Question

我用这种方法打开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)

我想向所有端口写一条公共消息 - 这失败了：

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

但这有效（不那么pythonic）：

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

这个常见功能给出错误：

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  ###

错误讯息：

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'

如何让循环迭代串口对象？
或者使用python是不可能的，我必须使用索引迭代器方法吗？

Answer 1

serList是dict而不是list并且迭代dict会迭代其键。在您的情况下，键是来自enumerate的整数索引。您可以改为迭代其值（并重命名该变量以减少其混淆）

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

或使用list代替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，而不是串行对象。

尝试：

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

for循环中的Pyserial对象

2 个答案: