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USB CDC descriptor problem

Hello.

First of all, I want to say that I don't know if this is the right forum to do the question, but after days searching in the web, reading papers and changing the code, I'll try to explain my dude here.

I'm programming a device, with a USB communication in order to communicate with PC. I use an ATmega1281 with MAX3420 as USB controller. I get the windows recognize the device as COM Port...but I can only send or only receive data. If I try to set number of endpoints to 2 in the Data Class Interface descriptor, windows return an error (code 10), and can't initialize the device.
Here I show the configuration descriptors I use. Thank you for your time in advance! and regards.

const unsigned char CD[]=
// CONFIGURATION Descriptor
{ 0x09,// bLength
0x02,// bDescriptorType = Config
67,0x00,// wTotalLength(L/H)
0x02,// bNumInterfaces = 2
0x01,// bConfigValue
0x00,// iConfiguration
0xC0,// bmAttributes. b7=1
0x32,// MaxPower is 100 ma

// INTERFACE Descriptor
0x09,// length = 9
0x04,// type = IF
0x00,// InterFace Number = 0
0x00,// bAlternate Setting
0x01,// bNum Endpoints = 1 IN
0x02,// bInterfaceClass = 2 Communication
0x02,// bInterfaceSubClass = 2
0x01,// bInterfaceProtocol =1 (SubClass ACM,V.25ter)
0x00,// iInterface
// Header Functional Descriptor (marks beginning of the concatenated set of Functional Descriptors)
0x05,// bFunctionLength, Descriptor size in bytes
0x24,// bDescriptorType, CS_INTERFACE
0x00,// bDescriptorSubtype, Header Functional Descriptor
0x10,0x01,// bcdCDC

// Abstract Control Management Functional Descriptor
0x04,// bDescriptorLength, Descriptor size in bytes
0x24,// bDescriptorType, CS_INTERFACE
0x02,// bDescriptorSubtype, ACM Functional Descriptor
0x06,// bmCapabilities

// Union Functional Descriptor
0x05,// bFunctionLength, Descriptor size in bytes
0x24,// bDescriptorType, CS_INTERFACE
0x06,// bDescriptorSubtype, Union Functional Descriptor
0x00,// bMasterInterface
0x01,// bSlaveInterface0

// Call Management Functional Descriptor
0x05,// bFunctionLength, Descriptor size in bytes
0x24,// bDescriptorType, CS_INTERFACE
0x01,// bDescriptorSubtype, Call Management Funct.Desc.
0x03,// bmCapabilities
0x01,// bDataInterface

// Endpoint Descriptor EP3-IN
0x07,// bLength
0x05,// bDescriptorType (Endpoint)
0x83,// bEndpointAddress (EP3 IN)
0x03,// bmAttributes (interrupt = 3)
0x40,0x00,// wMaxPacketSize
0x02,// bInterval, Maximum latency

// INTERFACE Descriptor
0x09,// length = 9
0x04,// type = IF
0x01,// InterFace Number = 1
0x00,// bAlternate Setting
0x01,// bNum Endpoints = 2 (IN&OUT)
0x0A,// bInterfaceClass = A (Data)
0x00,0x00,// bInterfaceSubClass, bInterfaceProtocol
0x00,// iInterface

// Endpoint Descriptor EP2-IN
0x07,// bLength
0x05,// bDescriptorType (Endpoint)
0x82,// bEndpointAddress (EP2-IN)
0x02,// bmAttributes (bulk = 2)
0x40,0x00,// wMaxPacketSize (64[0x40])
0x00,// bInterval

// Endpoint Descriptor EP1-OUT
0x07,// bLength
0x05,// bDescriptorType (Endpoint)
0x01,// bEndpointAddress (EP1-OUT)
0x02,// bmAttributes (bulk = 2)
0x40,0x00, // wMaxPacketSize (64[0x40])
0x00,// bInterval
};

Parents
  • I monitored my CDC implementation on a hardware bus analyzer.
    This is the result.

    CDC-ACM (port) enumeration sequence
    
    WinXP SP2, SP3
                            wValue  wIndex   wLen
    Bus Reset
    Get_Descriptor(DEVICE)  0x0100  0x0000  0x0040
    Bus Reset
    Set_Address               0002    0000    0000
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    0009
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0303    0409    00FF
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0302    0409    00FF
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0302    0409    00FF
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Set_Configuration         0001    0000    0000
    Get_Line_Coding           0000    0000    0007
    Set_Control_Line_State    0000    0000    0000
    IN transaction to the Interrupt IN EP
    
    
    Vista SP1
                            wValue  wIndex   wLen
    Bus Reset
    Get_Descriptor(DEVICE)  0x0100  0x0000  0x0040
    Bus Reset
    Set_Address               0002    0000    0000
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Get_Descriptor(STRING)    0303    0409    00FF
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0302    0409    00FF
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Set_Configuration         0001    0000    0000
    Get_Line_Coding           0000    0000    0007
    Set_Control_Line_State    0000    0000    0000
    IN transaction to the Interrupt IN EP
    

    Other than the device_qualifier (because of in-between hub),
    Frame No.9 and 10 are different from your observation.
    Your frame No.9 should be Get_Descriptor(DEVICE), with wLength =18 bytes,
    And No.10 Get_Descriptor(CONFIG) with wLength =255 bytes

    Tsuneo

Reply
  • I monitored my CDC implementation on a hardware bus analyzer.
    This is the result.

    CDC-ACM (port) enumeration sequence
    
    WinXP SP2, SP3
                            wValue  wIndex   wLen
    Bus Reset
    Get_Descriptor(DEVICE)  0x0100  0x0000  0x0040
    Bus Reset
    Set_Address               0002    0000    0000
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    0009
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0303    0409    00FF
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0302    0409    00FF
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0302    0409    00FF
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Set_Configuration         0001    0000    0000
    Get_Line_Coding           0000    0000    0007
    Set_Control_Line_State    0000    0000    0000
    IN transaction to the Interrupt IN EP
    
    
    Vista SP1
                            wValue  wIndex   wLen
    Bus Reset
    Get_Descriptor(DEVICE)  0x0100  0x0000  0x0040
    Bus Reset
    Set_Address               0002    0000    0000
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Get_Descriptor(STRING)    0303    0409    00FF
    Get_Descriptor(STRING)    0300    0000    00FF
    Get_Descriptor(STRING)    0302    0409    00FF
    Get_Descriptor(DEVICE)    0100    0000    0012
    Get_Descriptor(CONFIG)    0200    0000    00FF
    Set_Configuration         0001    0000    0000
    Get_Line_Coding           0000    0000    0007
    Set_Control_Line_State    0000    0000    0000
    IN transaction to the Interrupt IN EP
    

    Other than the device_qualifier (because of in-between hub),
    Frame No.9 and 10 are different from your observation.
    Your frame No.9 should be Get_Descriptor(DEVICE), with wLength =18 bytes,
    And No.10 Get_Descriptor(CONFIG) with wLength =255 bytes

    Tsuneo

Children
  • Hello, Tsuneo.

    I try to install USBlyzer in another computer with Vista Business, and it seems that works (in Vista Ultimate it doesn't work rigth, because any program that try to open the port tell that it can't be open or that is already used by another telephone program).

    I can see that when I try to send by EP2 IN (bulk tranfer) any data the analyzer notify:

    Type---Request--------------------Request Details
    URB----Bulk or Interrupt Transfer--4096
    URB----Bulk or Interrupt Transfer--0

    and after the second notification the Status=Unsucceful(Stall PID). Both IRP=84389C80H.

    If I run program step by step, it returns the same except for the second notify:

    Type---Request--------------------Request Details
    URB----Bulk or Interrupt Transfer--4096
    URB----Bulk or Interrupt Transfer--11

    and after the second notification the Status=Success(Success).

    When I look at request summary, I can see the following comments about the first bulk transfer:

    USB Bulk or Interrupt Transfer issued
    Device Object: USBPDO-7
    Driver Object: usbhub
    URB Function: URB_FUNCTION_BULK_OR_INTERRUPT_TRANSFER
    Endpoint 82h: 2 in, Bulk
    Buffer Length: 1000h (4096)

    The second bulk notification when return unsuccseful:

    URB Bulk or interrupt transfer failed
    all is the same except for.
    URB Status: USBD_STATUS_STALL_PID
    and there is no Buffer Length.

    The second bulk notification whem return success:

    USB Bulk or Interrupt Transfer succeeded
    all the same but,
    URB Status: USBD_STATUS_SUCCESS
    and,
    Bytes Received: 11

    I don't know why debugging step by step it return a different values, maybe is related with communications speed?

    Why after host return Bulk transfer succeeded don't let me start another bulk transfer?

    Should I notifify a new serial status?

    Now I will try to get enumeration frames in the USB analyzer. I don't know the reason why Vista send me different requests than you.

    Regards.

  • When the sniffer reports STALL on the bulk-IN EP, your firmware actually STALL the EP. I think it is a bug on the firmware.

    "maybe is related with communications speed?"
    "Should I notifify a new serial status?"

    The bulk IN and OUT transfers of CDC is affected neither by the baudrate setting (Set_Line_Coding) nor by the Serial_State notification over the interrupt IN EP. The bulk IN and OUT transfers are controlled independently following to the USB intrinsic NAK flow-control.

    Did you check your Frame No.9 and No.10 on the enumeration?

    Tsuneo

  • Hello.

    I check the frames with USb analyzer, and discover that were a problem with a configuration descriptor. Now I see that host don't ask me for a configuration descriptor of 160 Bytes, and it seems that there is no error in configuration descriptor.
    Anyway the behaviour of the device it's the same.
    Now, the frames I can see in the enumeration are:

     1.Get Device Descriptor   128  6  0  1  0  0 64  0
     Bus Reset
     2.Set Address              0   5  1  0  0  0 000 0
     3.Get Device Descriptor   128  6  0  1  0  0 018 0
     4.Get Configuration Des.  128  6  0  1  0  0 255 0
     5.Get String Descriptor   128  6  3  3  9  4 255 0
     6.Get String Descriptor   128  6  0  3  0  0 255 0
     7.Get String Descriptor   128  6  2  3  9  4 255 0
     8.Get Device Qualifier    128  6  0  6  0  0 010 0
     9.Get Device Descriptor   128  6  0  1  0  0 018 0
    10.Get Configuration Des.  128  6  0  1  0  0 009 1
    11.Get Line Coding         161 33  0  0  0  0 007 0
    12.Set Control Line State   33 34  0  0  0  0 000 0
    

    Frame Nº9 is Get Device Descriptor with length of 18, and the next Configuration descriptor with length of (109??). I thought this frame has a length of 19, and there was an error. Now I send all descriptors here and USB analyzer don't return an error.
    I don't understand why I only can send the first frame, and it don't works anymore...I see in the analyzer some frames OUT in EP 2, that is configured IN (and can't work as out), and is sent from host the following data:

    1B DF 08 0A 00 00 00 0E 05 20 01 00 00 00 58 13 00 00 5F 29
    

    These frames are not always identical, but are similar...

    Regards.

  • After spending a long time changing the code, I always get the same result:

    it seems that the device send the first frame by EP2 (IN Bulk) after connecting with serial port, the length and data sent is correct.

    After this frame, the 'response' is that the frame is 4096 Bytes length.

    The next operation device realices is to send a frame by EP3 (IN, Interrupt) (I don't know why, I don't try to send any frame by this EP, but the Serial State when the device connects to serial Port), but the status report tells me 'USBD_STATUS_BUFFER_OVERRRUN'.

    Finally, there appears another try of sending a frame by EP2 (IN, Bulk), but the status says: 'USBD_STATUS_STALL_PID'.

    I'm sure there are an error in the code, when I try to send the data by EP2, but I can't see it. I try to make a 'data toggle' in EP3 some times, and it works...for one time and no more (I suppose it was a set of circumstances, a simple coincidence), but it makes me think that I'm doing something wrong in the protocol sending data? (and the device is configurated correctly).

  • Well, finally the problem is solved!

    There was an error, after sending set_control_line_status by interrupt EP, device don't send a ZLP correctly due a firmaware error, it was all...uff...I almost go crazy :P.

    Thanks for your attention, speccially for Tsuneo.

    Regards.

  • Hi, i'm student in indonesia. i have a final project, i will develop some embedded system application that works with usb. after +-2 month i learning max3420, i still can't reply host OUT request. can you help me? can you send me your code?

    thanks a lot

    suriva (suriva.25 at gmail dot com)

  • I read your message, and I'll post the reply as soon as possible.

    Regards, RubeÂ'n.

  • This is exactly the same issue i am facing. You mention that you reply to SET_CONTROL_LINE_STATE setup command from the host using the interrupt endpoint (which is 3 IN in your case). What is the exact reply you post to host? Is it NETWORK_CONNECTION status?

    Also after you send the reply, you mention that a ZLP has to be sent. Is it from device to the host? Is it on control endpoint (EP 0 IN)?

    I am looking forward to the reply from you or Tsuneo. Thanks in advance.