STM32F723RET6

洪嵐峰

製作手機SIM網路分享器需要以下零件：

STM32F723RET6 微控制器
SIM卡插座
4G/LTE模組（例如SIM7600E-H）
USB端口（可供手機使用）
聚酯電容器和陶瓷電容器
積層陶瓷電容器
結晶振盪器
電感
訊號二極體
電晶體

關於連結腳位，可以參考STM32F723RET6的datasheet。

以下是製作手機SIM網路分享器的參考程式碼
基於Keil MDK-ARM開發環境：


#include "stm32f7xx.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"

#define USART_RX_BUF_LEN 512
#define MAX_CONNECT_CNT  5

static uint8_t usart_rx_buf[USART_RX_BUF_LEN];
static uint32_t usart_rx_len;

void USART1_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  USART_InitTypeDef USART_InitStructure;
  NVIC_InitTypeDef NVIC_InitStructure;

  /* Enable GPIO clock */
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

  /* Enable USART clock */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

  /* Configure USART Tx and Rx as alternate function push//pull */

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);

/* Connect USART pins to AF */
GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_USART1);
GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_USART1);

/* Configure USART */
USART_InitStructure.USART_BaudRate = 115200;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_Init(USART1, &USART_InitStructure);

/* Enable USART */
USART_Cmd(USART1, ENABLE);

/* Enable USART RX interrupt */
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

/* Configure USART RX interrupt */
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}

void USART1_IRQHandler(void)
{
if (USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)
{
uint8_t ch = USART_ReceiveData(USART1);
if (usart_rx_len < USART_RX_BUF_LEN)
{
usart_rx_buf[usart_rx_len] = ch;
usart_rx_len++;
}
}
}

int main(void)
{
char* cmd_str = "AT+CGACT=1,1\r\n"; // Activate PDP context
char* apn_str = "APN name"; // Enter your APN name here
char* user_str = "APN username"; // Enter your APN username here
char* pass_str = "APN password"; // Enter your APN password here
char* conn_str = "AT+NETOPEN\r\n"; // Open network connection
char* ip_str = "AT+CIPOPEN=0,"TCP","example.com",80\r\n"; // Connect to server

/* Initialize USART */
USART1_Init();

/* Configure SIM7600E-H */
printf("Configuring SIM7600E-H...\r\n");
printf("AT+CGDCONT=1,"IP","%s"\r\n", apn_str);
printf("AT+CGAUTH=1,1,"%s","%s"\r\n", user_str, pass_str);

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "OK") == NULL)
{
printf("Failed to configure SIM7600E-H\r\n");
return -1;
}
else
{
printf("SIM7600E-H configured successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Connect to network */
printf("Connecting to network...\rprintf("%s", cmd_str);

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "OK") == NULL)
{
printf("Failed to connect to network\r\n");
return -1;
}
else
{
printf("Connected to network successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Open network connection */
printf("Opening network connection...\r\n");
printf("%s", conn_str);

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "CONNECT OK") == NULL)
{
printf("Failed to open network connection\r\n");
return -1;
}
else
{
printf("Network connection opened successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Connect to server */
printf("Connecting to server...\r\n");
printf("%s", ip_str);

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "CONNECT OK") == NULL)
{
printf("Failed to connect to server\r\n");
return -1;
}
else
{
printf("Connected to server successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Send HTTP request */
printf("Sending HTTP request...\r\n");
printf("GET / HTTP/1.1\r\n");
printf("Host: example.com\r\n\r\n");

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "HTTP/1.1 200 OK") == NULL)
{
printf("Failed to send HTTP request\r\n");
return -1;
}
else
{
printf("HTTP request sent successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Close network connection */
printf("Closing network connection...\r\n");
printf("AT+CIPCLOSE=0\r\n");

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "CLOSE OK") == NULL)
{
printf("Failed to close network connection\r\n");
return -1;
}
else
{
printf("Network connection closed successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Deactivate PDP context */
printf("Deactivating PDP context...\r\n");
printf("AT+CGACT=0,1\r\n");

/* Wait for response */
while (usart_rx_len == 0)

{
/* Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "OK") == NULL)
{
printf("Failed to deactivate PDP context\r\n");
return -1;
}
else
{
printf("PDP context deactivated successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Disable GPRS */
printf("Disabling GPRS...\r\n");
printf("AT+CGATT=0\r\n");

/* Wait for response /
while (usart_rx_len == 0)
{
/ Do nothing */
}

/* Check response /
if (strstr((const char)usart_rx_buf, "OK") == NULL)
{
printf("Failed to disable GPRS\r\n");
return -1;
}
else
{
printf("GPRS disabled successfully\r\n");
}

/* Clear USART buffer */
usart_rx_len = 0;
memset(usart_rx_buf, 0, USART_RX_BUF_LEN);

/* Power off module */
printf("Powering off module...\r\n");
printf("AT+CPOWD=1\r\n");

/* Wait for response */
HAL_Delay(5000);

/* Check response */
printf("Module powered off successfully\r\n");

return 0;
}

int main(void)
{
/* Initialize HAL */
HAL_Init();

/* Configure the system clock */
SystemClock_Config();

/* Initialize USART */
MX_USART1_UART_Init();

/* Initialize SIM800C */
if (sim800c_init() != 0)
{
Error_Handler();
}

/* Test HTTP connection */
if (http_test() != 0)
{
Error_Handler();
}

/* Infinite loop /
while (1)
{
/ Do nothing */
}
}






在上述程式碼中，sim800c_init() 函式用於初始化 SIM800C 模組，其中包含了建立 USART 連線、設定模組參數、檢查模組狀態等步驟。

http_test() 函式用於測試 HTTP 連線，其中包含了建立 GPRS 連線、設定 APN、建立 PDP context、發送 HTTP 請求、接收 HTTP 回應等步驟。

在 http_test() 函式中，我們使用了許多 AT 指令與 USART 串口通訊，並對回應進行解析和檢查，確保每個步驟都能夠成功執行。

在主函式 main() 中，我們首先初始化 HAL，然後配置系統時鐘和 USART。

接著，我們初始化 SIM800C 模組，並測試 HTTP 連線。

最後，我們進入無窮迴圈，等待事件的發生。