dynamic product ids?

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ulao

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Aug 20, 2021, 8:23:48 PMAug 20
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How can I use product ID dynamically?

.VendorID is read only..

I'm well aware that USB is static, but I set a product ID based on eeprom at initialization. I need to be able to set this dynamically.


ulao

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Aug 21, 2021, 1:14:10 PMAug 21
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so figured most of it out (I think) but the device does not enumerate so I'm missing something.

 

I swapped theses guys out

     #define USE_RAM_DESCRIPTORS
//          #define USE_FLASH_DESCRIPTORS

 

then change

 const USB_Descriptor_Device_t PROGMEM  DeviceDescriptor

ro

  USB_Descriptor_Device_t  DeviceDescriptor  and defined it in the h file.

 

and that allows this

DeviceDescriptor.ProductID = 0x16D0 ;

 

but it does not enumerate.

Dean Camera

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Aug 23, 2021, 4:36:10 AMAug 23
to lufa-s...@googlegroups.com, ulao

That's correct; you need to enable USE_RAM_DESCRIPTORS, as well as remove the `const` and `PROGMEM` qualifiers on all the descriptors (if you want to retain some of them in Flash, you can undefine all the `USE_*_DESCRIPTORS` options and instead indicate the memory space in the `CALLBACK_USB_GetDescriptor` descriptor callback via the additional output parameter that will be enabled.

The last step for using all-RAM descriptors, which I think you may have missed, is to remove the `pgm_read_byte()` calls inside `CALLBACK_USB_GetDescriptor`. Currently it will still be trying to read the descriptor length from flash, rather than RAM. Just replace the `pgm_read_byte(&SomeDescriptor.Header.Size);` instances with plain `SomeDescriptor.Header.Size;`.

Cheers,

- Dean

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ulao

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Aug 23, 2021, 1:30:16 PMAug 23
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few paths still unclear for me I'm afraid but I made these changes.

switch (DescriptorType)
    {
        case DTYPE_Device:
            Address = &DeviceDescriptor;
            Size    = sizeof(USB_Descriptor_Configuration_t);
            break;
        case DTYPE_Configuration:
            Address = &ConfigurationDescriptor;
            Size    = sizeof(ConfigurationDescriptor);
            break;
        case DTYPE_String:
            switch (DescriptorNumber)
            {
                case 0x00:
                    Address = &LanguageString;
                    Size    = LanguageString.Header.Size;//pgm_read_byte(&LanguageString.Header.Size);
                    break;
                case 0x01:
                    Address = &ManufacturerString;
                    Size    = ManufacturerString.Header.Size;//pgm_read_byte(&ManufacturerString.Header.Size);
                    break;
                case 0x02://todo no need, it does not show up anyways.
                    Address = &ProductString;
                    Size    = ProductString.Header.Size;
                    break;
                case 0x03:
                    Address = &VersionString;
                    Size    = VersionString.Header.Size;//pgm_read_byte(&VersionString.Header.Size);
                    break;
            }

            break;
        case DTYPE_HID:
            Address = &ConfigurationDescriptor.HID_JoystickHID;
            Size    = sizeof(USB_HID_Descriptor_HID_t);
            break;
        case DTYPE_Report:
            Address = &JoystickReport;
            Size    = sizeof(JoystickReport);
            break;
    }

    *DescriptorAddress = Address;


unclear changes.
do I need this in the make file? -DUSE_RAM_DESCRIPTORS



" qualifiers on all the descriptors" As in all that follow DeviceDescriptor, or does the ConfigurationDescriptor and HIDReport need to follow.



can I still define DeviceDescriptor like I was using

 USB_Descriptor_Device_t  DeviceDescriptor =
{
    .Header                 = {.Size = sizeof(USB_Descriptor_Device_t), .Type = DTYPE_Device},
.................
    .NumberOfConfigurations = FIXED_NUM_CONFIGURATIONS
};

and then just redefine the parts I need?


Thx for the help. Hope to get this working soon.

ulao

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Aug 23, 2021, 1:39:40 PMAug 23
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"if you want to retain some of them in Flash, you can undefine all the `USE_*_DESCRIPTORS` options and instead indicate the memory space in the `CALLBACK_USB_GetDescriptor` descriptor callback via the additional output parameter that will be enabled. "

If you are saying that I need to use all descriptors the same way, like the strings also... then yeah, that going to make a mess. So if I undefined all the USE_*_DESCRIPTORS
//        #define USE_RAM_DESCRIPTORS
//        #define USE_FLASH_DESCRIPTORS
//        #define USE_EEPROM_DESCRIPTORS
then how would one example look in the CALLBACK_USB_GetDescriptor ?

Address =  (*void) &DeviceDescriptor;
?

ulao

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Aug 23, 2021, 3:02:31 PMAug 23
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Ok, I see the call sign is changed now that I look at the code So I need to add the memory space

uint16_t CALLBACK_USB_GetDescriptor(const uint16_t wValue,
                                    const uint8_t wIndex,
                                    const void** const DescriptorAddress, uint8_t* const DescriptorMemorySpace)

and how to I access the DeviceDescriptor?
DescriptorMemorySpace.someArrayName[10]= 0x0d09;

?

ulao

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Aug 23, 2021, 3:39:43 PMAug 23
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I see what you are talking about namespace-wise now.

1) remove all defines for USE_*_DESCRIPTORS
2) change memory allocation to USB_Descriptor_Device_t  DeviceDescriptor
3) write a new call sign in h and c const void** const DescriptorAddress, uint8_t* const DescriptorMemorySpace)
4) default to     *DescriptorMemorySpace = MEMSPACE_FLASH;
but where needed use *DescriptorMemorySpace = MEMSPACE_RAM;
5) update what I need i.e DeviceDescriptor.ProductID = 0x0d09;

works :)
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