Editing FNX6809 Manuals

== MMU Registers ==
{| class="wikitable" style="text-align:center;"
|+
!Address
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|$FFA0
|RW
|MMU_MEM_CTRL
| - 
| - 
| colspan="2" |EDIT_LUT
| - 
| - 
| colspan="2" |ACT_LUT
|-
|$FFA1
|RW
|MMU_IO_CTRL
| - 
| - 
| - 
| - 
| - 
|
|$FFF0-$FFFF
Enable
|$FD00-$FDFF
Enable
|}

There are 4 MLUTs (MMU Lookup Tables). 

'''ACT_LUT''' these two bits specify which MLUT (0–3) is used to translate CPU bus address to system bus addresses.

'''EDIT_LUT''' these two bits will specify which MLUT (0 - 3) is being edited and will appear in memory addresses $FFA8-$FFAF.

These locations are defined in nitros9/defs/f256.d:

MMU_MEM_CTRL    equ       $FFA0

MMU_IO_CTRL        equ       $FFA1

MMU_SLOT_0          equ       $FFA8               $0000-$1FFF

MMU_SLOT_1          equ       $FFA9               $2000-$3FFF

MMU_SLOT_2          equ       $FFAA               $4000-$5FFF

MMU_SLOT_3          equ       $FFAB               $6000-$7FFF

MMU_SLOT_4          equ       $FFAC               $8000-$9FFF

MMU_SLOT_5          equ       $FFAD               $A000-$BFFF

MMU_SLOT_6          equ       $FFAE               $C000-$DFFF

MMU_SLOT_7          equ       $FFAF               $E000-$FFFF


<nowiki>*</nowiki> MMU_IO_CTRL bits

<nowiki>*</nowiki> $FFA1 has 2 bits:

<nowiki>*</nowiki>    FFA1[0] =

<nowiki>*</nowiki>        1 = Enable internal RAM for segment $FD00-$FDFF.

<nowiki>*</nowiki>        0 = Disable; RAM/FLASH is accessible.

<nowiki>*</nowiki>

<nowiki>*</nowiki>    FFA1[1] =

<nowiki>*</nowiki>        1 = Enable internal RAM for segment $FFF0-$FFFF

<nowiki>*</nowiki>        0 = Disable; RAM/FLASH is accessible.

<nowiki>*</nowiki> When enabled, the areas supersede RAM/flash, but will be disabled by RESET. When the system resets,

<nowiki>*</nowiki> those regions revert to RAM/flash. Also at RESET, the contents of RAM retain the old values until the

<nowiki>*</nowiki> system powers off.

'''NOTE:'''  If you are writing an OS-9 program, use <code>F$MapBlk</code> and <code>F$ClrBlk</code> instead of directly accessing these addresses. NitrOS-9 keeps track of each process' MMU LUT (but only if you use <code>F$MapBlk</code> and <code>F$ClrBlk</code>). Addressing the MMU directly can create unpredictable results.

== Memory Map ==
{|class="wikitable" style="text-align:center;"
|+
!MMU Block
!MMU Page + Sector
!CPU Space
!Absolute [A20:A0]
!WHAT
!MMU Page
|-
|2'b00
|6'b000_000-6'b000_111
|$0000-$1CFF
|$00_0000-$00_FCFF
|RAM
|MMU Page $00 to $07
|-
|2'b00
|6'b000_111
|$1D00-$1DFF
|$00_FD00-$00_FDFF
|256Byte Internal RAM (For OS9 Lvl 2)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E00-$1E1F
|$00_FE00-$00_FE1F
|I/O - System Control [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E20-$1E2F
|$00_FE20-$00_FE2F
|I/O - IRQ Controller [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E30-$1E3F
|$00_FE30-$00_FE3F
|I/O - TIMER [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E40-$1E4F
|$00_FE40-$00_FE4F
|I/O - RTC [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E50-$1E5F
|$00_FE50-$00_FE5F
|I/O - PS2 [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E60-$1E6F
|$00_FE60-$00_FE6F
|I/O - UART [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E70-$1E7F
|$00_FE70-$00_FE7F
|I/O - CODEC [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E80-$1E8F
|$00_FE80-$00_FE8F
|I/O - IEC [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1E90-$1E9F
|$00_FE90-$00_FE9F
|I/O - SDCARD [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1EA0-$1EAF
|$00_FEA0-$00_FEAF
|I/O - MOUSE Ctrl [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1EB0-$1EBF
|$00_FEB0-$00_FEBF
|I/O - VIA0 [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1EC0-$1EDF
|$00_FEC0-$00_FEDF
|I/O - DMA [32 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1EE0-$1EFF
|$00_FEE0-$00_FEFF
|I/O - MATH [32 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1F00-$1F3F
|$00_FF00-$00_FF3F
|TEXT LUT Foreground [64 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1F40-$1F7F
|$00_FF40-$00_FF7F
|TEXT LUT Background [64 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1F80-$1F8F
|$00_FF80-$00_FF8F
|I/O - SNES/NES Control [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1F90-$1F9F
|$00_FF90-$00_FF9F
|I/O - DIP SW [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FA0-$1FAF
|$00_FFA0-$00_FFAF
|MMU Control Registers [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FB0-$1FBF
|$00_FFB0-$00_FFBF
|I/O - VIA1 [16 Bytes] (F256K)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FC0-$1FDF
|$00_FFC0-$00_FFDF
|GRAPH - TinyVICKY Ctrl Reg [16 Bytes]
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FE0-$1FEF
|$00_FFE0-$00_FFEF
|RESERVED
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FF0-$1FF1
|$00_FFF0-$00_FFF1
|Reserved
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FF2-$1FF3
|$00_FFF2-$00_FFF3
|Vector - Software Interrupt 3 (SWI3)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FF4-$1FF5
|$00_FFF4-$00_FFF5
|Vector - Software Interrupt 2 (SWI2)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FF6-$1FF7
|$00_FFF6-$00_FFF7
|Vector - Fast Interrupt Request (FIRQ)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FF8-$1FF9
|$00_FFF8-$00_FFF9
|Vector - Interrupt Request (IRQ)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FFA-$1FFB
|$00_FFFA-$00_FFFB
|Vector - Software Interrupt 1 (SWI1)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FFC-$1FFD
|$00_FFFC-$00_FFFD
|Vector - Non-Maskable Interrupt (NMI)
|Permanent MMU Page $07
|-
|2'b00
|6'b000_111
|$1FFE-$1FFF
|$00_FFFE-$00_FFFF
|Vector - Reset (RESET)
|Permanent MMU Page $07
|-
|2'b00
|6'b001_000-6'b111_111
|$0000-$1FFF
|$01_0000-$07_FFFF
|RAM (448K) (Shared With Vicky)
|MMU Page $08 to $3F
|-
|2'b01
|6'b000_000-6'b111_111
|$0000-$1FFF
|$08_0000-$0F_FFFF
|FLASH (512K)
|MMU Page $40 to $7F
|-
|2'b10
|6'b000_000-6'b011_111
|$0000-$1FFF
|$10_0000-$13_FFFF
|CARTRIDGE(256K) RAM/FLASH
|MMU Page $80 to $9F
|-
|2'b10
|6'b100_000-6'b111_111
|$0000-$1FFF
|$14_0000-$17_FFFF
|RESERVED
|MMU Page $A0 to $BF
|-
|2'b11
|6'b000_000
|$0000-$03FF
|$18_0000-$18_03FF
|GRAPH - GAMMA B
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$0400-$07FF
|$18_0400-$18_07FF
|GRAPH - GAMMA G
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$0800-$0BFF
|$18_0800-$18_0BFF
|GRAPH - GAMMA R
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$0C00-$0FFF
|$18_0C00-$18_0FFF
|GRAPH - MOUSE Graphics
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$1000-$10FF
|$18_1000-$18_10FF
|GRAPH - BITMAP Registers
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$1100-$11FF
|$18_1100-$18_11FF
|GRAPH - TILE Registers
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$1200-$12FF
|$18_1200-$18_12FF
|GRAPH - MISC Registers
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$1300-$13FF
|$18_1300-$18_13FF
|GRAPH - SPRITE BANK 0
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$1400-$14FF
|$18_1400-$18_14FF
|GRAPH - SPRITE BANK 1
|MMU Page $C0
|-
|2'b11
|6'b000_000
|$1500-$1FFF
|$18_1500-$18_1FFF
|RESERVED
|MMU Page $C0
|-
|2'b11
|6'b000_001
|$0000-$07FF
|$18_2000-$18_27FF
|GRAPH - FONT MEMORY
|MMU Page $C1
|-
|2'b11
|6'b000_001
|$0800-$0BFF
|$18_2800-$18_2BFF
|GRAPH - LUT2
|MMU Page $C1
|-
|2'b11
|6'b000_001
|$0C00-$0FFF
|$18_2C00-$18_2FFF
|GRAPH - LUT3
|MMU Page $C1
|-
|2'b11
|6'b000_001
|$1000-$13FF
|$18_3000-$18_33FF
|GRAPH - LUT0
|MMU Page $C1
|-
|2'b11
|6'b000_001
|$1400-$17FF
|$18_3400-$18_37FF
|GRAPH - LUT1
|MMU Page $C1
|-
|2'b11
|6'b000_001
|$1800-$1FFF
|$18_3800-$18_3FFF
|RESERVED
|MMU Page $C1
|-
|2'b11
|6'b000_010
|$0000-$12BF
|$18_4000-$18_52BF
|GRAPH - TEXT MEMORY (80x60 Max)
|MMU Page $C2
|-
|2'b11
|6'b000_010
|$12C0-$1FFF
|$18_52C0-$18_5FFF
|RESERVED
|MMU Page $C2
|-
|2'b11
|6'b000_011
|$0000-$12BF
|$18_6000-$18_72BF
|GRAPH - COLOR MEMORY (80x60 Max)
|MMU Page $C3
|-
|2'b11
|6'b000_011
|$12C0-$1FFF
|$18_72C0-$18_7FFF
|RESERVED
|MMU Page $C3
|-
|2'b11
|6'b000_100
|$0000-$001F
|$18_8000-$18_801F
|SOUND - SID LEFT
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0080-$009F
|$18_8080-$18_809F
|SOUND - SID MONO
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0100-$011F
|$18_8100-$18_811F
|SOUND - SID RIGHT
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0180
|$18_8180
|SOUND - OPL3 ADDY REG Low (F256K)
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0181
|$18_8181
|SOUND - OPL3 DATA REG (F256K)
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0182
|$18_8182
|SOUND - OPL3 ADDY REG Hi (F256K)
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0200-$0207
|$18_8200-$18_8207
|SOUND - PSG LEFT
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0208-$020F
|$18_8208-$18_820F
|SOUND - PSG MONO
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0210-$0217
|$18_8210-$18_8217
|SOUND - PSG RIGHT
|MMU Page $C4
|-
|2'b11
|6'b000_100
|$0218-$1FFF
|$18_8218-$18_9FFF
|RESERVED
|MMU Page $C4
|-
|2'b11
|6'b000_101-6'b111_111
|$0000-$1FFF
|$18_A000-$1F_FFFF
|NOTHINGNESS - RESERVED
|MMU Page $C5-$FF
|}

== Memory Model ==
[[File:FNX6809-MemoryModel Page 1.png|thumb|430x430px|FNX6809 Memory Model Page 1|none]]
[[File:FNX6809-MemoryModel Page 2.png|none|thumb|430x430px|FNX6809 Memory Model Page 2]]
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