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Hi,<br>
<br>
In answer to your question - wDescriptorLength 769<br>
<br>
The output of 'lsbusb -v' reports the following for the <b>newer</b>
Power Shield Defender:<br>
<br>
<blockquote type="cite">Bus 001 Device 005: ID 0665:5161 Cypress
Semiconductor USB to Serial<br>
Device Descriptor:<br>
bLength 18<br>
bDescriptorType 1<br>
bcdUSB 2.00<br>
bDeviceClass 0 <br>
bDeviceSubClass 0 <br>
bDeviceProtocol 0 <br>
bMaxPacketSize0 8<br>
idVendor 0x0665 Cypress Semiconductor<br>
idProduct 0x5161 USB to Serial<br>
bcdDevice 0.02<br>
iManufacturer 3 HID UPS<br>
iProduct 1 HID UPS<br>
iSerial 5 HID UPS<br>
bNumConfigurations 1<br>
Configuration Descriptor:<br>
bLength 9<br>
bDescriptorType 2<br>
wTotalLength 0x003b<br>
bNumInterfaces 2<br>
bConfigurationValue 1<br>
iConfiguration 0 <br>
bmAttributes 0xa0<br>
(Bus Powered)<br>
Remote Wakeup<br>
MaxPower 100mA<br>
Interface Descriptor:<br>
bLength 9<br>
bDescriptorType 4<br>
bInterfaceNumber 0<br>
bAlternateSetting 0<br>
bNumEndpoints 1<br>
bInterfaceClass 3 Human Interface Device<br>
bInterfaceSubClass 0 <br>
bInterfaceProtocol 0 <br>
iInterface 0 <br>
HID Device Descriptor:<br>
bLength 9<br>
bDescriptorType 33<br>
bcdHID 1.10<br>
bCountryCode 0 Not supported<br>
bNumDescriptors 1<br>
bDescriptorType 34 Report<br>
wDescriptorLength 27<br>
Report Descriptors: <br>
** UNAVAILABLE **<br>
Endpoint Descriptor:<br>
bLength 7<br>
bDescriptorType 5<br>
bEndpointAddress 0x81 EP 1 IN<br>
bmAttributes 3<br>
Transfer Type Interrupt<br>
Synch Type None<br>
Usage Type Data<br>
wMaxPacketSize 0x0008 1x 8 bytes<br>
bInterval 255<br>
Interface Descriptor:<br>
bLength 9<br>
bDescriptorType 4<br>
bInterfaceNumber 1<br>
bAlternateSetting 0<br>
bNumEndpoints 1<br>
bInterfaceClass 3 Human Interface Device<br>
bInterfaceSubClass 0 <br>
bInterfaceProtocol 0 <br>
iInterface 0 <br>
HID Device Descriptor:<br>
bLength 9<br>
bDescriptorType 33<br>
bcdHID 1.10<br>
bCountryCode 0 Not supported<br>
bNumDescriptors 1<br>
bDescriptorType 34 Report<br>
wDescriptorLength 769<br>
Report Descriptors: <br>
** UNAVAILABLE **<br>
Endpoint Descriptor:<br>
bLength 7<br>
bDescriptorType 5<br>
bEndpointAddress 0x82 EP 2 IN<br>
bmAttributes 3<br>
Transfer Type Interrupt<br>
Synch Type None<br>
Usage Type Data<br>
wMaxPacketSize 0x0008 1x 8 bytes<br>
bInterval 255<br>
can't get device qualifier: Resource temporarily unavailable<br>
can't get debug descriptor: Resource temporarily unavailable<br>
Device Status: 0x0002<br>
(Bus Powered)<br>
Remote Wakeup Enabled<br>
</blockquote>
<br>
<br>
<div class="moz-cite-prefix">On 7/3/20 23:43:05, Charles Lepple
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:F648DD6B-3320-424F-9707-A0812B3C67C4@gmail.com">
<pre class="moz-quote-pre" wrap="">On Mar 7, 2020, at 2:02 AM, HILL Walter <a class="moz-txt-link-rfc2396E" href="mailto:hill@ieee.org"><hill@ieee.org></a> wrote:
</pre>
<blockquote type="cite">
<pre class="moz-quote-pre" wrap="">
idVendor 0x0665 Cypress Semiconductor
idProduct 0x5161 USB to Serial
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">[...]
</pre>
<blockquote type="cite">
<pre class="moz-quote-pre" wrap="">N.B. the Product ID and Vendor ID are unchanged between the two models
despite the fact that they function and operate quite differently.
</pre>
</blockquote>
<pre class="moz-quote-pre" wrap="">Thanks for the information - sorry to hear you are dealing with this sort of "truth-in-labeling" issue on top of the instability of the old model.
Further down in the lsusb output should be some information about the HID interface. A good distinguishing factor between Power Device Class (PDC) HID devices and simpler serial-over-HID devices is the size of the HID descriptor. What does the newer model show for wDescriptorLength? Here's an example for an APC:
Bus 006 Device 002: ID 051d:0003 American Power Conversion UPS
Device Descriptor:
[...]
bNumConfigurations 1
Configuration Descriptor:
[...]
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 33 US
bNumDescriptors 1
bDescriptorType 34 Report
wDescriptorLength 515
</pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
,-_|\ Walter HILL
/ \ email: hill(at)ieee(dot)org
\_,-._/
v </pre>
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