将hex转换为bytes

def get_head_bytes(data_len,type_name): header_bytes =b'' head_bytes = struct.pack('<H',43605) //将两个short转换为bytes header_bytes+=head_bytes token = bytes.fromhex('10') //将hex转换为bytes header_bytes+=token wLen = struct.pack('<H',data_len) header_bytes+=wLen eStation =bytes.fromhex('01') header_bytes+=eStation ebedno =bytes.fromhex('01') header_bytes+=ebedno IFrameNo = struct.pack('<I',1) header_bytes +=IFrameNo eFilter = bytes.fromhex('01') header_bytes +=eFilter wGain = struct.pack('<H',400) header_bytes +=wGain if type_name=='I': eLead = bytes.fromhex('12') elif type_name=='II': eLead =bytes.fromhex('13') elif type_name=='V1': eLead = bytes.fromhex('14') elif type_name=='V5': eLead = bytes.fromhex('15') header_bytes +=eLead wSamp = struct.pack('<H',250) header_bytes +=wSamp tail1 = bytes.fromhex('FF') header_bytes +=tail1 tail2 = bytes.fromhex('FF') header_bytes +=tail2 return header_bytes