M68K can push the reset button (actually, make VRES signal active) for prepare own hardware. There are "RESET" opcode (0x4E70), wich does things:
Description: Asserts the RSTO signal for 512 (124 for MC68000, MC68EC000, MC68HC000, MC68HC001, MC68008, MC68010, and MC68302) clock periods, resetting all external devices. The processor state, other than the program counter, is unaffected, and execution continues with the next instruction.
I think it usefull to use this opcode before jump to inital vector. So, do it this way:
ASM inline can be used, does it?
But, I don't know for sure, affects this opcode on MegaDrive hardware or not. But VRES is directly connected to RESET pin of M68K, so cartrige hardware can be reset this way.