search

signal11 / hidapi

A Simple library for communicating with USB and Bluetooth HID devices on Linux, Mac, and Windows.
http://www.signal11.us/oss/hidapi/
Other
2.46k stars 901 forks source link

Windows: hid_enumerate returns null when one of the connected devices is disconnected #221

Open ptkatch opened 9 years ago

ptkatch commented 9 years ago

It's somewhat similar to https://github.com/signal11/hidapi/issues/102.

Symptoms:

It's not easily reproducible - I can't recreate on my Windows 7 Pro 64-bit, but can on Windows 7 Enterprise 64-bit, 32-bit POSReady 7 (Windows 7 Embedded), 32-bit POSReady 2009 (XP Embedded). Mouse and keyboard don't seem to cause issue, only Magtek. Issue is present in hidapi.dll both from pre-built zip and built from Git.

Below is hidtest output on MS Windows POSReady 2009, Version 2.0, Service Pack 3

* Magtek is unplugged *

D:\hidapi>hidtest unable to open device

* Plug-in Magtek *

D:\hidapi>hidtest Device Found type: 046d c05a path: \?\hid#vid_046d&pid_c05a#6&327afb95&0&0000#{4d1e55b2-f16f-11cf-88cb-001 111000030} serial_number: Manufacturer: Logitech Product: USB Optical Mouse Release: 5400 Interface: -1

Device Found type: 0801 3004 path: \?\hid#vid_0801&pid_3004#7&2f6bc5fb&0&0000#{4d1e55b2-f16f-11cf-88cb-001 111000030} serial_number: 98C898A90508070D Manufacturer: MagTek, Inc. Product: IPAD PLUS EMV Release: 6 Interface: -1

Device Found type: 2911 1500 path: \?\hid#vid_2911&pid_1500#6&33c3f010&0&0000#{4d1e55b2-f16f-11cf-88cb-001 111000030} serial_number: Manufacturer: Product: Magnetic Stripe Card Reader Release: 540 Interface: -1

Device Found type: 2911 16a0 path: \?\hid#vid_2911&pid_16a0#6&1e4a343c&0&0000#{4d1e55b2-f16f-11cf-88cb-001 111000030} serial_number: 0000000001 Manufacturer: Product: USB TOUCH V39N Release: 0 Interface: -1

Device Found type: 413c 2107 path: \?\hid#vid_413c&pid_2107#7&2afb0898&0&0000#{4d1e55b2-f16f-11cf-88cb-001 111000030} serial_number: Manufacturer: Dell Product: Dell USB Entry Keyboard Release: 115 Interface: -1

unable to open device

D:\hidapi>

* Unplug Magtek *

D:\hidapi>hidtest unable to open device

DJChloe commented 8 years ago

A long time ago I developed a piece of software in windows for a Belkin left handle gaming device. It is still on sourceforge with sourcecode (wich is in Delphi ). The project was called Martini something The all detection chain and handling of hid devices is encapsulated in a reusable class and is very reliable. It is under gpl3 licence and the code can be reworked in C++. If you are interested you can download the source code, study it and reuse for Mixxx. http://sourceforge.net/projects/nostromon50onvi/

DJChloe commented 8 years ago

Direct link to source code http://sourceforge.net/projects/nostromon50onvi/files/NOVA%20Suite/NOVA%20Suite%20v1.2.0.0%20final/Nova_suite_v1200_src.zip

DJChloe commented 8 years ago

If I remember well, hid_enumerate had to be called twice (once for initialization, once to poll the device ) in order to be reliable

DJChloe commented 8 years ago

It was important to make the software "hot plug and play " friendly