CREDIT DOWN
BIOS routine called to deduct credits.
Input: $10FDB0 (BIOS_CREDIT_DEC) for player 1, and $10FDB1 (BIOS_CREDIT_DEC2) for player 2.
BIOS routine called to deduct credits.
Input: $10FDB0 (BIOS_CREDIT_DEC) for player 1, and $10FDB1 (BIOS_CREDIT_DEC2) for player 2.