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→Updating keydata
The contents of the keyslot specified in REG_AESKEYCNT can be updated by consecutively writing four words to REG_AESKEYXFIFO (keyX), REG_AESKEYYFIFO(keyY), or REG_AESKEYFIFO (normalkey).
The contents of the keyslot specified in REG_AESKEYCNT can be updated by consecutively writing four words to REG_AESKEYXFIFO (keyX), REG_AESKEYYFIFO(keyY), or REG_AESKEYFIFO (normalkey).
After writing to a keyslot, the keyslot in REG_AESKEYCNT must be set again, even when writing to the same keyslot.
After writing to a keyslot, the keyslot must be selected again(write REG_AESKEYSEL + set REG_AESCNT bit26), even when writing to the same keyslot.
Writing to the key FIFOs with byte writes results in the AES engine converting the byte to a word for setting the key word, with this: word = (byteval) | (byteval<<8) | (byteval<<16) | (byteval<<24). The result is the same regardless of which FIFO register byte was written to.
Writing to the key FIFOs with byte writes results in the AES engine converting the byte to a word for setting the key word, with this: word = (byteval) | (byteval<<8) | (byteval<<16) | (byteval<<24). The result is the same regardless of which FIFO register byte was written to.