Gorf Posted June 25, 2010 Share Posted June 25, 2010 To jump around in main RAM..... 1 ) Within a 256 byte page boundary...ie..The address range of a page starts at $XXXXXX00 and ends at $XXXXXXFF. a ) JR can jump from anywhere to anywhere within its range and inside the page. b ) JUMP must be aligned on a long address and jump to a word offset long address...ie...adresses ending in 2,6,A and E 2 ) From one 256 byte page to another a ) JR (if it can reach the destination) can jump from anywhere but MUST land on a long aligned address to the other page. b ) JUMP must be aligned on a long address and jump to a long aligned address...ie...adresses ending in 0,4,8 and C. 3 ) To jump from main to local or local to main(from one way to the other is the same). a ) The JUMP must be long aligned. The desination must be long aligned. However, phrase aligment is reccomended for saftey. b ) Preceed the JUMP with a MOVEI not related to the JUMP register(although I've had success with, Owl says its not safe.) c ) Obviously JR can not reach main RAM from the GPU local address so it will not work for this JR/JUMP must be followed by 2 NOP's OR 1 single register instruction not associated with anything recent and then NOP. I do not think the single instruction and 1 NOP will work between local to main or main to local but I'll leave that up to Owl to answer. 1 Quote Link to comment Share on other sites More sharing options...
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