*ROM 7: Burnin' Rubber ROM 3
AlsoBy default, physical ROM 1 just like on Amstrad CPC, if there are no peripherals issuing ROMDIS=HIGH, then BASIC is mapped to all logical ROM 0banks (in range of 00h..7Fh). And on 6128+ only, physical ROM 3 is mapped to logical ROM 7. The ASIC is configured not to map it on 464+ and GX4000, even if a 6128+ cartridge is inserted.
Logical ROMs can be replaced by using a [[ROM board]] while physical ROMs cannot be replaced.