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lpc1769 usbhid example

Hi all,

I am trying the keil usbhid example with my board and gui. My aim is to send three adc value to my gui by usb. but i can send only one adc data, i can't send the other two. I have tried to change the descriptor file but i couldn't. I think i have to send my adc data as byte pockets, in other words as char array, but i couldn't set them. If you know how i can do it please help me.

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  • I'm really not good with USB, but one thing makes me curious.

    When something has a name wMaxPacketSize, that seems to indicate that the packet can actually be smaller. So if the packet can be max 8 bytes - how do the USB stack know if you want to send 8 bytes, or only 3 or 5? When data is processed in the other direction, there is a struct with a member SetupPacket.wLength that informs about about the amount of data.

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  • I'm really not good with USB, but one thing makes me curious.

    When something has a name wMaxPacketSize, that seems to indicate that the packet can actually be smaller. So if the packet can be max 8 bytes - how do the USB stack know if you want to send 8 bytes, or only 3 or 5? When data is processed in the other direction, there is a struct with a member SetupPacket.wLength that informs about about the amount of data.

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