fix: 串口获取档位

entry/src/main/ets/utils/SerialPort.ets

@@ -3,6 +3,9 @@ import HiSerialSDK from '@ohos.hiserialsdk';
 import { SerialPortTag } from '../config';
 
 // 打开串口工具
+/*
+  * @param serialPort 串口名称
+ */
 export const OpenSerialPort = (serialPort: string) => {
   return new Promise<number>((resolve, reject) => {
     testNapi.SerialOpenAsync(serialPort, (value: number) => {
@@ -17,6 +20,11 @@ export const OpenSerialPort = (serialPort: string) => {
 }
 
 //初始化串口数据
+/*
+  * @param fd 串口文件描述符
+  * @param speed 波特率
+  * @returns Promise<boolean> 成功返回true，失败返回false
+ */
 export const InitSerialPortData =
   async (fd: number, speed: number) => {
     return new Promise<boolean>((resolve, reject) => {
@@ -35,6 +43,11 @@ export const InitSerialPortData =
   }
 
 //发送数据
+/*
+  * @param fd 串口文件描述符
+  * @param data 要发送的数据数组
+  * @returns Promise<number> 成功返回发送的字节数，失败返回-1
+ */
 export const SendSerialPortData = (fd: number, data: number[]) => {
   console.log(SerialPortTag, "wzj-----发送数据")
   return new Promise<number>((resolve, reject) => {
@@ -49,6 +62,11 @@ export const SendSerialPortData = (fd: number, data: number[]) => {
 }
 
 // 接受数据
+/*
+  * @param fd 串口文件描述符
+  * @param timeout 超时时间，单位毫秒
+  * @returns Promise<HiSerialSDK.receiveInfo> 成功返回接收到的数据，失败返回-1
+ */
 export const ReceiveSerialPortData = (fd: number, timeout: number,) => {
   console.log(SerialPortTag, "wzj-----接受数据")
   return new Promise<HiSerialSDK.receiveInfo>((resolve) => {

entry/src/main/ets/utils/business/SerialPortService.ets

@@ -0,0 +1,72 @@
+// 串口业务逻辑
+
+import {
+  CancelReceiveSerialPortData,
+  InitSerialPortData,
+  OpenSerialPort,
+  ReceiveSerialPortDataBySelf
+} from '../SerialPort';
+import Prompt from '@system.prompt';
+import { SerialPortTag } from '../../config';
+
+class serialPortService {
+  private fd: number = -1
+  private serialPort: string = "/dev/ttyS3"
+  // 波特率
+  private baudRate: string = "115200"
+  private events: Array<Function> = []
+  // 尝试次数
+  private tryCount: number = 0
+
+  async init() {
+    const res = await OpenSerialPort(this.serialPort)
+    if (res === -1) {
+      Prompt.showToast({
+        message: "串口打开失败"
+      })
+      //   失败了重试,最大次数为5次
+      this.tryCount++;
+      if (this.tryCount < 5) {
+        console.log(SerialPortTag, "串口打开失败,尝试第", this.tryCount, "次重试")
+        setTimeout(() => {
+          this.init();
+        }, 1000);
+        return;
+      } else {
+        console.error(SerialPortTag, "串口打开失败,重试次数已达上限")
+        return;
+      }
+    } else {
+      this.fd = res;
+    }
+  }
+
+  async canInit() {
+    if (this.fd !== -1) {
+      await InitSerialPortData(this.fd, Number(this.baudRate))
+      ReceiveSerialPortDataBySelf(this.fd, (res1: number, res2: number, res3: number[]) => {
+        this.events.forEach((callback) => {
+          callback(res3);
+        });
+      })
+    }
+  }
+
+  onMsg(callback: Function) {
+    if (this.events.indexOf(callback) === -1) {
+      this.events.push(callback);
+    }
+  }
+
+  async closed() {
+    const res = await CancelReceiveSerialPortData(this.fd);
+    this.events = [];
+    if (res) {
+      console.log(SerialPortTag, "串口关闭成功")
+    } else {
+      console.error(SerialPortTag, "串口关闭失败")
+    }
+  }
+}
+
+export const SerialPortService = new serialPortService();