python - 通过 bash 向 pic18f2550 中继电路发送命令

Question

我有一个使用 pic18f2550 的 USB 中继电路，其供应商 ID:0461 和产品 ID:0020 我试图通过 python 通过 pyusb 与此设备通信，我可以连接设备但无法发送任何命令，总是出现忙错误。

如何在 ubuntu 中通过 bash 或 pyusb 向该电路发送命令？

我的python代码是

import usb.core
import usb.util
import struct
dev = usb.core.find(idVendor=0x0461, idProduct=0x0020)
if dev is None:
    raise ValueError('Device not found')
cfg = dev[0]
intf = cfg[(0,0)]

ep = usb.util.find_descriptor(
    intf,
    custom_match = \
    lambda e: \
        usb.util.endpoint_direction(e.bEndpointAddress) == \
        usb.util.ENDPOINT_OUT
)
assert ep is not None

buff = [0x80]
ep.write(buff)

我的 lsusb -v 详细信息；

Bus 003 Device 002: ID 0461:0020 Primax Electronics, Ltd 
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               1.10
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x0461 Primax Electronics, Ltd
  idProduct          0x0020 
  bcdDevice            1.00
  iManufacturer           1 SAC
  iProduct                2 ----arena----
  iSerial                 0 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           41
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         3 Human Interface Device
      bInterfaceSubClass      0 No Subclass
      bInterfaceProtocol      0 None
      iInterface              0 
        HID Device Descriptor:
          bLength                 9
          bDescriptorType        33
          bcdHID               1.00
          bCountryCode            0 Not supported
          bNumDescriptors         1
          bDescriptorType        34 Report
          wDescriptorLength      32
         Report Descriptors: 
           ** UNAVAILABLE **
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               1
Device Status:     0x0001
  Self Powered

Answer 1

尝试在/etc/udev/rules.d 文件中设置如下内容:

子系统 !="usb_device", 操作 !="add", GOTO="device_rules_end"
SYSFS{idVendor} =="1532", SYSFS{idProduct} =="0017", SYMLINK+="mydevice"
模式=“0666”，所有者=“”，组=“根”
LABEL="device_rules_end"