#define VSPI_SS     5
 
SPIClass * vspi = NULL;
 
void setup() 
{
  printf("Start");
  pinMode(VSPI_SS, OUTPUT);
  vspi = new SPIClass(2);
  vspi->begin(VSPI_SCLK, VSPI_MISO, VSPI_MOSI, VSPI_SS); //SCLK, MISO, MOSI, SS
}
 
void loop() 
{
  //uint16_t addressToRead = 0x0740;
  uint16_t addressToRead = 0x08E7;
  vspi->beginTransaction(SPISettings(500000, MSBFIRST, SPI_MODE0));
  delay(10);
  digitalWrite(VSPI_SS, 0);  
  vspi->transfer(0x0D); 
  vspi->transfer16(addressToRead);
  vspi->transfer(0x38);  
  digitalWrite(VSPI_SS, 1);  
  vspi->endTransaction();
  
delay(2000);
 
  vspi->beginTransaction(SPISettings(500000, MSBFIRST, SPI_MODE0));
  delay(10);
  addressToRead = 0x08E7;
  digitalWrite(VSPI_SS, 0); 
  vspi->transfer(0x1D); 
  vspi->transfer16(addressToRead);
  vspi->transfer(0x00);  
  uint8_t regValue = vspi->transfer(0x00);  
  digitalWrite(VSPI_SS, 1);  
  vspi->endTransaction();
  printf("Reg %u", regValue);
  delay(2000);
  printf("Stop\n");
}

GeSHi © Codebox Plus Extension

Everything is correct. I can write and read data without problems. Screenshot from logic analyzer below. Everything is fine.

: Arduino.PNG (85 KiB) Viewed 2210 times

When I start program on Arduino later on ESP-IDF you can clearly see differences on logic analyzer

: Both.PNG (71.5 KiB) Viewed 2210 times

Hardware connection is fine because it works on Arduino. It is something wrong with configuration on ESP-IDF (I have spent lots of time trying different configurations). It is something incorrect with PINS or MOSI or CLOCK or ... . Behavior is the same on XIAO ESP32s3 and ESP32 units ( I reconfigure pins of course ). Tried VSPI and HSPI.

Did someone have similar issue?

Posted: **Sun Jan 28, 2024 4:37 pm**

Hi,
I have resolved the issue. I have noticed that mosi_io_num and data0_io_num are union. Also miso_io_num and data1_io_num.

union {
int mosi_io_num; ///< GPIO pin for Master Out Slave In (=spi_d) signal, or -1 if not used.
int data0_io_num; ///< GPIO pin for spi data0 signal in quad/octal mode, or -1 if not used.
};
union {
int miso_io_num; ///< GPIO pin for Master In Slave Out (=spi_q) signal, or -1 if not used.
int data1_io_num; ///< GPIO pin for spi data1 signal in quad/octal mode, or -1 if not used.
};

When these lines are removed everything works fine

Config.data0_io_num = -1;
Config.data1_io_num = -1;

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