Difference between revisions of "Lexicon"
From MSX Game Library
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== M == | == M == | ||
| − | * '''Memory space''': The total memory address space visible by the Z80 (64 KB from | + | * '''Mapper''': A device that contains one or more registers that allow to select the memory accessible through the pages where the device is selected. These registers are generally accessible either via I/O ports, or via write access to given addresses. |
| + | * '''Mapped-RAM''': A device with a mapper that allow to select chunk of the RAM (called 'segment') to be visible in each mapper's address blocs (called 'bank'). | ||
| + | * '''Mapped-ROM''': A device with a mapper that allow to select chunk of the ROM (called 'segment') to be visible in each mapper's address blocs (called 'bank'). | ||
| + | * '''MegaROM''': A ROM of 128 KB or more (1048576 bits, or 1 mega-bit, hence the name MegaROM). All MegaROM are Mapped-ROM. | ||
| + | * '''Memory space''': The total memory address space visible by the Z80 (64 KB from 0x0000 to 0xFFFF). | ||
== P == | == P == | ||
Latest revision as of 23:13, 13 February 2024
B
- Bank (mapper): A chunk of memory (8 or 16 KB) managed by a register that allow to select what part of the mapped ROM (segment) is visible in the given bank. For 8 KB mappers, there is 2 banks per page and for 16 KB one, there is 1 bank per page1.
M
- Mapper: A device that contains one or more registers that allow to select the memory accessible through the pages where the device is selected. These registers are generally accessible either via I/O ports, or via write access to given addresses.
- Mapped-RAM: A device with a mapper that allow to select chunk of the RAM (called 'segment') to be visible in each mapper's address blocs (called 'bank').
- Mapped-ROM: A device with a mapper that allow to select chunk of the ROM (called 'segment') to be visible in each mapper's address blocs (called 'bank').
- MegaROM: A ROM of 128 KB or more (1048576 bits, or 1 mega-bit, hence the name MegaROM). All MegaROM are Mapped-ROM.
- Memory space: The total memory address space visible by the Z80 (64 KB from 0x0000 to 0xFFFF).
P
- Page (memory): A quarter of the memory space (16 KB). The page number is defined by the 2 higher bits of the address. MSX allow to select an given slot/subslot to be visible in each page.
S
- Segment (mapper): A chunk of mapped ROM (8 or 16 KB) that can be selected into a given bank.