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My hello world rom (Genesis) runs on emulator, but in everdrive doesn't.

Humberto Moura - Feb 19, 2017

		Humberto Moura		Feb 19, 2017
			Hello guys, I made a hello world code based in Big evil corporation tutorial (https://bigevilcorporation.co.uk/2012/03/23/sega-m...), a great start tutorial. I think I understood the code, I made several changes, it runs well in emulators like Gens and others. But when I try to run the code in the Mega Drive (Genesis) Hardware Throught "Everdrive" cartridge, it doesn't run. The screen stays black after the "licenced by Sega tm" words. I compile my code in two forms: asm68k /k /p /o ae- main.asm, final.bin >errors.txt, , hello.lst asm68k /p main.asm,final.bin The code compiles without error, but no runs on Megadrive 1 JP with everdrive. I tried with SNASM68k too. Same thing. Compiles well, ran on emulator, but everdrive doesn't. After compile, I also used this two utilities to generate checksum: gen-cksum.py final.bin fixheadr.exe final.bin I don't know what's going wrong, because I compile the Sonic 1 project hack at the same form and runs on mega drive with everdrive well. I post all the source attached. Thanks for any help, . ---------------------------------------------------------------------------------------------------- ;main.asm include 'init.asm' include 'globals.asm' __main: move.w #0x8F02, vdp_control ; Configura o auto-incremento para 2 bytes move.l #vdp_write_palettes, vdp_control ; configura a VDP para escrever na CRAM 0x0000C3 lea Paletas, a0 ; Carrega endereço da paleta para o registrador a0 move.l #0x07, d0 ; 32 bytes de dados (8 longwords, menos 1 para o contador) na paleta (2 pal = 0F) .CorLoop: move.l (a0)+, vdp_data ; Move os dados para a porta de dados da VDP, e incrementa o endereço de origem dbra d0, .CorLoop move.w #0x8706, vdp_control ; Configura a cor de fundo para paleta 0 cor 6 - amarelo move.l #0x40200000, vdp_control ; Configura a VDP pra escrever no endereço da VRAM 0x0020 lea Caracteres, a0 ; Carrega endereço dos caracteres no a0 move.l #0x87, d0 ; (8 longwords * 8 letras = 64 longwords, menos 1 para contador) na fonte @Loop: move.l (a0)+, vdp_data ; Move dados para porta de dados da VDP, e incrementa endereço de origem dbra d0, @Loop move.l #vdp_write_plane_a, vdp_control ; Configura a VDP para escrever no endereço VRAM 0xC00000 (Plano A) ;plano A, paleta 0, sem girar, mais id do bloco (tile). move.w #0x0008, vdp_data ; Pattern ID 09 - H move.w #0x000F, vdp_data ; Pattern ID 07 - U move.w #0x000B, vdp_data ; Pattern ID 0C - M move.w #0x0002, vdp_data ; Pattern ID 0D - B move.w #0x0005, vdp_data ; Pattern ID 00 - E move.w #0x000D, vdp_data ; Pattern ID 17 - R move.w #0x000E, vdp_data ; Pattern ID 01 - T move.w #0x000C, vdp_data ; Pattern ID 10 - O move.w #0x0000, vdp_data ; Pattern ID 00 - move.w #0x000B, vdp_data ; Pattern ID 04 - M move.w #0x000C, vdp_data ; Pattern ID 12 - O move.w #0x000F, vdp_data ; Pattern ID 15 - U move.w #0x000D, vdp_data ; Pattern ID 07 - R move.w #0x0001, vdp_data ; Pattern ID 10 - A include 'cores.asm' include 'letras.asm' __end ; Última linha. Fim do endereço da ROM.