~ cd интегратор: цифровой и аналоговый элемент схемы

module integr(data, clk, reset, out, cn);
    // 1 - включение коэф дискретизации, 0 - отключение
    parameter KOEF_ENA = 1;
    // мой пример... Частота дискретизации 500 КГц. 1/500 = 0.002
    // В данном случае точечная нотация с фиксированой точкой 1.15
    // следовательно. 0.002*(2**16) = 65.536 => PERIOD = 65
    parameter [15: 0] PERIOD = 82;
    parameter DATA_WIDTH = 16;

    input [(DATA_WIDTH - 1): 0] data;
    input reset, clk;
    output [(DATA_WIDTH - 1): 0] out;
    output [(DATA_WIDTH - 1): 0] cn; // переполнение

    wire [(DATA_WIDTH*2 - 1): 0] koef_after;
    wire [(DATA_WIDTH - 1): 0] add1;

    reg [(DATA_WIDTH - 1): 0] z1 = 0;

    generate
        if (KOEF_ENA) begin
            unsigned_multiply #(DATA_WIDTH - 1) mult1(PERIOD, data, koef_after);
        end else begin
            assign koef_after = {data, 15'h00};
        end
    endgenerate

    assign {cn, add1} = (koef_after >> 15) + z1;
    assign out = add1;

    always @(posedge clk, posedge reset) begin
        if (reset) begin
            z1 <= 0;
        end else begin
            z1 <= add1;
        end
    end

endmodule

module unsigned_multiply
#(parameter WIDTH=8)
(
    input [WIDTH-1:0] dataa,
    input [WIDTH-1:0] datab,
    output [2*WIDTH-1:0] dataout
);

    assign dataout = dataa * datab;

endmodule

#include "stm32f4xx_hal.h"

SPI_HandleTypeDef hspi;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_Init(void);

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_SPI1_Init();

  uint8_t receivedData;
  uint32_t sum = 0;

  while (1)
  {
    HAL_SPI_Receive(&hspi, &receivedData, 1, HAL_MAX_DELAY);
    sum += receivedData; // Простой интегратор, складываем принятые данные
  }
}

void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLM = 16;
  RCC_OscInitStruct.PLL.PLLN = 336;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4;
  RCC_OscInitStruct.PLL.PLLQ = 7;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
  {
    Error_Handler();
  }
}

static void MX_SPI1_Init(void)
{
  hspi.Instance = SPI1;
  hspi.Init.Mode = SPI_MODE_SLAVE;
  hspi.Init.Direction = SPI_DIRECTION_2LINES;
  hspi.Init.DataSize = SPI_DATASIZE_8BIT;
  hspi.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi.Init.CRCPolynomial = 10;
  hspi.Init.NSS = SPI_NSS_SOFT;
  hspi.Init.FirstBit = SPI_FIRSTBIT_MSB;

  hspi.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_256; // Настройка скорости передачи
  hspi.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;

  if (HAL_SPI_Init(&hspi) != HAL_OK)
  {
    Error_Handler();
  }
}