黑松山资源网 Design By www.paidiu.com
这个属于我项目中一个函数,跟大家分享一下我的思路及最终实现
在编写串口通信工具中,需要实现一个函数,自动找到对应com 口,并且连接该com口,保证后续通信正常
作为初始化过程的一部分。
思路
在win 设备管理器中,经常会出现多个com 口,但并不是每个com 口都是目标设备所链接的。
尝试打开每个com 口,输入enter 按键, 正确的com 口,会有ack log 返回,表明通信 正常
否则,没有任何log 返回,则判断为非目标设备所连接的com 口。
实现
尝试去打开所有com 口,然后发送enter, 如果在一段时间内有返回值,检查com 口收到的字节数,如果非零,则表明找到了对应的com 口。
完整测试代码如下:
import serial import serial.tools.list_ports import threading import binascii import time from datetime import datetime # default value baunRate = 115200 is_read = False is_write = False write_buff = [] sys_buff = [] mSerial = None callback = None is_opened = 0 is_registed = 0 class SerialPort: def __init__(self,port,buand): self.port = serial.Serial(port,buand) self.port.close() if not self.port.isOpen(): self.port.open() #the index of data_bytes for read operation,私有属性 #only used in read lines self.__read_ptr = 0 self.__read_head = 0 #store all read bytes # used in read date, read lines self.__data_bytes = bytearray() def port_open(self): if not self.port.isOpen(): self.port.open() def port_close(self): self.port.close() def send(self): global is_write global write_buff while is_write: if len(write_buff): msg = write_buff.pop(0) msg = msg+"\n" cmd = msg.encode() try: self.port.write(cmd) except: write_buff.clear() is_write = False write_buff.clear() def read_data(self): global is_read global is_opened byte_cnt = 0 while is_read: try: count = self.port.inWaiting() if count > 0: rec_str = self.port.read(count) self.__data_bytes = self.__data_bytes+rec_str #print("receive:",rec_str.decode()) #print(rec_str) byte_cnt += count if not is_opened: is_opened = 1 #print("累计收到:",byte_cnt) #time.sleep(0.5) self.read_lines() except: deinit() #将当前所有的数据都读出,读取位置不变,每次读取指针依次移动,不漏数据, 读取行为一直在进行 def read_lines(self): #reset line_cnt = 0 data_len = len(self.__data_bytes) #print ("") #print ("begin: prt=:", self.__read_ptr, " head =", self.__read_head,"current len =",data_len) if self.__read_ptr >=data_len: return #get all lines in current data_bytes while(self.__read_ptr < data_len-1): if(self.__data_bytes[self.__read_ptr+1] == 0x0a and self.__data_bytes[self.__read_ptr] == 0x0d): tmp = bytearray() tmp = self.__data_bytes[self.__read_head:self.__read_ptr] try: line = tmp.decode() except: self.__read_head = self.__read_ptr + 2 self.__read_ptr = self.__read_head continue iprint(line) line_cnt += 1 self.__read_head = self.__read_ptr + 2 self.__read_ptr = self.__read_head else: self.__read_ptr = self.__read_ptr + 1 def auto_open_serial(): global baunRate global mSerial global callback global is_registed global is_opened #reset deinit() # 列出所有当前的com口 port_list = list(serial.tools.list_ports.comports()) port_list_name = [] #get all com if len(port_list) <= 0: iprint("the serial port can't find!") return False else: for itms in port_list: port_list_name.append(itms.device) #try open #print(port_list_name) for i in port_list_name: try: mSerial = SerialPort(i,baunRate) iprint("try open %s"%i) start_task() send("") #return True time.sleep(1) if is_opened: iprint("connect %s successfully"%i) return True else: deinit() if i == port_list_name[len(port_list_name)-1]: iprint("uart don't open") break continue except: iprint(" uart don't open") deinit() return False def deinit(): global mSerial global is_write global is_read global write_buff global is_opened if mSerial: mSerial.port_close() is_opened = 0 is_read = False is_write = False write_buff = [] mSerial = None time.sleep(1) def init(): global mSerial global callback global is_registed global is_opened global is_read global is_write #retry retry_time = 0 while not auto_open_serial(): if not is_opened: iprint("wait for uart connect, retry %s"%str(retry_time)) else: return True retry_time += 1 time.sleep(2) if retry_time == 10: iprint(" open uart fail") return False def send(msg): global mSerial global is_write global write_buff if is_write: write_buff.append(msg) def start_task(): global mSerial global is_write global is_read if mSerial: is_write = True t1 = threading.Thread (target=mSerial.send) t1.setDaemon (False) t1.start () is_read = True t2 = threading.Thread (target=mSerial.read_data) t2.setDaemon (False) t2.start () def iprint(msg): global callback global is_registed msg = "[Uart] "+str(msg) if is_registed: callback.append(msg) else: print(msg) def start_sys_cmd(): global is_registed if is_registed: t3 = threading.Thread (target=process_receive_sys_cmd) t3.setDaemon (False) t3.start() def process_receive_sys_cmd(): global sys_buff global is_registed global callback #print("process_receive_sys_cmd") while is_registed: #print ("wait,process_receive_sys_cmd") if len(sys_buff): #print ("receive,process_receive_sys_cmd") line = sys_buff.pop(0) if "init" in line: if is_opened and is_read and is_write: iprint("already open uart") break iprint("start init") init() if is_opened: break iprint("Eixt uart sys thread") def register_cback(list): global callback global is_registed callback = list is_registed = 1 def unregister_cback(): global callback callback.clear() if __name__ == '__main__': receive = [] register_cback(receive) sys_buff.append("init") start_sys_cmd() def process_receive_msg(): global receive while True: #print("wait") if len(receive): #print("receive") print(receive.pop(0)) t = threading.Thread(target=process_receive_msg) t.setDaemon(False) t.start()
黑松山资源网 Design By www.paidiu.com
广告合作:本站广告合作请联系QQ:858582 申请时备注:广告合作(否则不回)
免责声明:本站资源来自互联网收集,仅供用于学习和交流,请遵循相关法律法规,本站一切资源不代表本站立场,如有侵权、后门、不妥请联系本站删除!
免责声明:本站资源来自互联网收集,仅供用于学习和交流,请遵循相关法律法规,本站一切资源不代表本站立场,如有侵权、后门、不妥请联系本站删除!
黑松山资源网 Design By www.paidiu.com
暂无评论...
RTX 5090要首发 性能要翻倍!三星展示GDDR7显存
三星在GTC上展示了专为下一代游戏GPU设计的GDDR7内存。
首次推出的GDDR7内存模块密度为16GB,每个模块容量为2GB。其速度预设为32 Gbps(PAM3),但也可以降至28 Gbps,以提高产量和初始阶段的整体性能和成本效益。
据三星表示,GDDR7内存的能效将提高20%,同时工作电压仅为1.1V,低于标准的1.2V。通过采用更新的封装材料和优化的电路设计,使得在高速运行时的发热量降低,GDDR7的热阻比GDDR6降低了70%。
更新日志
2024年07月06日
2024年07月06日
- 孙露《不让我的眼泪陪我过夜》HQCDII 限量版 [WAV+CUE][517M]
- dnf巴卡尔武器怎么融合
- 魔兽世界wlk最强职业是什么 wlk最吃香最强职业推荐
- dnf巴卡尼单人和多人区别
- 群星《大热唱片DSD》APE+CUE
- 草蜢2012《软硬草蜢》3CD[WAV+CUE整轨]
- 雨林唱片发烧大碟-陈果《明知故犯HQCD》[WAV+CUE]
- 群星.2024-狐妖小红娘月红篇电视剧原声带【恒星引力】【FLAC分轨】
- 许美静.1998-好美静【上华】【WAV+CUE】
- 谭咏麟.1996-独一无二【宝丽金】【WAV+CUE】
- dnf平民怎么弄宠物
- dnf弓箭手职业
- dnf强化基础精通适合哪些职业
- V.A中国管弦乐纪念名盘《乡之音》FLAC
- [雨果]赵鹏《赵鹏·LPCD45》LPCD45[WAV+CUE]