I'm new to USB HID programming and unsure whether I'm misunderstanding the device documentation or just going about this incorrectly.
I have a touch screen that I've successfully run the python test_hidwrap.py against. After reviewing the HID class documentation and the device documentation (http://home.eeti.com.tw/web20/drivers/Software%20Programming%20Guide_%20v1.5.pdf ), I'm fairly certain I should be sending a diagnostics packet using set_output_report. The trouble is that every path I try results in a broken pipe error. I've gathered that the path values ending in 0x00000000 are not complete paths and possibly additional bytes for neighboring paths? Looking through the archives, it seems like others have had a similar problem to the one I'm having, but I've been unable to extract a solution from these earlier posts. Any thoughts would be greatly appreciated! Thanks. ==> relevant python code: iface = hidwrap.Interface(vendor_id=0xeef, product_id=0x0001) iface.write_identification(sys.stdout) iface.dump_tree(sys.stdout) paths=[ [0x00010001,0x00010001,0x00010030], [0x00010001,0x00010001,0x00010031], [0x000d0004,0x000d0020,0x000d0042], [0x000d0004,0x000d0020,0x000d0032], [0x000d0004,0x000d0020,0x00010030], [0x000d0004,0x000d0020,0x00010031]] for path in paths: try: bytes = struct.pack('3b',0x0A,0x31,0x41) print 'Sending buffer of size %i to screen: %s' % (len(bytes), repr(bytes)) iface.set_output_report(path, bytes) except: print "%s: %s" % (sys.exc_info()[0], sys.exc_info()[1]) ==> code output: NOTICE: hid_init(): libhid 0.2.17 is being initialized. <snip> parse tree of HIDInterface 001/010[0]: path: 0x00010001.0x00010001.0x00000000; type: 0x80 path: 0x00010001.0x00010001.0x00000000; type: 0x80 path: 0x00010001.0x00010001.0x00000000; type: 0x80 path: 0x00010001.0x00010001.0x00010030; type: 0x80 path: 0x00010001.0x00010001.0x00010031; type: 0x80 path: 0x000d0004.0x000d0020.0x000d0042; type: 0x80 path: 0x000d0004.0x000d0020.0x000d0032; type: 0x80 path: 0x000d0004.0x000d0020.0x00000000; type: 0x80 path: 0x000d0004.0x000d0020.0x00000000; type: 0x80 path: 0x000d0004.0x000d0020.0x00000000; type: 0x80 path: 0x000d0004.0x000d0020.0x00000000; type: 0x80 path: 0x000d0004.0x000d0020.0x00000000; type: 0x80 path: 0x000d0004.0x000d0020.0x00000000; type: 0x80 path: 0x000d0004.0x000d0020.0x00010030; type: 0x80 path: 0x000d0004.0x000d0020.0x00010031; type: 0x80 TRACE: hid_reset_parser(): resetting the HID parser for USB device 001/010[0]... Sending buffer of size 3 to screen: '\n1A' TRACE: hid_set_output_report(): looking up report ID... TRACE: hid_prepare_parse_path(): preparing search path of depth 3 for parse tree of USB device 001/010[0]... TRACE: hid_prepare_parse_path(): search path prepared for parse tree of USB device 001/010[0]. TRACE: hid_format_path(): formatting device path... WARNING: hid_find_object(): can't find requested item 0x00010001.0x00010001.0x00010030 of USB device 001/010[0]. TRACE: hid_set_output_report(): sending report ID 0x00 (length: 3) to USB device 001/010[0]... WARNING: hid_set_output_report(): failed to send report to USB device 001/010[0]:error sending control message: Broken pipe. hidwrap.HIDError: (19, 'set_output_report: libhid: failed to set report') ==> lsusb -d 0eef:0001 -vvv Bus 001 Device 006: ID 0eef:0001 D-WAV Scientific Co., Ltd eGalax TouchScreen Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x0eef D-WAV Scientific Co., Ltd idProduct 0x0001 eGalax TouchScreen bcdDevice 2.00 iManufacturer 1 eGalax Inc. iProduct 2 USB TouchController iSerial 0 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 34 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 1 eGalax Inc. bmAttributes 0xa0 Remote Wakeup MaxPower 100mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Devices 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 141 Report Descriptor: (length is 141) Item(Global): Usage Page, data= [ 0x01 ] 1 Generic Desktop Controls Item(Local ): Usage, data= [ 0x01 ] 1 Pointer Item(Main ): Collection, data= [ 0x01 ] 1 Application Item(Global): Report ID, data= [ 0x01 ] 1 Item(Local ): Usage, data= [ 0x01 ] 1 Pointer Item(Main ): Collection, data= [ 0x00 ] 0 Physical Item(Global): Usage Page, data= [ 0x09 ] 9 Buttons Item(Local ): Usage Minimum, data= [ 0x01 ] 1 Button 1 (Primary) Item(Local ): Usage Maximum, data= [ 0x02 ] 2 Button 2 (Secondary) Item(Global): Logical Minimum, data= [ 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0x01 ] 1 Item(Global): Report Count, data= [ 0x02 ] 2 Item(Global): Report Size, data= [ 0x01 ] 1 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Report Count, data= [ 0x01 ] 1 Item(Global): Report Size, data= [ 0x06 ] 6 Item(Main ): Input, data= [ 0x01 ] 1 Constant Array Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Usage Page, data= [ 0x01 ] 1 Generic Desktop Controls Item(Local ): Usage, data= [ 0x30 ] 48 Direction-X Item(Local ): Usage, data= [ 0x31 ] 49 Direction-Y Item(Global): Logical Minimum, data= [ 0x2a 0x00 ] 42 Item(Global): Logical Maximum, data= [ 0xbd 0x07 ] 1981 Item(Global): Physical Minimum, data= [ 0x00 0x00 ] 0 Item(Global): Physical Maximum, data= [ 0xff 0x0f ] 4095 Item(Global): Unit, data= [ 0x00 0x00 ] 0 Item(Global): Report Size, data= [ 0x10 ] 16 Item(Global): Report Count, data= [ 0x02 ] 2 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Main ): End Collection, data=none Item(Main ): End Collection, data=none Item(Global): Usage Page, data= [ 0x0d ] 13 Digitizer Item(Local ): Usage, data= [ 0x04 ] 4 Touch Screen Item(Main ): Collection, data= [ 0x01 ] 1 Application Item(Global): Report ID, data= [ 0x02 ] 2 Item(Local ): Usage, data= [ 0x20 ] 32 Stylus Item(Main ): Collection, data= [ 0x00 ] 0 Physical Item(Local ): Usage, data= [ 0x42 ] 66 Tip Switch Item(Local ): Usage, data= [ 0x32 ] 50 In Range Item(Global): Logical Minimum, data= [ 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0x01 ] 1 Item(Global): Report Count, data= [ 0x02 ] 2 Item(Global): Report Size, data= [ 0x01 ] 1 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Report Count, data= [ 0x06 ] 6 Item(Global): Report Size, data= [ 0x01 ] 1 Item(Main ): Input, data= [ 0x03 ] 3 Constant Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Usage Page, data= [ 0x01 ] 1 Generic Desktop Controls Item(Local ): Usage, data= [ 0x30 ] 48 Direction-X Item(Global): Report Size, data= [ 0x10 ] 16 Item(Global): Report Count, data= [ 0x01 ] 1 Item(Global): Push, data=none Item(Global): Unit Exponent, data= [ 0x0d ] 13 Item(Global): Unit, data= [ 0x33 ] 51 Item(Global): Physical Minimum, data= [ 0x00 0x00 ] 0 Item(Global): Physical Maximum, data= [ 0x99 0x28 ] 10393 Item(Global): Logical Minimum, data= [ 0x00 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0xff 0x0f ] 4095 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Local ): Usage, data= [ 0x31 ] 49 Direction-Y Item(Global): Logical Minimum, data= [ 0x00 0x00 ] 0 Item(Global): Logical Maximum, data= [ 0xff 0x0f ] 4095 Item(Global): Physical Minimum, data= [ 0x00 0x00 ] 0 Item(Global): Physical Maximum, data= [ 0xaf 0x19 ] 6575 Item(Main ): Input, data= [ 0x02 ] 2 Data Variable Absolute No_Wrap Linear Preferred_State No_Null_Position Non_Volatile Bitfield Item(Global): Pop, data=none Item(Main ): End Collection, data=none Item(Main ): End Collection, data=none Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0008 1x 8 bytes bInterval 3 _______________________________________________ libhid-discuss mailing list [email protected] http://lists.alioth.debian.org/mailman/listinfo/libhid-discuss http://libhid.alioth.debian.org/
