Labels:bird | bulletin board | plant | reckoner | sky | trade name OCR: Memory 1FFFF ar 1FFFF 20000 82 80286 20001 20002 20003 The 80286 reads the pord value 8382h at address 20000h with single pord sized access since that word value starts an ever address Memory 1FFFF IFFFH To 80286 20000 2000 20002 20003 The 80286 reads the pord value 8281h at address 1FFFFh with twa byte- sized accesses, since that pord value starts at an ppo address FIGURI 15.1 The data alignment cycle eater A The 80286 needs just one word sized memory access to read or write of nenory that starts at an even address (a) However the 80286 must perform two byte sized memory accesses which together take twice as long as one sized access -when asked to read or write A word of 11en1ory that starts at an ppo address. Apart from execution time, the whole process is transparent to instructions tha ...
(.png)
