Recent Posts

1

USB / Re: Data from host to HID device

« Last post by Jan Axelson on October 11, 2018, 11:14:12 pm »

The attachment doesn't show the host's detecting, or arrival, of the device.

Yet the handles for write, likely using interrupt transfers, and for get report, likely using control transfers, appear to work.

It's hard to troubleshoot what's happening on the host side if you don't have the source code.

Can you access the device using my HID example code?

2

USB / Re: Data from host to HID device

« Last post by sd on October 09, 2018, 02:46:48 pm »

Hi Jan,

I'm trying to design a product. I've successfully achieved the upstream communication but there is some problem with the downstream communication. So could you elaborate more on the permissions part? Is it that the API is not permitting to send data or my BLE device isnt accepting data? I wish to send haptic data from host to BLE device.

3

USB / Re: Data from host to HID device

« Last post by Jan Axelson on October 08, 2018, 09:04:24 pm »

If the report descriptor includes at least one Output report, the host can use control transfers or interrupt transfers to send the reports to the HID.

Invalid handle suggests that the host was unable to attempt the transfer.

The error often has to do with permissions.

What are you trying to accomplish with the transfer? Is the device one you are designing or an off-the-shelf device?

4

USB / Re: Data from host to HID device

« Last post by sd on October 08, 2018, 07:33:41 pm »

Thank you Jan for your reply! I thought so that 'Set Report' might be using control transfer after reading your book! So now I will try to use a sniffer. But do you think host is able to send data to BLE device using "Write"?

5

USB / Re: Data from host to HID device

« Last post by Jan Axelson on October 04, 2018, 08:18:29 pm »

Assuming Set Report is attempting to use a control transfer, are you sure the device supports receiving reports via control transfers?

A protocol analyzer would show what is happening on the bus.

6

USB / Data from host to HID device

« Last post by sd on October 04, 2018, 06:25:57 pm »

Hello,

I am using the following HID descriptor for my BLE HID device. I also tried using the vendor defined page as mentioned in your book - USB Complete

Code: [Select]

0x05, 0x03, // USAGE_PAGE(VR Controls)
  0x09, 0x04, // USAGE (Glove)
  0xA1, 0x01, // COLLECTION (Application)
    0x85, 0x01, // REPORT_ID(1)
  0x09, 0x04, // USAGE (Glove)
  0x15, 0x00, // LOGICAL_MINIMUM(0)
  0x26, 0xFF, 0x00, // LOGICAL_MAXIMUM(255)
  0x75, 0x08, // REPORT_SIZE(8)
  0x95, 0x01, // REPORT_COUNT(1)
  0x81, 0x02, // INPUT(Data,Var,Abs)
  0x09, 0x04, // USAGE (Glove)
  0x15, 0x00, // LOGICAL_MINIMUM(0)
  0x26, 0xFF, 0x00, // LOGICAL_MAXIMUM(255)
  0x75, 0x08, // REPORT_SIZE(8)
  0x95, 0x01, // REPORT_COUNT(1)
  0x91, 0x02, // OUTPUT(Data,Var,Abs)
  0xC0 // END COLLECTION
I am using SimpleHIDWrite utility to send/receive data. Please check attachments which include the results for GetReport, SetReport & Write. So why isnt the SetReport getting the correct handle? I am not able to locate where the problem is exactly.

7

USB / Re: usb over Ethernet

« Last post by RebekaHumels on September 27, 2018, 05:04:30 am »

SpencerFrit78, Hello! With an external device, you will not get a good result, as they will not take a long distance. You need software like USB Network Gate. He will throw your device completely and correctly. On their website, you can see the specification completely. There are other analogs of software, you can compare with your requirements which one is better for you. Have fun!=)

8

USB / Re: HID - Sending OUT Report while IN Report is Waiting

« Last post by Jan Axelson on September 25, 2018, 05:39:05 am »

Due to buffering perhaps. You're right that sending OUT reports synchronously is a workaround since those generally don't result in a delay.

9

USB / Re: OBD2

« Last post by Jan Axelson on September 25, 2018, 05:33:56 am »

Thank you, will fix!

10

USB / Re: HID - Sending OUT Report while IN Report is Waiting

« Last post by Victor M on September 24, 2018, 03:21:24 pm »

WriteAsync always sends two reports at once?

Yes (and no), One other thing I noticed - when an OUT report is written (but not sent), and later an IN report is received, then the OUT report will be sent. So it's another way a 'stuck' OUT report gets 'unstuck', strange behavior.

Note: this occurs only when the 'FileFlagOverlapped' option is used and OUT reports are written asynchronous. I wanted to use overlapped IO so I could receive unsolicited IN reports as soon as they occur, and still be able to send OUT reports at any time. Sending OUT reports synchronously seems to be a solution.