megadrive_test1
annotate src/romhdr.S @ 4:e7138066c7ea
started the vdp.h header, and hastily rewrote the VDP test as C code
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Wed, 01 Feb 2017 13:40:50 +0200 |
| parents | |
| children |
| rev | line source |
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| nuclear@0 | 1 | the following will go into the custom .romhdr section which will be placed at |
| nuclear@0 | 2 | address 100 of the binary by the linker (see lnkscript). |
| nuclear@0 | 3 .section .romhdr,"a" |
| nuclear@0 | 4 |
| nuclear@0 | 5 #ifndef GAMENAME |
| nuclear@0 | 6 #define GAMENAME "unnamed" |
| nuclear@0 | 7 #endif |
| nuclear@0 | 8 #ifndef VERSTR |
| nuclear@0 | 9 #define VERSTR "00" |
| nuclear@0 | 10 #endif |
| nuclear@0 | 11 |
| nuclear@0 | 12 .ascii "SEGA MEGA DRIVE (C)MINDLAPSE2017" |
| nuclear@0 | 13 hdr_game_dom: |
| nuclear@0 | 14 .ascii GAMENAME |
| nuclear@0 | 15 hdr_game_dom_end: |
| nuclear@0 | 16 .fill 48 - (hdr_game_dom_end - hdr_game_dom),1,32 | pad to 48 bytes with spaces |
| nuclear@0 | 17 hdr_game_int: |
| nuclear@0 | 18 .ascii GAMENAME |
| nuclear@0 | 19 hdr_game_int_end: |
| nuclear@0 | 20 .fill 48 - (hdr_game_int_end - hdr_game_int),1,32 | pad to 48 bytes with spaces |
| nuclear@0 | 21 .ascii "GM" | it's a game (who cares what it is?) |
| nuclear@0 | 22 .ascii "0000000-" | product code |
| nuclear@0 | 23 .ascii VERSTR | version string |
| nuclear@0 | 24 .short 0 | checksum |
| nuclear@0 | 25 .ascii "J " | I/O support (joypad) |
| nuclear@0 | 26 .long 0 | start address of ROM |
| nuclear@0 | 27 .long _rom_end | last address of ROM |
| nuclear@0 | 28 .long 0xff0000 | start address of RAM |
| nuclear@0 | 29 .long 0xffffff | last address of RAM |
| nuclear@0 | 30 .long 0 | SRAM enabled(?) |
| nuclear@0 | 31 .long 0 | ??? |
| nuclear@0 | 32 .long 0 | start address of SRAM |
| nuclear@0 | 33 .long 0 | last address of SRAM |
| nuclear@0 | 34 .long 0 | ??? |
| nuclear@0 | 35 .long 0 | ??? |
| nuclear@0 | 36 .fill 40,1,32 | notes (fill with spaces for now TODO) |
| nuclear@0 | 37 .ascii "JUE " | country codes |