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r8780 Sunday 15th August, 2010 at 07:38:41 UTC by Robbbert
[GAMECOM] Unknown opcode 5B added so that the remaining carts (quizwiz, weblink indy500, etc) will boot.
[src/emu/cpu/sm8500]sm85ops.h

src/emu/cpu/sm8500/sm85ops.h
r8779r8780
12761276   break;
12771277case 0x5B:   /* unk5B - 6,7,11,8,7 cycles */
12781278logerror( "%04X: unk%02x\n", cpustate->PC-1,op );
1279   ARG_ad16;
1279/* NOTE: This unknown command is used in several carts, the code below allows those carts to boot */
1280   ARG_iR;
1281   r1 = r2 & 7;
1282   res = sm85cpu_mem_readbyte( cpustate, r1 ) + 1;
1283   sm85cpu_mem_writebyte( cpustate, r1, res );
12801284   mycycles += 6;
12811285   break;
12821286case 0x5C:   /* DIV RRr,RRs - 47 cycles - Flags affected: -Z-V---- */

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