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USB Host - Sending data to device



I’m trying to send data to a device but I get a System.Exception from GHIElectronics.NETMF.USBHost.dll :frowning:

The data to be sent is this one :

0000: 22 09 00 02 00 00 00 00 
bmRequestType: 22
  DIR: Host-To-Device
  TYPE: Class
  RECIPIENT: Endpoint
bRequest: 09  

TransferBuffer: 0x00000004 (4) length
0000: 80 00 00 01 

My code is this one :

OutputData[0] = 0x80;
            OutputData[1] = 0x00;
            OutputData[2] = 0x00;
            OutputData[3] = 0x01;
            _IF1018.SendSetupTransfer(0x22, 0x09, 0x0002, 0x0000, OutputData, 0, 4); 
            //_IF1018.SendSetupTransfer(0x22, 0x09, 0x00, 0x02, OutputData, 0, 4); 

None of this works…

What am I doing wrong ?

Any help would be welcome here.

Best regards,



This is little endian, you need to switch the bytes order:
_IF1018.SendSetupTransfer(0x22, 0x09, 0x0200, 0x0000, OutputData, 0, 4);


Doesn’t work either :frowning:

    #### Exception System.Exception - 0xffffffff (4) ####
    #### GHIElectronics.NETMF.USBHost.USBH_RawDevice::SendSetupTransfer [IP: 0000] ####
    #### FEZPhidgets.IF1018::Output [IP: 0038] ####
    #### MFConsoleApplication1.Program::Phidget1018_InputChange [IP: 003f] ####
    #### FEZPhidgets.IF1018::GetInputs [IP: 0055] ####
    #### FEZPhidgets.IF1018::_1018Thread [IP: 0083] ####
A first chance exception of type 'System.Exception' occurred in GHIElectronics.NETMF.USBHost.dll
An unhandled exception of type 'System.Exception' occurred in GHIElectronics.NETMF.USBHost.dll

If it can help, here’s the report from USBView :

Device Descriptor:
bcdUSB:             0x0110
bDeviceClass:         0x00
bDeviceSubClass:      0x00
bDeviceProtocol:      0x00
bMaxPacketSize0:      0x08 (8)
idVendor:           0x06C2
idProduct:          0x0045
bcdDevice:          0x081A
iManufacturer:        0x01
0x0409: "Phidgets Inc."
iProduct:             0x02
0x0409: "PhidgetInterfaceKit"
iSerialNumber:        0x03
bNumConfigurations:   0x01

ConnectionStatus: DeviceConnected
Current Config Value: 0x01
Device Bus Speed:     Low
Device Address:       0x02
Open Pipes:              1

Endpoint Descriptor:
bEndpointAddress:     0x81  IN
Transfer Type:   Interrupt
wMaxPacketSize:     0x0008 (8)
bInterval:            0x08

Configuration Descriptor:
wTotalLength:       0x0022
bNumInterfaces:       0x01
bConfigurationValue:  0x01
iConfiguration:       0x00
bmAttributes:         0x80 (Bus Powered )
MaxPower:             0xFA (500 Ma)

Interface Descriptor:
bInterfaceNumber:     0x00
bAlternateSetting:    0x00
bNumEndpoints:        0x01
bInterfaceClass:      0x03 (HID)
bInterfaceSubClass:   0x00
bInterfaceProtocol:   0x00
iInterface:           0x00

HID Descriptor:
bcdHID:             0x0110
bCountryCode:         0x00
bNumDescriptors:      0x01
bDescriptorType:      0x22
wDescriptorLength:  0x0020

Endpoint Descriptor:
bEndpointAddress:     0x81  IN
Transfer Type:   Interrupt
wMaxPacketSize:     0x0008 (8)
bInterval:            0x08

There’s nothing weird in this report, to me. Only one endpoint, only one pipe.

The USB Frame shown in my first post was captured by a sniffer. I know that this frame was the one I wanted to send because it is the only one that contains the value(s) that I know are being modified.
Here, the 0x80 in the transfer buffer represents a binary 10000000, which means that the Digital Output #7 is “on”, while the others are “off”.


I’ve just figured it out :slight_smile:

bmRequestType should be 0x21, not 0x22…

_IF1018.SendSetupTransfer(0x21, 0x09, 0x02, 0x00, OutputData, 0, 4);

Now it’s working almost like a charm :slight_smile:


Here’s a video showing the use of the digital outputs on the Phidgets 1018 board : (20 MB)

Setup :

  • the push button is on a digital input of the 1018
  • this button turns on a led on the 1018 and the one on the FEZ Domino
  • the LDR button on the FEZ Domino turns off both leds

With this driver, I can now easily add 8 digital IO and 8 analog inputs to the FEZ Domino :slight_smile:

Usage is very simple, as usual.
For example, this code snippet shows how to turn on Phidgets 1018 Digital Output 7 (and onboard led) when Digital Input 6 state changes (button pressed). The code is placed in the user supplied event handler.

static void Phidget1018_InputChange(object sender, Phidget1018InputChangeEventArgs e)
            if (e.Index == 6) { IF1018.Output(7, true); Led.Write(true); }


Thanks for all the efforts, looks great.

By the way, uploading the video to youtube makes it easier to users to watch instead of downloading 20MB :slight_smile: I may take your video and upload it, if that is okay with you.


[quote]I may take your video and upload it, if that is okay with you.[/quote] Yes you can :wink:


Project is updated with your video :slight_smile: