如何通过重复代码制作单个功能？

Question

我正在为嵌入式系统编写一些代码。当我在同一外围设备上添加更多不同的通道时，我得到的是真正重复的代码。例如：

void pos1_write_read(int *pwriteData)
{
    // Reset rx buffer and transfer done flag
    memset(m_rx_buf0, 0, m_length0);
    spi0_xfer_done = false;

    nrfx_spi_xfer_desc_t m_pos1_write;
    m_pos1_write.p_tx_buffer = pwriteData;
    m_pos1_write.tx_length = m_length0;
    m_pos1_write.p_rx_buffer = m_rx_buf0;
    m_pos1_write.rx_length = m_length0;

    nrf_gpio_pin_clear(SPI0_CS0_PIN);   //Set CS0 to 0 (on)
    APP_ERROR_CHECK(nrfx_spi_xfer(&spi0, &spi0_transfer, NULL));

    while (!spi0_xfer_done){}           //Wait until the tranfser is done

    nrf_gpio_pin_set(SPI0_CS0_PIN);     //Set CS0 to 1 (off)

}

void pos2_write_read(int *pwriteData)
{
    // Reset rx buffer and transfer done flag
    memset(m_rx_buf0, 0, m_length0);
    spi0_xfer_done = false;

    nrfx_spi_xfer_desc_t m_pos2_write;
    m_pos2_write.p_tx_buffer = pwriteData;
    m_pos2_write.tx_length = m_length0;
    m_pos2_write.p_rx_buffer = m_rx_buf0;
    m_pos2_write.rx_length = m_length0;

    nrf_gpio_pin_clear(SPI0_CS1_PIN);   //Set CS1 to 0 (on)
    APP_ERROR_CHECK(nrfx_spi_xfer(&spi0, &spi0_transfer, NULL));

    while (!spi0_xfer_done){}           //Wait until the tranfser is done

    nrf_gpio_pin_set(SPI0_CS1_PIN);     //Set CS1 to 1 (off)

}

我将如何编写可以在两个示例中使用的单个函数？是否有任何一般的好习惯来避免重复相同的代码？

Answer 1

找到正确的设计取决于打算如何使用它，您感觉通用性如何，等等。没有唯一正确的方法可以做到这一点。但是仅基于您的代码段的幼稚解决方案是这样的：

void write_read(int *pwriteData, int pin)
{
    // Reset rx buffer and transfer done flag
    memset(m_rx_buf0, 0, m_length0);
    spi0_xfer_done = false;

    nrfx_spi_xfer_desc_t m_pos1_write;
    m_pos1_write.p_tx_buffer = pwriteData;
    m_pos1_write.tx_length = m_length0;
    m_pos1_write.p_rx_buffer = m_rx_buf0;
    m_pos1_write.rx_length = m_length0;

    nrf_gpio_pin_clear(pin);   //Set CS0 to 0 (on)
    APP_ERROR_CHECK(nrfx_spi_xfer(&spi0, &spi0_transfer, NULL));

    while (!spi0_xfer_done){}           //Wait until the tranfser is done

    nrf_gpio_pin_set(pin);     //Set CS0 to 1 (off)

}
void pos1_write_read(int *pwriteData)
{
    write_read(pwriteData, SPI0_CS0_PIN);
}

void pos2_write_read(int *pwriteData)
{
    write_read(pwriteData, SPI0_CS1_PIN);
}

想法是采用通用代码，然后对它们之间的不同之处进行参数化。

Answer 2

唯一真正的区别是SC引脚，您可以将其作为参数传递：

void pos_write_read(int *pwriteData, uint32_t pin)
{
    // Reset rx buffer and transfer done flag
    memset(m_rx_buf0, 0, m_length0);
    spi0_xfer_done = false;

    nrfx_spi_xfer_desc_t m_pos_write;
    m_pos_write.p_tx_buffer = pwriteData;
    m_pos_write.tx_length = m_length0;
    m_pos_write.p_rx_buffer = m_rx_buf0;
    m_pos_write.rx_length = m_length0;

    nrf_gpio_pin_clear(pin);   //Set CS to 0 (on)
    APP_ERROR_CHECK(nrfx_spi_xfer(&spi0, &spi0_transfer, NULL));

    while (!spi0_xfer_done){}           //Wait until the tranfser is done

    nrf_gpio_pin_set(pin);     //Set CS to 1 (off)
}

/* This allows you to do the following: */

void pos1_write_read(int *pwriteData)
{
    pos_write_read(pwriteData, SPI0_CS0_PIN);
}


void pos2_write_read(int *pwriteData)
{
    pos_write_read(pwriteData, SPI0_CS1_PIN);
}