56 在standby待机打通uart调试的方法

修改点如下：

一，进入standby保证uart通

1, 去掉串口进入休眠RT_DEVICE_CTRL_SUSPEND:关闭uart，保证BSP_IO_Power_Down函数执行完前，串口都可以打印，和通过SifliUsartServer工具串口连接，并debug死机问题；

二，从standby唤醒保证uart通

standby唤醒打开串口比较麻烦，此时RTT系统还没有恢复，外部Nor/Nand Flash都没有初始化不可以用，除了Retention RAM外，其他的RAM也还不能访问，打通Uart的思路，就是在GPIO通了HAL_HPAON_ENABLE_PAD();以后，对uart进行初始化配置，并且此时的代码都需要放在RAM内运行，rt_kprintf(""); 在rtt系统和恢复RT_DEVICE_CTRL_RESUME:之前，都是不能打印的，如果一定要打印，用hal_printf("BSP_Power_Up\n");打印，而且不能在if (PM_STANDBY_BOOT == SystemPowerOnModeGet()) 待机唤醒起来的代码内才能运行，其他上电时uart没有初始化，也是会死机；修改点如下：

drv_usart.c文件新增加的hal初始uart的函数和打印函数；

复制代码

/* UART handler declaration */
static UART_HandleTypeDef UartHandle;

#define BUFFER_SIZE 256
#define HALF_BUFFER_SIZE (BUFFER_SIZE/2)
static DMA_HandleTypeDef dma_rx_handle;
static uint8_t buffer[BUFFER_SIZE];


// 定义接收状态枚举
typedef enum
{
    STATE_UNFULL,
    STATE_HALF_FULL,
    STATE_FULL
} ReceiveState;
// 当前接收状态
ReceiveState currentState = STATE_UNFULL;

HAL_RAM_RET_CODE_SECT(HAL_UART_CONFIG, static void HAL_UART_CONFIG(struct sifli_uart_config *cfg, rt_size_t obj_num, rt_uint32_t baud_rate))
{
    /* Output a message on console using printf function */
    for (int i = 0; i < obj_num; i++)
    {

        /*##-1- Configure the UART peripheral ######################################*/
        /* Put the USART peripheral in the Asynchronous mode (UART Mode) */
        /* UART configured as follows:
            - Word Length = 8 Bits (8 data bit + 0 parity bit) :
           BE CAREFUL : Program 7 data bits + 1 parity bit in PC HyperTerminal
            - Stop Bit    = One Stop bit
            - Parity      = No parity
            - BaudRate    = 1000000 baud
            - Hardware flow control disabled (RTS and CTS signals) */
        UartHandle.Instance        = cfg->Instance;
        UartHandle.Init.BaudRate   = RT_SERIAL_DEFAULT_BAUDRATE;
        UartHandle.Init.WordLength = UART_WORDLENGTH_8B;
        UartHandle.Init.StopBits   = UART_STOPBITS_1;
        UartHandle.Init.Parity     = UART_PARITY_NONE;
        UartHandle.Init.HwFlowCtl  = UART_HWCONTROL_NONE;
        UartHandle.Init.Mode       = UART_MODE_TX_RX;
        UartHandle.Init.OverSampling = UART_OVERSAMPLING_16;
        if (UartHandle.Init.Parity)
        {
            // If parity is odd/even, parity should +1
            UartHandle.Init.WordLength = UART_WORDLENGTH_9B;
        }
        /* 1, pinmux set to uart mode */

        HAL_PIN_Set(PAD_PA30, USART1_RXD, PIN_PULLUP, 1);   // UART1_RXD
        HAL_PIN_Set(PAD_PA34, USART1_TXD, PIN_PULLUP, 1);   // UART1_TXD

        /* 2, open uart2 clock source  */
        HAL_RCC_EnableModule(RCC_MOD_USART1);
        if (HAL_UART_Init(&UartHandle) != HAL_OK)
        {
            /* Initialization Error */
            HAL_ASSERT(0);
        }

        // Start RX DMA
        __HAL_LINKDMA(&(UartHandle), hdmarx, dma_rx_handle);
        dma_rx_handle.Instance = cfg->dma_rx->Instance;
        dma_rx_handle.Init.Request = cfg->dma_rx->request;
        HAL_UART_DmaTransmit(&UartHandle, buffer, BUFFER_SIZE, DMA_PERIPH_TO_MEMORY); /* DMA_PERIPH_TO_MEMORY */

#ifndef DMA_SUPPORT_DYN_CHANNEL_ALLOC
        // Enable DMA IRQ
        HAL_NVIC_SetPriority(cfg->dma_rx->dma_irq_prio, 0, 0);
        HAL_NVIC_EnableIRQ(cfg->dma_rx->dma_irq);
#endif /* !DMA_SUPPORT_DYN_CHANNEL_ALLOC */

        {
            // For RX DMA, also need to enable UART IRQ.
            __HAL_UART_ENABLE_IT(&UartHandle, UART_IT_IDLE); /* Set to generates interrupts when UART idle */
            HAL_NVIC_SetPriority(cfg->dma_rx->dma_irq_prio, 1, 0);
            HAL_NVIC_EnableIRQ(cfg->dma_rx->dma_irq);
        }
        /* Output a message on Hyperterminal using printf function */

        /* Output a message on Hyperterminal using hal function */
        uint8_t ptr[] = {'u', 'a', 'r', 't', '1', ' ', 'r', 'e', 'a', 'd', 'y', '\n'};
        int len = sizeof(ptr);
        HAL_UART_Transmit(&UartHandle, ptr, len, 0xFFFF);
    }
}
HAL_RAM_RET_CODE_SECT(hal_hw_usart_init,   void hal_hw_usart_init(void))
{
    rt_size_t obj_num = sizeof(uart_obj) / sizeof(struct sifli_uart);
    if (obj_num > 0)
    {
        sifli_uart_get_dma_config();
        HAL_UART_CONFIG(uart_config, obj_num, RT_SERIAL_DEFAULT_BAUDRATE);
    }
}
HAL_RAM_RET_CODE_SECT(hal_printf,    void hal_printf(char *fmt, ...))
{
    HAL_UART_Transmit(&UartHandle, fmt, 20, 0xFFFF);
}

2，相关hal初始uart的函数和打印函数以及调用的底层HAL文件都要放到RAM内运行，

就是这三个文件，HAL_RAM_RET_CODE_SECT(hal_hw_usart_init, void hal_hw_usart_init(void))这个函数都要调用到，需要放到RAM内，要添加在RW_IRAM_RET HPSYS_RETM_BASE HPSYS_RETM_SIZE {这个段内，如下图：