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Code: Untitled.c Select all

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <inttypes.h>

#include "freertos/FreeRTOS.h"

#include "freertos/task.h"

#include "esp_system.h"

#include "driver/spi_master.h"

#include "driver/gpio.h"

#include "hal/gpio_types.h"

#include "soc/spi_reg.h"

#include "soc/spi_struct.h"





// SPI2 on ESP32-S3 supports 8-bit Octal SPI mode

#define LCD_HOST    SPI2_HOST 





void spi_post_transfer_callback(spi_transaction_t *t)

{



}



static void send_lines(spi_device_handle_t spi, int ypos, uint8_t *linedata)

{



    esp_err_t ret;

    int x;



    //Transaction descriptors. Declared static so they're not allocated on the stack; we need this memory even when this

    //function is finished because the SPI driver needs access to it even while we're already calculating the next line.

    static spi_transaction_t trans_msg; 

    trans_msg.flags     = SPI_TRANS_MODE_OCT;

    trans_msg.tx_buffer = linedata;      //finally send the line data

    trans_msg.length    = 31000;  //Data length, in bits



//  ret = spi_device_queue_trans(spi, &trans_msg, portMAX_DELAY);

//  assert(ret == ESP_OK);



    ret = spi_device_polling_transmit(spi, &trans_msg); // Transmit!

    assert(ret == ESP_OK);                              // Should have had no issues.



}



void setup() {

  

  // put your setup code here, to run once:

    esp_err_t ret;

    spi_device_handle_t spi;

    

    spi_bus_config_t buscfg = {

        .data0_io_num = 5, // A

        .data1_io_num = 4, // B

        .sclk_io_num =  42, // C

        .data2_io_num = 7, // D

        .data3_io_num = 41, // E

        .data4_io_num = 1, // oe

        .data5_io_num = 6, // lat

        .data6_io_num = 2, // clk

        .data7_io_num = 48, // sr

        .max_transfer_sz = 32768, // ESP32 S3 max size is 64Kbytes

        .flags        = (SPICOMMON_BUSFLAG_OCTAL | SPICOMMON_BUSFLAG_MASTER | SPICOMMON_BUSFLAG_GPIO_PINS), // kinda important      

    };



    //Configure SPI Device

    spi_device_interface_config_t devcfg = {

        .command_bits = 0,

        .address_bits = 0,

        .dummy_bits = 0,      

        .mode = 0,                                  // SPI mode 0

        .duty_cycle_pos = 0,

        .cs_ena_pretrans = 0,

        .cs_ena_posttrans = 0,

        .clock_speed_hz = SPI_MASTER_FREQ_8M,       // Clock out at 10 MHz

        .input_delay_ns = 0,

        .spics_io_num = -1,                         // CS pin



        // SPI_DEVICE_NO_RETURN_RESULT = Don't care abut result 

        //.flags = (SPI_DEVICE_HALFDUPLEX | SPI_DEVICE_NO_RETURN_RESULT), 

        .flags = (SPI_DEVICE_HALFDUPLEX ), 

        .queue_size = 10,                     

        .pre_cb = 0, // Not used

        .post_cb = spi_post_transfer_callback,



    };



    //Initialize the SPI bus

    ret = spi_bus_initialize(LCD_HOST, &buscfg, SPI_DMA_CH_AUTO);

    ESP_ERROR_CHECK(ret);



    //Attach the LCD to the SPI bus

    ret = spi_bus_add_device(LCD_HOST, &devcfg, &spi);

    ESP_ERROR_CHECK(ret);



    size_t max_trans_bytes = 0;

    ret = spi_bus_get_max_transaction_len(LCD_HOST, &max_trans_bytes);

    assert(ret == ESP_OK);    

    ESP_LOGI("S3", "Max transfer size is %u", (uint32_t)max_trans_bytes);        

   



    uint8_t *output_data;

    output_data = (uint8_t *) heap_caps_malloc(31000 * sizeof(uint8_t), MALLOC_CAP_DMA);

    assert(output_data != NULL);



    // Doesn't send data after about the 4096 boundary?

    int offset = 4096;

    memset(output_data, (uint8_t)0x00, 31000);

    memset(output_data+offset, (uint8_t)0xff, 31000-offset); // overwrite from offset with 0xff   

    

    while (1) 

    {

        send_lines(spi, 0, output_data);

    }

  



} // setup



void loop() {

  // put your main code here, to run repeatedly:



}