for 循环中的 Pyserial 对象

Question

我用这个方法打开了4个串口：

ComPorts = ['com11','com13','com7','com19']
stimeout = 0.000120   ## 120 us character timeout
baud = 115200 
serList = {}
set_key = 0x0E 
keyList = [0,0,0,0,0,0,0,0,0]

for idx,com in enumerate(ComPorts):  ## open up the COM ports
    serList[idx] = serial.Serial(com,baud,timeout=stimeout)

我想向所有端口写入一条通用消息 - 这失败了：

for ser in serList:  
    SER_tx_command(ser,set_key,keyList) # send'

但这行得通（少 pythonic）：

for idx in range(len(ComPorts)): 
    SER_tx_command(serList[idx],set_key,keyList) # send

在这个常用函数中出现错误：

def SER_tx_command(ser,cmd,payload):
    length = len(payload)+4;
    cksum = (0x01 + length + cmd)&0x00FF
    msg = [0x01,length,cmd]
    if (length > 4):
        for val in payload:
            cksum = (cksum+val)&0x00FF
            msg.extend([val])
    msg.extend([cksum])
    for val in msg:
        ser.write(chr(val))  ###  ERROR HERE  ###

错误信息：

Traceback (most recent call last):
  File "packet_test02.py", line 468, in <module>
    update_key(key_jump)
  File "packet_test02.py", line 149, in update_key
    SER_tx_command(ser,set_key,keyList) # send the packet msg
  File "packet_test02.py", line 28, in SER_tx_command
    ser.write(chr(val))
    AttributeError: 'int' object has no attribute 'write'

如何让循环遍历串口对象？
还是 python 不可能，我必须使用索引迭代器方法？

Answer 1

serList 是 dict 而不是 list 并且迭代 dict 会迭代它的键。在您的例子中，键是 enumerate 中的整数索引。您可以改为迭代它的值（并重命名变量以减少混淆）

for ser in serDict.values():  
    SER_tx_command(ser, set_key, keyList) # send'

或使用 list 而不是 dict

ComPorts = ['com11','com13','com7','com19']
stimeout = 0.000120   ## 120 us character timeout
baud = 115200 
set_key = 0x0E 
keyList = [0,0,0,0,0,0,0,0,0]

serList = [serial.Serial(com,baud,timeout=stimeout) for com in ComPorts]  ## 
for ser in serList:  
    SER_tx_command(ser, set_key, keyList) # send'

Answer 2

for ser in serList:

遍历 serList 字典中的键。在您的情况下，键是整数，而不是 Serial 对象。

尝试：

for ser in serList:  
    SER_tx_command(serList[ser],set_key,keyList) # send'

for 循环中的 Pyserial 对象

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