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Memory Map

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Bob Frasure edited this page Jan 6, 2025 · 1 revision

The 2MB physical address space available to the HuC6280 contains all of the memory-mapped I/O necessary to interface with the other chips, the CD subsystem, and the user (through the HuCard and joystick ports). Below is the full memory map for the TurboGrafx / PC Engine family. Each segment is labeled with its corresponding MPR register value ($00 - $FF), a description of the segment's use, its physical address location, and a "chip enable signal" or other descriptive text. The Develo Book describes the chip enable signal as an external signal that becomes true when that area of memory is accessed. Currently, it is not known if these signals correspond with any pins or traces available on the system motherboard. Signals in parentheses, such as ([o]CEP[/o]), represent chip enable signals that are internal to the HuC6280. The notation [o]SIGNAME[/o] is equivalent to a negative logic signal; that is, the signal is active when it is low instead of high.

Page generated by Memory Map Generator.

Independent Memory Maps

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Standard hardware (PC-Engine, CoreGrafx, CoreGrafx II, TurboGrafx 16)

Physical Addresses Segment : Address Description Chip enable signal
1FF400 - 1FF7FF FF:1400 - FF:17FF Interrupt controller [o]CECG[/o] (internal)
1FF000 - 1FF3FF FF:1000 - FF:13FF 8-bit I/O port [o]CEIO[/o] (internal)
1FE800 - 1FEBFF FF:0800 - FF:0BFF PSG registers [o]CEP[/o] (internal)
1FE400 - 1FE7FF FF:0400 - FF:07FF VCE registers [o]CEK[/o]
1FE000 - 1FE3FF FF:0000 - FF:03FF VDC registers [o]CE7[/o] (HuC6280 pin 60)
1F0000 - 1F7FFF F8:0000 - FB:1FFF Work RAM (8K, mirrored four times) [o]CER[/o] (HuC6280 pin 61)
000000 - 0FFFFF 00:0000 - 7F:1FFF HuCard/TurboChip ROM ROM [o]CE[/o] (A20)

SuperGrafx additions

Physical Addresses Segment : Address Description Chip enable signal
1FE020 - 1FE3FF FF:0020 - FF:03FF Copy of 32-byte register block (mirrored repeatedly) [o]CE7[/o] (HuC6280 pin 60)
1FE018 - 1FE01F FF:0018 - FF:001F (Unused) [o]CE7[/o] (HuC6280 pin 60)
1FE010 - 1FE017 FF:0010 - FF:0017 VDC #2 registers [o]CE7[/o] (HuC6280 pin 60)
1FE008 - 1FE00F FF:0008 - FF:000F VPC registers [o]CE7[/o] (HuC6280 pin 60)
1FE000 - 1FE007 FF:0000 - FF:0007 VDC #1 registers [o]CE7[/o] (HuC6280 pin 60)
1F0000 - 1F7FFF F8:0000 - FB:1FFF Work RAM (32K) [o]CER[/o] (HuC6280 pin 61)

IFU-30 additions

Physical Addresses Segment : Address Description Chip enable signal
1FE800 - 1FF80F FF:0800 - FF:180F CD-ROM / ASIC registers [o]CEP[/o] (internal)
1EE000 - 1EE7FF F7:0000 - F7:07FF Back-up RAM (2K) [o]CER[/o] (HuC6280 pin 61)
100000 - 10FFFF 80:0000 - 87:1FFF Work RAM (64K) [o]CER[/o] (HuC6280 pin 61)

TurboBooster+ additions

Physical Addresses Segment : Address Description Chip enable signal
1FE800 - 1FF80F FF:0800 - FF:180F ASIC registers (only relating to back-up RAM control) [o]CEP[/o] (internal)
1EE000 - 1EE7FF F7:0000 - F7:07FF Back-up RAM (2K) [o]CER[/o] (HuC6280 pin 61)

Super CD-ROM2 additions

Physical Addresses Segment : Address Description Chip enable signal
1FE800 - 1FFBFF FF:0800 - FF:1BFF CD-ROM / ASIC registers [o]CEP[/o] (internal)
1EE000 - 1EE7FF F7:0000 - F7:07FF Back-up RAM (2K) [o]CER[/o] (HuC6280 pin 61)
100000 - 10FFFF 80:0000 - 87:1FFF Work RAM (64K) [o]CER[/o] (HuC6280 pin 61)
0D0000 - 0FFFFF 68:0000 - 7F:1FFF Work RAM (192K) ROM [o]CE[/o] (A20)
000000 - 07FFFF 00:0000 - 3F:1FFF BIOS ROM (512K) ROM [o]CE[/o] (A20)

System Card (v1.x, v2.x) additions

Physical Addresses Segment : Address Description Chip enable signal
000000 - 03FFFF 00:0000 - 1F:1FFF BIOS ROM (256K) ROM [o]CE[/o] (A20)

System Card (v3.x) additions

Physical Addresses Segment : Address Description Chip enable signal
1FF800 - 1FF9FF FF:1800 - FF:19FF ID locations [o]CECG[/o] (internal)
0D0000 - 0FFFFF 68:0000 - 7F:1FFF Work RAM (192K) ROM [o]CE[/o] (A20)
000000 - 07FFFF 00:0000 - 3F:1FFF BIOS ROM (512K) ROM [o]CE[/o] (A20)

Arcade Card DUO additions

Physical Addresses Segment : Address Description Chip enable signal
1FFA00 - 1FFBFF FF:1A00 - FF:1BFF Arcade Card I/O ports [o]CECG[/o] (internal)
1FF800 - 1FF9FF FF:1800 - FF:19FF ID locations [o]CECG[/o] (internal)
080000 - 087FFF 40:0000 - 43:1FFF Arcade Card I/O pages ROM [o]CE[/o] (A20)

Arcade Card Pro additions

Physical Addresses Segment : Address Description Chip enable signal
1FFA00 - 1FFBFF FF:1A00 - FF:1BFF Arcade Card I/O ports [o]CECG[/o] (internal)
1FF800 - 1FF9FF FF:1800 - FF:19FF ID locations [o]CECG[/o] (internal)
0D0000 - 0FFFFF 68:0000 - 7F:1FFF Work RAM (192K) ROM [o]CE[/o] (A20)
080000 - 087FFF 40:0000 - 43:1FFF Arcade Card I/O pages ROM [o]CE[/o] (A20)
000000 - 07FFFF 00:0000 - 3F:1FFF BIOS ROM (512K) ROM [o]CE[/o] (A20)

HuCard/TurboChip "split" format

Physical Addresses Segment : Address Description Chip enable signal
080000 - 0FFFFF 40:0000 - 7F:1FFF Mask ROM #2 (can be 128K, 256K) ROM [o]CE[/o] (A20)
000000 - 07FFFF 00:0000 - 3F:1FFF Mask ROM #1 (can be 128K, 256K) ROM [o]CE[/o] (A20)

HuCard/TurboChip standard format

Physical Addresses Segment : Address Description Chip enable signal
000000 - 0FFFFF 00:0000 - 7F:1FFF Mask ROM (can be 128K, 256K, 512K) ROM [o]CE[/o] (A20)

Street Fighter II CE (HuCard)

Physical Addresses Segment : Address Description Chip enable signal
080000 - 0FFFFF 40:0000 - 7F:1FFF ROM bank (512K of 2MB) ROM [o]CE[/o] (A20)
000000 - 07FFFF 00:0000 - 3F:1FFF ROM (512K, fixed) ROM [o]CE[/o] (A20)
001FF0 - 001FF3 00:1FF0 - 00:1FF3 Bank select registers (write to 1FFx to map ROM bank #x to to the bank area) ROM [o]CE[/o] (A20)

"ROMRAM" HuCard (Populous, Tennokoe Bank)

Physical Addresses Segment : Address Description Chip enable signal
?????? - ?????? ??:???? - ??:???? Battery-backed RAM
000000 - 0FFFFF 00:0000 - 7F:1FFF Game ROM (256K) ROM [o]CE[/o] (A20)

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