lark1s_demo/stm32f4/src/rs485.c

#include "stm32f4xx_rcc.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_usart.h"
#include "stm32f4xx_dma.h"
#include "rs485.h"
#include "lark1s.h"
#include "dwin.h"

#define RS485_TX_STREAM   DMA1_Stream3
#define RS485_RX_STREAM   DMA1_Stream1
#define RS485_BUFF_TX_LEN (4096)
#define RS485_BUFF_RX_LEN (4096)
uint8_t rs485_buff_tx[RS485_BUFF_TX_LEN] __attribute__((aligned(16)));
uint8_t rs485_buff_rx[RS485_BUFF_RX_LEN] __attribute__((aligned(16)));
static int __attribute__((section(".bss_ccm"))) sm = 0;

char sn[16] __attribute__((section(".bss_ccm")));
struct lark1s_gas_info_s lark1s_gas_info __attribute__((section(".bss_ccm")));
struct lark1s_gas_cali_data_s lark1s_gas_cali_data __attribute__((section(".bss_ccm")));
struct lark1s_data_s lark1s_data __attribute__((section(".bss_ccm")));
struct lark1s_status_s lark1s_status __attribute__((section(".bss_ccm")));

extern uint32_t system_tick_cnt;

static void rs485_mode_tx(void)
{
    GPIO_SetBits(RS485_PORT, RS485_PIN_DIR);
}

static void rs485_mode_rx(void)
{
    GPIO_ResetBits(RS485_PORT, RS485_PIN_DIR);
}

void rs485_init(void)
{
    GPIO_InitTypeDef  GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;
    DMA_InitTypeDef  DMA_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);

    GPIO_InitStructure.GPIO_Pin = RS485_PIN_DIR,
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT,
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP,
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz,
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL,
    GPIO_Init(RS485_PORT, &GPIO_InitStructure);
    rs485_mode_tx();

    GPIO_PinAFConfig(RS485_PORT, GPIO_PinSource10, GPIO_AF_USART3);
    GPIO_PinAFConfig(RS485_PORT, GPIO_PinSource11, GPIO_AF_USART3);
    GPIO_InitStructure.GPIO_Pin = RS485_PIN_TX | RS485_PIN_RX;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(RS485_PORT, &GPIO_InitStructure);

    USART_DeInit(USART3);
    USART_OverSampling8Cmd(USART3, ENABLE);
    USART_InitStructure.USART_BaudRate = RS485_BAUDRATE;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_Parity = USART_Parity_No;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USART3, &USART_InitStructure);
    USART_DMACmd(USART3, USART_DMAReq_Tx, ENABLE);
    USART_DMACmd(USART3, USART_DMAReq_Rx, ENABLE);
    USART_Cmd(USART3, ENABLE);

    DMA_InitStructure.DMA_BufferSize = RS485_BUFF_TX_LEN;
    DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
    DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
    DMA_InitStructure.DMA_PeripheralBaseAddr =(uint32_t)(&(USART3->DR));
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_Priority = DMA_Priority_Low;
    DMA_InitStructure.DMA_Channel = DMA_Channel_4;
    DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)rs485_buff_tx;
    DMA_Init(RS485_TX_STREAM, &DMA_InitStructure);
    /* Configure DMA controller to manage USART RX request */ 
    DMA_InitStructure.DMA_BufferSize = RS485_BUFF_RX_LEN;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)rs485_buff_rx;
    DMA_Init(RS485_RX_STREAM, &DMA_InitStructure);
    /* Configure interrupt for USART3 RX */
    NVIC_InitStructure.NVIC_IRQChannel = USART3_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 12;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
    USART_ITConfig(USART3, USART_IT_IDLE, ENABLE);
    USART_ITConfig(USART3, USART_IT_TC, ENABLE);
    /* clear IT flag */
    USART_GetITStatus(USART3, USART_IT_IDLE);
    USART_ReceiveData(USART3);
    USART_ClearITPendingBit(USART3, USART_IT_IDLE);
    USART_ClearITPendingBit(USART3, USART_IT_TC);

    // rs485_send(15);
}

void rs485_send(uint16_t len)
{
    rs485_mode_tx();
    DMA_SetCurrDataCounter(RS485_TX_STREAM, len);
    DMA_Cmd(RS485_TX_STREAM, ENABLE);
}

void rs485_state_machine_tx(void)
{
    int len;

    switch (sm) {
        case 0: len = lark1s_req_sn(rs485_buff_tx); break;
        case 1: len = lark1s_req_gas3_info(rs485_buff_tx); break;
        case 2: len = lark1s_req_gas3_cali_data(rs485_buff_tx); break;
        case 3: len = lark1s_req_data(rs485_buff_tx); break;
        case 4: len = lark1s_req_status(rs485_buff_tx); break;
        default: len = 0; break;
    }
    rs485_send((uint16_t)len);
}

void rs485_state_machine_rx(int len)
{
    int ret = LARK1S_PARSE_OK;

    switch (sm) {
        case 0: ret = lark1s_parse_sn(rs485_buff_rx, len, sn); break;
        case 1: ret = lark1s_parse_gas3_info(rs485_buff_rx, len, &lark1s_gas_info); break;
        case 2: ret = lark1s_parse_gas3_cali_data(rs485_buff_rx, len, &lark1s_gas_cali_data); break;
        case 3: ret = lark1s_parse_data(rs485_buff_rx, len, &lark1s_data); break;
        case 4: ret = lark1s_parse_status(rs485_buff_rx, len, &lark1s_status); break;
        default: break;
    }
    if (ret) {
        return;
    }
    sm++;
    if (sm > 4) {
        sm = 0;
    }
}

void rs485_loop(void)
{
    static uint32_t ms = 0;

    if (system_tick_cnt < (ms + 200)) {
        return;
    }
    ms = system_tick_cnt;
    rs485_state_machine_tx();
}

void USART3_IRQHandler(void)
{
    uint16_t len;

    if (USART_GetITStatus(USART3, USART_IT_TC) != RESET)
    {
        USART_ClearITPendingBit(USART3, USART_IT_TC);
        DMA_ClearFlag(RS485_TX_STREAM, DMA_FLAG_TCIF3 | DMA_FLAG_HTIF3 | DMA_FLAG_TEIF3 | DMA_FLAG_DMEIF3 | DMA_FLAG_FEIF3);
        DMA_Cmd(RS485_TX_STREAM, DISABLE);
        /* after tx complete, config rx */
        USART_ReceiveData(USART3);
        USART_ClearITPendingBit(USART3, USART_IT_IDLE);
        DMA_SetCurrDataCounter(RS485_RX_STREAM, RS485_BUFF_RX_LEN);
        DMA_Cmd(RS485_RX_STREAM, ENABLE);
        USART_ITConfig(USART3, USART_IT_IDLE, ENABLE);
        rs485_mode_rx();
    }
    if (USART_GetITStatus(USART3, USART_IT_IDLE) != RESET) {
        USART_ITConfig(USART3, USART_IT_IDLE, DISABLE);
        USART_ReceiveData(USART3);
        USART_ClearITPendingBit(USART3, USART_IT_IDLE);
        DMA_Cmd(RS485_RX_STREAM, DISABLE);
        DMA_ClearFlag(RS485_RX_STREAM, DMA_FLAG_TCIF1 | DMA_FLAG_HTIF1 | DMA_FLAG_TEIF1 | DMA_FLAG_DMEIF1 | DMA_FLAG_FEIF1);
        len = DMA_GetCurrDataCounter(RS485_RX_STREAM);
        len = RS485_BUFF_RX_LEN - len;
        rs485_state_machine_rx((uint16_t)len);
    }
}