COP 4600 Project 2

1. COP 4600 Project 2

2. Task • Simulate booting the OS by loading the boot program into Kernel memory (which should be simulated as well) • Read instruction file boot.dat, save in memory • Interpret and run boot.dat University of Central Florida

3. Boot.dat • Three parts • Program attribute • Segment attribute • Instructions Program 1 Segment 1 Segment 2 Program 2 Segment 1 Segment 2 Segment 3 Segment 4 Memory Layout University of Central Florida

4. Boot.dat Program has 4 segments segment table. Load into MEMMAP Segment length Segment access bit one segment Input file boot.dat University of Central Florida

5. Program Skeleton In simulator.c Main() { …… Boot(); // Load boot.dat into memory, print out memory layout …… while( new_events != NULL ) { …… Interrupt(); // take out one event, print it out (consume one event) …… XPGM( ….); // Simulate a cpu cycle (generate one event) …… } } University of Central Florida

6. Memory Structure • Array “Mem” is your memory From simulator.c struct instr_type* Mem Mem = calloc(Mem_Size, sizeof(struct instr_type)); • Array “Mem_Map” is your segment table From simulator.c struct segment_type* Mem_Map Mem_Map = calloc(2*Max_Segments, sizeof(struct segment_type)); University of Central Florida

7. Memory Structure 0 SIO 75 1 DISK 2000 SKIP 0 2 3 JUMP [2,0] 4 SKIP 1 0 Boot.Seg1 JUMP [3,0] 5 6 SKIP 0 1 Boot.Seg2 JUMP [2,6] 7 2 Boot.Seg3 8 SIO 400 3 Boot.Seg4 PRNT 150 9 10 WIO 500 MEMMAP REQ [0,1] 11 12 WIO 0 REQ [2,1] 13 14 SKIP 0 JUMP [1,0] 15 END 20 16 MEM University of Central Florida

8. Instruction Set • SIO n • CPU burst for n cycles • Start IO • WIO n • CPU burst for n cycles • Wait IO (block) • END n • CPU burst for n cycles • End program University of Central Florida

9. Instruction Set • Device n • Always follows SIO • n is the bytes transferred (used to calculate time needed) • Device can be DISK, PRNT…… • Sample: SIO 75 DISK 2000 • REQ [seg, off] • Always follows WIO • [seg, off] refers to the device instruction waiting for • Sample: [2, 1] PRNT 150 …… WIO 0 REQ [2,1] University of Central Florida

10. Instruction Set • JUMP [seg, off] • Jump to [seg, off] • SKIP n • Skip the next instruction for n times • Sample SKIP 1 JUMP [3,0] SIO 400 University of Central Florida

11. Functions • Boot • Get_Instr // Read one instruction from boot.dat • Display_pgm // display memory layout • XPGM • CPU // One CPU cycle • Fetch // Read one instruction from memory • Util • Read • Write // Write one instruction to memory • Mu // convert [seg, off] to physical memory University of Central Florida

12. CPU • Every invocation of CPU() will execute one CPU burst instruction • SIO/WIO/END • SKIP • Skip or continue to next instruction • Jump • Jump to destination and continue • SIO • Skip the next instruction (device) • WIO • Skip the next instruction (req) University of Central Florida

13. Events • For every CPU invocation • Run one CPU burst, SIO/WIO/END • Generate one event of type “SIO/WIO/END” • Timestamp: the finish time of CPU burst [0,0] SIO 75 DISK 2000 SIO, 150ms [0,2] SKIP 0 JUMP [2,0] SIO 400 PRNT 150 SIO, 950ms 950ms = 150ms + 400(cpu burst)*2000ns = 950ms [2,0] Events CPU() invocations University of Central Florida

14. Develop process • Make copyfiles • Make data2files • Modify obj2.c • Reuse obj1.c, you may need to modify obj1.c • Make sim, then run “sim” • Make compare OBJ=2 • If error happens, manually check data2.out and ossim.out, see what is wrong • You should expect “Done. Looks OK to me...” • Make submit • You should see “If you dont get any error message,submit is successful.” University of Central Florida