11.5 Disk Types (ROM Area and RAM Area)


A feature of the 64DD is that it can not only read but also write. However, it cannot write to all areas. The non-writable area is called the ROM area, and the writable area is called the RAM area. The relative proportion of the ranges of these two areas varies with each of the seven disk types available.

Relation Between Disk Type and ROM Area, RAM Area

Disk Type ROM Area RAM Area
Type 0 zones 0-2(26,014,080 bytes) zones 3-8(38,444,480 bytes)
Type 1 zones 0-3(34,957,440 bytes) zones 4-8(29,501,120 bytes)
Type 2 zones 0-4(43,155,520 bytes) zones 5-8(21,303,040 bytes)
Type 3 zones 0-5(50,608,320 bytes) zones 6-8(13,850,240 bytes)
Type 4 zones 0-6(57,315,840 bytes) zones 7-8(7,142,720 bytes)
Type 5 zones 0-7(62,516,480 bytes) zones 8(1,942,080 bytes)
Type 6 entire area(64,458,560 bytes) None

The developer decides the disk type for each disk according to the amount of write area the game requires.