Explain why MickroC pic18f4550 HID example works

Posted by Dr Deo on Stack Overflow See other posts from Stack Overflow or by Dr Deo
Published on 2012-11-05T10:45:28Z Indexed on 2012/11/05 11:01 UTC
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usb

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microcontroller

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pic

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hid

MickroC compiler has a library for HID(Human Interface Device) usb communication. In the supplied samples, they specify that the buffers below should be in USB ram and use a pic18f4550.

unsigned char readbuff[64] absolute 0x500;   // Buffers should be in USB RAM, please consult datasheet
unsigned char writebuff[64] absolute 0x540;

But the pic18f4550 datasheet says USB ram ranges from 400h to 4FFh So why does their example work when their buffers appear not to be between 400h to 4FFh?
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