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'''Model names''': Certain features are only available on certain models, and these terms are used exactly. For instance, "F256Jr" means exactly the 1st gen Jr, not the entire Jr line.
'''Model names''': Certain features are only available on certain models, and these terms are used exactly. For instance, "F256Jr" means exactly the 1st gen Jr, not the entire Jr line.


<span id="BGRx>'''BGRx'''</span>: A 4-byte aligned color entry in Blue, Green, Red order, with the 4th byte unused.
<span id="BGR">'''BGR'''</span>: A 3-byte color entry in Blue, Green, Red order.
 
<span id="BGRx">'''BGRx'''</span>: A 4-byte aligned color entry in Blue, Green, Red order, with the 4th byte unused.


== IO Page 0 ==
== IO Page 0 ==
====== $C000 Gamma Lookup ======
{| class="wikitable"
{| class="wikitable"
|+Gamma Lookup
!MMU
!MMU
!Flat
!Flat
Line 35: Line 38:
|Red gamma conversion table
|Red gamma conversion table
|}
|}
====== $CC00: Mouse Pointer Bitmap ======
See: [[Use the PS/2 Mouse]]
{| class="wikitable"
{| class="wikitable"
|+Mouse Pointer
!MMU
!MMU
!Flat
!Flat
Line 50: Line 55:
|}
|}


=== Master Control Registers ($D0xx, $F0:10xx) ===
===== $D000: VICKY Config =====
 
====== $D000: Master Control Registers ======
{| class="wikitable"
{| class="wikitable"
|+Master Control
!MMU
!MMU
!Flat
!Flat
Line 115: Line 121:


'''FON_SET''': Chooses font set 0 or 1
'''FON_SET''': Chooses font set 0 or 1
====== $D002: Layers ======
{| class="wikitable"
{| class="wikitable"
|+Layer Configuration
!MMU
!MMU
!Flat
!Flat
Line 157: Line 164:
4-6: Tilemap 0-2
4-6: Tilemap 0-2
|}
|}
====== $D004: Border ======
{| class="wikitable"
{| class="wikitable"
|+Border
!MMU
!MMU
!Flat
!Flat
Line 219: Line 227:
| colspan="5" |SIZE_Y
| colspan="5" |SIZE_Y
|}
|}
====== $D00D: Background ======
{| class="wikitable"
{| class="wikitable"
|+Background Color
!MMU
!MMU
!Flat
!Flat
Line 252: Line 261:
| colspan="8" |Background color Red component
| colspan="8" |Background color Red component
|}
|}
====== $D010: Text Cursor ======
{| class="wikitable"
{| class="wikitable"
|+Text Cursor
!MMU
!MMU
!Flat
!Flat
Line 271: Line 281:
|RW
|RW
|CCR
|CCR
|
|
|
|
|
|
|
|
|FLASH_DIS
|FLASH_DIS
| colspan="2" |RATE
| colspan="2" |RATE
Line 306: Line 316:
| colspan="8" |Cursor Y position (16-bit)
| colspan="8" |Cursor Y position (16-bit)
|}
|}
====== $D018: Raster ======
{| class="wikitable"
{| class="wikitable"
|+Raster
!MMU
!MMU
!Flat
!Flat
Line 337: Line 348:
|W
|W
|LINT_CTRL
|LINT_CTRL
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|ENABLE
|ENABLE
|-
|-
Line 353: Line 364:
|}
|}


=== Bitmap Control Registers ($D1xx, $F0:11xx) ===
===== $D100: Bitmaps =====
{| class="wikitable"
{| class="wikitable"
|+Bitmaps
!MMU
!MMU
!Flat
!Flat
Line 371: Line 381:
|$D100
|$D100
|$F0:1100
|$F0:1100
|RW
|
|
|
|
|
| colspan="8" |Bitmap 0
|
|
|
| colspan="2" |CLUT
|ENABLE
|-
|$D101
|$F0:1101
|RW
|
| colspan="8" |[[IO Pages#SRAM Address|SRAM Address]] of bitmap 0 pixels (24-bit)
|-
|-
|$D108
|$D108
|$F0:1108
|$F0:1108
|RW
|
|
|
|
|
|
|
| colspan="2" |CLUT
|ENABLE
|-
|$D109
|$F0:1109
|RW
|
|
| colspan="8" |[[IO Pages#SRAM Address|SRAM Address]] of bitmap 1 pixels (24-bit)
| colspan="8" |Bitmap 1
|-
|-
|$D110
|$D110
|$F0:1110
|$F0:1110
|RW
|
|
|
|
|
|
| colspan="8" |Bitmap 2
|-
|
|
| +0
|RW
|
|
|—
|—
|—
|—
|—
| colspan="2" |CLUT
| colspan="2" |CLUT
|ENABLE
|ENABLE
|-
|-
|$D111
|
|$F0:1111
| +1
|RW
|RW
|
|
| colspan="8" |[[IO Pages#SRAM Address|SRAM Address]] of bitmap 2 pixels (24-bit)
| colspan="8" |[[IO Pages#SRAM Address|SRAM Address]] of pixels (24-bit)
|}
|}


=== Tilemap Control Registers ($D2xx, $F0:12xx) ===
===== $D200: Tilemaps =====
{| class="wikitable"
{| class="wikitable"
!MMU
!MMU
Line 461: Line 453:
|W
|W
|
|
|
|
|
|
|
|
|TILE_SIZE_8
|TILE_SIZE_8
|
|
|
|
|
|
|ENABLE
|ENABLE
|-
|-
Line 520: Line 512:
| colspan="4" |Y[7:4]
| colspan="4" |Y[7:4]
|}
|}
====== $D280: Tilesets ======
{| class="wikitable"
{| class="wikitable"
|+Tilesets
!MMU
!MMU
!Flat
!Flat
Line 602: Line 595:
|—
|—
|}
|}
===== $D400: Sound =====
====== $D400: SID chips ======
{| class="wikitable"
{| class="wikitable"
|+
!MMU
!MMU
!Flat
!Flat
Line 659: Line 655:
|
|
| colspan="4" |ATTACK
| colspan="4" |ATTACK
|DELAY
| colspan="4" |DELAY
|
|
|
|-
|-
|
|
Line 701: Line 694:
|
|
| colspan="4" |ATTACK
| colspan="4" |ATTACK
|DELAY
| colspan="4" |DELAY
|
|
|
|-
|-
|
|
Line 743: Line 733:
|
|
| colspan="4" |ATTACK
| colspan="4" |ATTACK
|DELAY
| colspan="4" |DELAY
|
|
|
|-
|-
|
|
Line 792: Line 779:
| colspan="4" |VOLUME
| colspan="4" |VOLUME
|}
|}
====== $D580: OPL3 (NOT on F256Jr!) ======
Main page: [[Use the OPL3 YMF262]]
{| class="wikitable"
{| class="wikitable"
|+OPL3 Registers (NOT ON F256JR)
!MMU
!MMU
!Flat
!Flat
Line 825: Line 814:
| colspan="8" |Address register for ports $100 - $1FF
| colspan="8" |Address register for ports $100 - $1FF
|}
|}
====== $D600: PSGs ======
Main page: [[Use the PSG]]
{| class="wikitable"
{| class="wikitable"
|+PSG Registers
!MMU
!MMU
!Flat
!Flat
Line 859: Line 850:
|}
|}
Note the stereo separation is controlled with the '''PSG_ST''' flag.
Note the stereo separation is controlled with the '''PSG_ST''' flag.
====== $D620: CODEC ======
Main page: [[Use the CODEC]]
{| class="wikitable"
{| class="wikitable"
|+CODEC Registers
!MMU
!MMU
!Flat
!Flat
Line 913: Line 906:
|START
|START
|}
|}
===== $D630: System =====
====== $D630: UART ======
{| class="wikitable"
{| class="wikitable"
|+UART Registers
!MMU
!MMU
!Flat
!Flat
Line 1,007: Line 1,003:
| colspan="2" |DATA
| colspan="2" |DATA
|}
|}
====== $D640: PS/2 ======
See: [[Use the PS/2 Mouse]]
{| class="wikitable"
{| class="wikitable"
|+PS/2 Registers
!MMU
!MMU
!Flat
!Flat
Line 1,066: Line 1,064:
|KEMP
|KEMP
|}
|}
====== $D650: Timers ======
{| class="wikitable"
{| class="wikitable"
|+Timer Registers
!MMU
!MMU
!Flat
!Flat
Line 1,196: Line 1,195:
| colspan="8" |CMP (24-bit)
| colspan="8" |CMP (24-bit)
|}
|}
====== $D660: Interrupts ======
Main page: [[IRQ]], [[IRQ Programming]]
{| class="wikitable"
{| class="wikitable"
|+Interrupt Registers
!MMU
!MMU
!Flat
!Flat
Line 1,212: Line 1,213:
|-
|-
|$D660
|$D660
|
|$F0:1660
|
|
|INT_PENDING
|INT_PENDING
Line 1,218: Line 1,219:
|-
|-
|$D664
|$D664
|
|$F0:1664
|
|
|INT_POLARITY
|INT_POLARITY
Line 1,224: Line 1,225:
|-
|-
|$D668
|$D668
|
|$F0:1668
|
|
|INT_EDGE
|INT_EDGE
Line 1,230: Line 1,231:
|-
|-
|$D66C
|$D66C
|
|$F0:166C
|
|
|INT_MASK
|INT_MASK
Line 1,236: Line 1,237:
|-
|-
|
|
| +0 & $01
|
|
|INT_VKY_SOF
| colspan="8" |Start of Frame interrupt (beginning of VSYNC)
|-
|
|
| +0 & $02
|
|
|INT_VKY_SOL
| colspan="8" |Start of Line interrupt
|-
|
|
| +0 & $04
|
|
|INT_PS2_KBD
| colspan="8" |PS/2 keyboard event
|-
|
|
| +0 & $08
|
|
|INT_PS2_MOUSE
| colspan="8" |PS/2 mouse event
|-
|
|
| +0 & $10
|
|
|INT_TIMER_0
| colspan="8" |TIMER0 has reached its target value
|-
|
|
| +0 & $20
|
|
|}
|INT_TIMER_1
{| class="wikitable"
| colspan="8" |TIMER1 has reached its target value
|+Interrupt flags
!Offset
!Mask
!Name
!Description
|-
|-
|0
|
|$01
| +0 & $80
|INT_VKY_SOF
|
|Start of Frame interrupt (beginning of VSYNC)
|INT_CARTRIDGE
| colspan="8" |Interrupt asserted from cartridge port
|-
|-
|0
|
|$02
|
|INT_VKY_SOL
|
|Start of Line interrupt
|
| colspan="8" |
|-
|-
|0
|
|$04
| +1 & $01
|INT_PS2_KBD
|
|PS/2 keyboard event
|INT_UART
|-
| colspan="8" |The UART is ready to receive or send data
|0
|$08
|INT_PS2_MOUSE
|PS/2 mouse event
|-
|0
|$10
|INT_TIMER_0
|TIMER0 has reached its target value
|-
|0
|$20
|INT_TIMER_1
|TIMER1 has reached its target value
|-
|0
|$80
|INT_CARTRIDGE
|Interrupt asserted from cartridge port
|-
|-
|
|
| +1 & $10
|
|
|INT_RTC
| colspan="8" |Interrupt from real time clock chip
|-
|
|
| +1 & $20
|
|
|-
|1
|$01
|INT_UART
|The UART is ready to receive or send data
|-
|1
|$10
|INT_RTC
|Interrupt from real time clock chip
|-
|1
|$20
|INT_VIA0
|INT_VIA0
|Event from the joystick VIA chip
| colspan="8" |Event from the joystick VIA chip
|-
|-
|1
|
|$40
| +1 & $40
|
|INT_VIA1
|INT_VIA1
|Event from the keyboard VIA chip (F256k Series Only!)
| colspan="8" |Event from the keyboard VIA chip (F256k Series Only!)
|-
|-
|1
|
|$80
| +1 & $80
|
|INT_SDC_INS
|INT_SDC_INS
|SD Card has been inserted
| colspan="8" |SD Card has been inserted
|-
|-
|
|
Line 1,324: Line 1,318:
|
|
|
|
| colspan="8" |
|-
|-
|2
|
|$01
| +2 & $01
|
|IEC_DATA_i
|IEC_DATA_i
|IEC data in
| colspan="8" |IEC data in
|-
|-
|2
|
|$02
| +2 & $02
|
|IEC_CLK_i
|IEC_CLK_i
|IEC clock in
| colspan="8" |IEC clock in
|-
|-
|2
|
|$04
| +2 & $04
|
|IEC_ATN_i
|IEC_ATN_i
|IEC attention in
| colspan="8" |IEC attention in
|-
|-
|2
|
|$08
| +2 & $08
|
|IEC_SREQ_i
|IEC_SREQ_i
|IEC service request in
| colspan="8" |IEC service request in
|}
|}
====== $D670: DIP Switches ======
Main page: [[DIP switches]]
{| class="wikitable"
{| class="wikitable"
|+DIP Switches
!MMU
!MMU
!Flat
!Flat
Line 1,361: Line 1,362:
|-
|-
|$D670
|$D670
|
|$F0:1670
|R
|R
|
|
Line 1,370: Line 1,371:
| colspan="4" |BOOT
| colspan="4" |BOOT
|}
|}
====== $D680: IEC ======
{| class="wikitable"
{| class="wikitable"
|+IEC Registers
!MMU
!MMU
!Flat
!Flat
Line 1,386: Line 1,388:
|-
|-
|$D680
|$D680
|
|$F0:1680
|R
|R
|IEC_I
|IEC_I
Line 1,399: Line 1,401:
|-
|-
|$D681
|$D681
|
|$F0:1681
|RW
|RW
|IEC_O
|IEC_O
Line 1,411: Line 1,413:
|DAT_o
|DAT_o
|}
|}
====== $D690: RTC ======
{| class="wikitable"
{| class="wikitable"
|+RTC Registers
!MMU
!MMU
!Flat
!Flat
Line 1,427: Line 1,430:
|-
|-
|$D690
|$D690
|
|$F0:1690
|RW
|RW
|Seconds
|Seconds
Line 1,435: Line 1,438:
|-
|-
|$D691
|$D691
|
|$F0:1691
|RW
|RW
|Seconds Alarm
|Seconds Alarm
Line 1,443: Line 1,446:
|-
|-
|$D692
|$D692
|
|$F0:1692
|RW
|RW
|Minutes
|Minutes
Line 1,451: Line 1,454:
|-
|-
|$D693
|$D693
|
|$F0:1693
|RW
|RW
|Minutes Alarm
|Minutes Alarm
Line 1,459: Line 1,462:
|-
|-
|$D694
|$D694
|
|$F0:1694
|RW
|RW
|Hours
|Hours
Line 1,468: Line 1,471:
|-
|-
|$D695
|$D695
|
|$F0:1695
|RW
|RW
|Hours Alarm
|Hours Alarm
Line 1,477: Line 1,480:
|-
|-
|$D696
|$D696
|
|$F0:1696
|RW
|RW
|Days
|Days
Line 1,486: Line 1,489:
|-
|-
|$D697
|$D697
|
|$F0:1697
|RW
|RW
|Days Alarm
|Days Alarm
Line 1,495: Line 1,498:
|-
|-
|$D698
|$D698
|
|$F0:1698
|RW
|RW
|Day of Week
|Day of Week
Line 1,506: Line 1,509:
|-
|-
|$D699
|$D699
|
|$F0:1699
|RW
|RW
|Month
|Month
Line 1,516: Line 1,519:
|-
|-
|$D69A
|$D69A
|
|$F0:169A
|RW
|RW
|Year
|Year
Line 1,523: Line 1,526:
|-
|-
|$D69B
|$D69B
|
|$F0:169B
|RW
|RW
|Rates
|Rates
Line 1,531: Line 1,534:
|-
|-
|$D69C
|$D69C
|
|$F0:169C
|RW
|RW
|Enables
|Enables
Line 1,544: Line 1,547:
|-
|-
|$D69D
|$D69D
|
|$F0:169D
|RW
|RW
|Flags
|Flags
Line 1,557: Line 1,560:
|-
|-
|$D69E
|$D69E
|
|$F0:169E
|RW
|RW
|Control
|Control
Line 1,570: Line 1,573:
|-
|-
|$D69F
|$D69F
|
|$F0:169F
|RW
|RW
|Century
|Century
Line 1,576: Line 1,579:
| colspan="4" |1s digit
| colspan="4" |1s digit
|}
|}
====== $D6A0: System Control Registers ======
Main page: [[Use the LEDs]]
{| class="wikitable"
{| class="wikitable"
|+System Control Registers
!MMU
!MMU
!Flat
!Flat
Line 1,592: Line 1,597:
|-
|-
|$D6A0
|$D6A0
|
|$F0:16A0
|W
|W
|SYS0
|SYS0
Line 1,607: Line 1,612:
|
|
|R
|R
|
|SYS0
|—
|—
|SD_WP
|SD_WP
Line 1,618: Line 1,623:
|-
|-
|$D6A1
|$D6A1
|
|$F0:16A1
|RW
|RW
|SYS1
|SYS1
Line 1,628: Line 1,633:
|L0_MN
|L0_MN
|}
|}
====== $D6A7: F256k Series LEDs ======
Main page: [[Use the LEDs#LED_Color_Registers_on_the_K_and_K2]]
{| class="wikitable"
{| class="wikitable"
|+F256k Series LEDs
!MMU
!MMU
!Flat
!Flat
Line 1,643: Line 1,650:
!0
!0
|-
|-
|$D6A7 - $D6A9
|$D6A7
|
|$F0:16A7
|W
|W
|
|
| colspan="8" |Power LED color (BGR)
| colspan="8" |Power LED color ([[IO Pages#BGR|BGR]])
|-
|-
|$D6AA - $D6AC
|$D6AA
|
|$F0:16AA
|W
|W
|
|
| colspan="8" |Media LED color (BGR)
| colspan="8" |Media LED color ([[IO Pages#BGR|BGR]])
|-
|-
|$D6AD - $D6AF
|$D6AD
|
|$F0:16AD
|W
|W
|
|
| colspan="8" |Shift LED color (BGR)
| colspan="8" |Shift LED color ([[IO Pages#BGR|BGR]])
|}
|}
====== $D6A7: Machine ID and FPGA Core Versions ======
{| class="wikitable"
{| class="wikitable"
|+Machine ID and FPGA Core Versions
!MMU
!MMU
!Flat
!Flat
Line 1,677: Line 1,685:
|-
|-
|$D6A7
|$D6A7
|
|$F0:16A7
|R
|R
|MID
|MID
Line 1,683: Line 1,691:
|—
|—
|—
|—
| colspan="5" |ID
| colspan="5" |[[MID codes for machine identification|Machine ID]]
|-
|-
|$D6A8
|$D6A8
|
|$F0:16A8
|R
|R
|PCBID0
|PCBID0
Line 1,692: Line 1,700:
|-
|-
|$D6A9
|$D6A9
|
|$F0:16A9
|R
|R
|PCBID1
|PCBID1
Line 1,698: Line 1,706:
|-
|-
|$D6AA
|$D6AA
|
|$F0:16AA
|R
|R
|CHSV
|CHSV
Line 1,704: Line 1,712:
|-
|-
|$D6AC
|$D6AC
|
|$F0:16AC
|R
|R
|CHV
|CHV
Line 1,710: Line 1,718:
|-
|-
|$D6AE
|$D6AE
|
|$F0:16AE
|R
|R
|CHN
|CHN
| colspan="8" |VICKY number in BCD (16-bit)
| colspan="8" |VICKY number in BCD (16-bit)
|}
|}
====== $D6E0: Mouse Pointer Control ======
{| class="wikitable"
{| class="wikitable"
|+Mouse Pointer Control
!MMU
!MMU
!Flat
!Flat
Line 1,731: Line 1,740:
|-
|-
|$D6E0
|$D6E0
|
|$F0:16E0
|W
|W
|
|
Line 1,744: Line 1,753:
|-
|-
|$D6E2
|$D6E2
|
|$F0:16E2
|RW
|RW
|
|
Line 1,750: Line 1,759:
|-
|-
|$D6E4
|$D6E4
|
|$F0:16E4
|RW
|RW
|
|
Line 1,756: Line 1,765:
|-
|-
|$D6E6
|$D6E6
|
|$F0:16E6
|W
|W
|
|
Line 1,762: Line 1,771:
|-
|-
|$D6E7
|$D6E7
|
|$F0:16E7
|W
|W
|
|
Line 1,768: Line 1,777:
|-
|-
|$D6E8
|$D6E8
|
|$F0:16E8
|W
|W
|
|
| colspan="8" |PS2_BYTE_2
| colspan="8" |PS2_BYTE_2
|}
|}
====== $D6EB: PCB Information ======
{| class="wikitable"
{| class="wikitable"
|+PCB Information
!MMU
!MMU
!Flat
!Flat
Line 1,789: Line 1,799:
|-
|-
|$D6EB
|$D6EB
|
|$F0:16EB
|R
|R
|PCBMA
|PCBMA
Line 1,795: Line 1,805:
|-
|-
|$D6EC
|$D6EC
|
|$F0:16EC
|R
|R
|PCBMI
|PCBMI
Line 1,801: Line 1,811:
|-
|-
|$D6ED
|$D6ED
|
|$F0:16ED
|R
|R
|PCBD
|PCBD
Line 1,807: Line 1,817:
|-
|-
|$D6EE
|$D6EE
|
|$F0:16EE
|R
|R
|PCBM
|PCBM
Line 1,813: Line 1,823:
|-
|-
|$D6EF
|$D6EF
|
|$F0:16EF
|R
|R
|PCBY
|PCBY
| colspan="8" |PCB Year (BCD)
| colspan="8" |PCB Year (BCD)
|}
|}
===== $D700: VS1053b (F256 Gen 2 only) =====
Main page: [[Use the VS1053b chip]]
{| class="wikitable"
{| class="wikitable"
|+Text mode CLUT
!MMU
!MMU
!Flat
!Flat
Line 1,833: Line 1,845:
!0
!0
|-
|-
|$D800 - $D83F
|$D700
|$F0:1700
|
|
|W
|SCI Control
| colspan="8" |Control the flow of information
|-
|$D701
|$F0:1701
|
|
| colspan="8" |Text foreground colors (16 × [[IO Pages#BGRx|BGRx]])
|SCI Address
| colspan="8" |Select to which VS1053b address to write to
|-
|-
|$D840 - $D87F
|$D702
|$F0:1702
|
|
|W
|SCI Data 1
| colspan="8" |First byte of data
|-
|$D703
|$F0:1703
|
|SCI Data 2
| colspan="8" |Second byte of data
|-
|$D704
|$F0:1704
|
|FIFO Count 1
| colspan="8" |First byte of the remaining byte count in the FIFO
|-
|$D705
|$F0:1705
|
|
| colspan="8" |Text background colors (16 × [[IO Pages#BGRx|BGRx]])
|FIFO Count 2
| colspan="8" |Second byte of the remaining byte count in the FIFO
|}
|}
===== $D800: Text Mode CLUT =====
{| class="wikitable"
{| class="wikitable"
|+Sprite Registers
!MMU
!MMU
!Flat
!Flat
Line 1,860: Line 1,897:
!0
!0
|-
|-
|$D900 - $DAFF
|$D800 - $D83F
|
|$F0:1800 - $F0:183F
|
|
| colspan="8" |64 × 8-byte Sprite Registers
|-
|
| +0
|W
|W
|
|
|—
| colspan="8" |Text foreground colors (16 × [[IO Pages#BGRx|BGRx]])
| colspan="2" |SIZE
| colspan="2" |LAYER
| colspan="2" |LUT
|ENABLE
|-
|-
|
|$D840 - $D87F
|
|$F0:1840 - $F0:187f
|
|SIZE
| colspan="8" |0: 32×32, 1: 24×24, 2: 16×16, 3: 8×8
|-
|
| +1
|W
|W
|
|
| colspan="8" |[[IO Pages#SRAM Address|SRAM Address]] of sprite pixels (24-bit)
| colspan="8" |Text background colors (16 × [[IO Pages#BGRx|BGRx]])
|-
|
| +4
|W
|
| colspan="8" |X position (16-bit)
|-
|
| +6
|W
|
| colspan="8" |Y position (16-bit)
|}
|}
===== $D880: NES/SNES Gamepads =====
Main page: [[Use the SNES/NES controllers]]
{| class="wikitable"
{| class="wikitable"
|+VIAs
!MMU
!MMU
!Flat
!Flat
Line 1,915: Line 1,926:
!0
!0
|-
|-
|$DB00
|$D880
|$F0:1880
|R
|NES_CTRL
|NES_TRIG
|DONE
|—
|—
|—
|MODE
|—
|NES_EN
|-
|
|
|
|
|VIA1
|W
| colspan="8" |Internal Keyboard VIA (F256k series only!)
|NES_CTRL
|NES_TRIG
|—
|—
|—
|—
|MODE
|—
|NES_EN
|-
|-
|$DC00
|$D884
|$F0:1884
|
|
|
|
|VIA0
| colspan="8" |Pad 0
| colspan="8" |Atari joystick VIA
|-
|$D886
|$F0:1886
|
|
| colspan="8" |Pad 1
|-
|-
|$D888
|$F0:1888
|
|
|
| +0
| colspan="8" |Pad 2
|RW
|IORB
| colspan="8" |Port B Data
|-
|-
|$D88A
|$F0:188A
|
|
| +1
|RW
|IORA
| colspan="8" |Port A Data
|-
|
|
| +2
| colspan="8" |Pad 3
|RW
|DDRB
| colspan="8" |Port B Data Direction Register
|-
|-
|
|
| +3
| +0
|RW
|DDRA
| colspan="8" |Port A Data Direction Register
|-
|
|
| +4
|Mode=0
|RW
|A
|T1C
|B
| colspan="8" |Timer 1 Counter (16-bit)
|SELECT
|START
|UP
|DOWN
|LEFT
|RIGHT
|-
|-
|
|
| +6
| +0
|RW
|T1L
| colspan="8" |Timer 1 Latch (16-bit)
|-
|
|
| +8
|Mode=1
|RW
|B
|T2C
|Y
| colspan="8" |Timer 2 Counter (16-bit)
|SELECT
|START
|UP
|DOWN
|LEFT
|RIGHT
|-
|-
|
|
| +A
| +1
|RW
|SDR
| colspan="8" |Serial Data Registers
|-
|
|
| +B
|Mode=1
|RW
|—
|ACR
|—
| colspan="2" |T1_CTRL
|
|T2_CTRL
|
| colspan="3" |SR_CTRL
|A
|PBL_EN
|X
|PAL_EN
|L
|R
|}
 
===== $D900: Sprites =====
{| class="wikitable"
!MMU
!Flat
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|-
|$D900 - $DAFF
|$F0:1900 - $F0:1AFF
|
|
|
| +C
| colspan="8" |64 × 8-byte Sprite Registers
|RW
|PCR
| colspan="3" |CB2_CTRL
|CB1_CTRL
| colspan="3" |CA1_CTRL
|CA1_CTRL
|-
|-
|
|
| +D
| +0
|RW
|W
|IFR
|
|IRQF
|
|T1F
| colspan="2" |SIZE
|T2F
| colspan="2" |LAYER
|CB1F
| colspan="2" |LUT
|CB2F
|ENABLE
|SRF
|CA1F
|CA2F
|-
|-
|
|
| +E
|
|RW
|
|IER
|SIZE
|SET
| colspan="8" |0: 32×32
|T1E
1: 24×24
|T2E
 
|CB1E
2: 16×16
|CB2E
 
|SRE
3: 8×8
|CA1E
|CA2E
|-
|-
|
|
| +F
| +1
|RW
|W
|IORA2
|
| colspan="8" |Port A Data (no handshake)
| colspan="8" |[[IO Pages#SRAM Address|SRAM Address]] of sprite pixels (24-bit)
|-
|
| +4
|W
|
| colspan="8" |X position (16-bit)
|-
|
| +6
|W
|
| colspan="8" |Y position (16-bit)
|}
|}
===== $DB00: Moar system =====
====== $DB00: VIAs ======
See: [[Keyboard raw codes]]
{| class="wikitable"
{| class="wikitable"
|+SD Card Controller
!MMU
!MMU
!Flat
!Flat
Line 2,041: Line 2,095:
!0
!0
|-
|-
|$DD00
|$DB00
|$F0:1B00
|
|
|RW
|VIA1
| colspan="8" |Internal Keyboard VIA (F256k series only!)
|-
|$DC00
|$F0:1C00
|
|
|SPI_BUSY
|VIA0
|
| colspan="8" |Atari joystick VIA
|—
|—
|—
|—
|SPI_CLK
|CS_EN
|-
|-
|$DD01
|
|
| +0
|RW
|RW
|
|IORB
| colspan="8" |SPI_DATA
| colspan="8" |Port B Data
|}
'''SPI_CLK''': 400MHz init clock when set, 12.5MHz standard clock when clear.
{| class="wikitable"
|+Integer Math Coprocessor
!MMU
!Flat
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|-
|$DE00 - $DE01
|
|
| +1
|RW
|RW
|MULU_A
|IORA
| colspan="8" |Multiplication A (Unsigned 16-bit)
| colspan="8" |Port A Data
|-
|-
|$DE00 - $DE02
|
|
| +2
|RW
|RW
|MULU_B
|DDRB
| colspan="8" |Multiplication B (Unsigned 16-bit)
| colspan="8" |Port B Data Direction Register
|-
|-
|$DE04 - $DE05
|
|RW
|DIVU_DEN
| colspan="8" |Division Denominator (Unsigned 16-bit)
|-
|$DE06 - $DE07
|
|RW
|DIVU_NUM
| colspan="8" |Division Numerator (Unsigned 16-bit)
|-
|$DE08 - $DE0B
|
|RW
|ADD_A
| colspan="8" |Addition A (Unsigned 32-bit)
|-
|$DE0C - $DE0F
|
|RW
|ADD_B
| colspan="8" |Addition B (Unsigned 32-bit)
|-
|
|
|
|
| colspan="8" |
|-
|$DE10 - $DE13
|
|
| +3
|RW
|DDRA
| colspan="8" |Port A Data Direction Register
|-
|
| +4
|RW
|T1C
| colspan="8" |Timer 1 Counter (16-bit)
|-
|
| +6
|RW
|T1L
| colspan="8" |Timer 1 Latch (16-bit)
|-
|
| +8
|RW
|T2C
| colspan="8" |Timer 2 Counter (16-bit)
|-
|
| +A
|RW
|SDR
| colspan="8" |Serial Data Registers
|-
|
| +B
|RW
|ACR
| colspan="2" |T1_CTRL
|T2_CTRL
| colspan="3" |SR_CTRL
|PBL_EN
|PAL_EN
|-
|
| +C
|RW
|PCR
| colspan="3" |CB2_CTRL
|CB1_CTRL
| colspan="3" |CA1_CTRL
|CA1_CTRL
|-
|
| +D
|RW
|IFR
|IRQF
|T1F
|T2F
|CB1F
|CB2F
|SRF
|CA1F
|CA2F
|-
|
| +E
|RW
|IER
|SET
|T1E
|T2E
|CB1E
|CB2E
|SRE
|CA1E
|CA2E
|-
|
| +F
|RW
|IORA2
| colspan="8" |Port A Data (no handshake)
|}
====== $DD00: SD Card Controllers ======
{| class="wikitable"
!MMU
!Flat
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|$DD00
|$F0:1D00
|
|
| colspan="8" |SD Card 0 (external)
|-
|$DD20
|$F0:1D20
|
|
| colspan="8" |SD Card 1 (internal)
|-
|
| +0
|RW
|
|SPI_BUSY
|—
|—
|—
|—
|—
|SPI_CLK
|CS_EN
|-
|
| +1
|RW
|
| colspan="8" |SPI_DATA
|}
'''SPI_CLK''': 400MHz init clock when set, 12.5MHz standard clock when clear.
====== $DD40: F256K2 Case LCD Screen ======
Main page: [[Use the K2 LCD]]
{| class="wikitable"
!MMU
!Flat
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|$DD40
|$F0:1D40
|
|LCD_CMD_CMD
| colspan="8" |Command
|-
|$DD41
|$F0:1D41
|
|LCD_CMD_DTA
| colspan="8" |Data
|-
|$DD42
|$F0:1D42
|
|LCD_PIX_LO
| colspan="3" |Green[2:0]
| colspan="5" |Blue
|-
|$DD43
|$F0:1D43
|
|LCD_PIX_HI
| colspan="5" |Red
| colspan="3" |Green[5:3]
|}
===== $DDA0: SAM2695 MIDI (F256 Gen 2 only) =====
Main page: [[Use the Sam2695 Dream MIDI chip]]
{| class="wikitable"
!MMU
!Flat
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|$DDA0
|$F0:1DA0
|R
|MIDI_STATUS
|TX_EMPTY
|RX_FULL
|—
|—
|—
|—
|—
|—
|-
|$DDA1
|$F0:1DA1
|RW
|MIDI_FIFO_DATA_PORT
| colspan="8" |Data
|-
|$DDA2
|$F0:1DA2
|
|MIDI_RXD_COUNT
| colspan="8" |Rx FIFO Data count (12-bit)
|-
|$DDA4
|$F0:1DA4
|
|MIDI_TXD_COUNT
| colspan="8" |Tx FIFO Data Count (12-bit)
|}
===== $DE00: Integer Math Coprocessor =====
{| class="wikitable"
!MMU
!Flat
!R/W
!Name
!7
!6
!5
!4
!3
!2
!1
!0
|-
|$DE00
|$F0:1E00
|RW
|MULU_A
| colspan="8" |Multiplication A (Unsigned 16-bit)
|-
|$DE02
|$F0:1E02
|RW
|MULU_B
| colspan="8" |Multiplication B (Unsigned 16-bit)
|-
|$DE04
|$F0:1E04
|RW
|DIVU_DEN
| colspan="8" |Division Denominator (Unsigned 16-bit)
|-
|$DE06
|$F0:1E06
|RW
|DIVU_NUM
| colspan="8" |Division Numerator (Unsigned 16-bit)
|-
|$DE08
|$F0:1E08
|RW
|ADD_A
| colspan="8" |Addition A (Unsigned 32-bit)
|-
|$DE0C
|$F0:1E0C
|RW
|ADD_B
| colspan="8" |Addition B (Unsigned 32-bit)
|-
|
|
|
|
| colspan="8" |
|-
|$DE10
|$F0:1E10
|RW
|RW
|MULU
|MULU
| colspan="8" |Multiplication A×B Result (Unsigned 32-bit)
| colspan="8" |Multiplication A×B Result (Unsigned 32-bit)
|-
|-
|$DE14 - $DE15
|$DE14
|
|$F0:1E14
|RW
|RW
|QUOU
|QUOU
| colspan="8" |Quotient of Num/Den (Unsigned 16-bit)
| colspan="8" |Quotient of Num/Den (Unsigned 16-bit)
|-
|-
|$DE16 - $DE17
|$DE16
|
|$F0:1E16
|RW
|RW
|REMU
|REMU
| colspan="8" |Remainder of Num/Den (Unsigned 16-bit)
| colspan="8" |Remainder of Num/Den (Unsigned 16-bit)
|-
|-
|$DE18 - $DE1B
|$DE18
|
|$F0:1E18
|RW
|RW
|ADD_R
|ADD_R
Line 2,143: Line 2,428:
|}
|}
Multiplication, division, and addition operations are completely independent of each other. Results are available immediately.
Multiplication, division, and addition operations are completely independent of each other. Results are available immediately.
===== $DF00: DMA Controller =====
{| class="wikitable"
{| class="wikitable"
|+DMA Controller
!MMU
!MMU
!Flat
!Flat
Line 2,159: Line 2,445:
|-
|-
|$DF00
|$DF00
|
|$F0:1F00
|RW
|RW
|
|
|START
|START
|
|
|
|
|
|
|INT_EN
|INT_EN
|FILL
|FILL
Line 2,172: Line 2,458:
|-
|-
|$DF01
|$DF01
|
|$F0:1F01
|W
|W
|
|
Line 2,178: Line 2,464:
|-
|-
|$DF04
|$DF04
|
|$F0:1F04
|RW
|RW
|
|
Line 2,184: Line 2,470:
|-
|-
|$DF08
|$DF08
|
|$F0:1F08
|RW
|RW
|
|
Line 2,190: Line 2,476:
|-
|-
|$DF0C
|$DF0C
|
|$F0:1F0C
|RW
|RW
|
|
| colspan="8" |Count (24-bit, not 2D mode)
| colspan="8" |Count (24-bit, not 2D mode)
|-
|-
|$DF0C
|
|
|
|RW
|RW
Line 2,202: Line 2,488:
|-
|-
|$DF0E
|$DF0E
|
|$F0:1F0E
|RW
|RW
|
|
Line 2,208: Line 2,494:
|-
|-
|$DF10
|$DF10
|
|$F0:1F10
|RW
|RW
|
|
Line 2,214: Line 2,500:
|-
|-
|$DF12
|$DF12
|
|$F0:1F12
|RW
|RW
|
|
Line 2,221: Line 2,507:


== IO Page 1 ==
== IO Page 1 ==
====== $C000: Text Mode Font Sets ======
{| class="wikitable"
{| class="wikitable"
|+Text Mode Font Sets
!MMU
!MMU
!Flat
!Flat
Line 2,242: Line 2,529:
|}
|}
Characters are 8×8 pixels. Each byte is an 8-pixel row of bits, with MSB at the left. 8 rows top to bottom.
Characters are 8×8 pixels. Each byte is an 8-pixel row of bits, with MSB at the left. 8 rows top to bottom.
====== $D000: Graphics CLUTs ======
{| class="wikitable"
{| class="wikitable"
|+Graphics CLUTS
!MMU
!MMU
!Flat
!Flat
Line 2,275: Line 2,563:
|}
|}
== IO Page 2 ==
== IO Page 2 ==
====== $C000: Text Screen Character Matrix ======
{| class="wikitable"
{| class="wikitable"
|+
!MMU
!MMU
!Flat
!Flat
Line 2,294: Line 2,583:


== IO Page 3 ==
== IO Page 3 ==
====== $C000: Text Screen Color Matrix ======
{| class="wikitable"
{| class="wikitable"
|+
!MMU
!MMU
!Flat
!Flat

Latest revision as of 23:44, 9 October 2025

More detailed information is found in the Manuals.

Notes

SRAM Address: Raw addresses for the system SRAM chip. The VICKY can only address the system SRAM (for now, DDR3 support coming). The 1st gen hardware has 512kB (19-bit space), while the 2nd gen has 2MB (21-bit space). The 24-bit pointers used are direct addresses into the SRAM chip, regardless of how the 2MB is mapped to the CPU's/MMU's address space. For instance, Core2x has 4 separate 512kB banks at non-consecutive addresses; these 4 banks are all linear+consecutive in the SRAM, and that view must be addressed here instead of its 24-bit CPU-visible addresses.

Model names: Certain features are only available on certain models, and these terms are used exactly. For instance, "F256Jr" means exactly the 1st gen Jr, not the entire Jr line.

BGR: A 3-byte color entry in Blue, Green, Red order.

BGRx: A 4-byte aligned color entry in Blue, Green, Red order, with the 4th byte unused.

IO Page 0

$C000 Gamma Lookup
MMU Flat R/W Name Description
$C000 - $C0FF $F0:0000 - $F0:00FF Blue gamma conversion table
$C400 - $C4FF $F0:0400 - $F0:04FF Green gamma conversion table
$C800 - $C8FF $F0:0800 - $F0:08FF Red gamma conversion table
$CC00: Mouse Pointer Bitmap

See: Use the PS/2 Mouse

MMU Flat R/W Name Description
$CC00 - $CCFF $F0:0C00 - $F0:0CFF Mouse pointer bitmap (16×16 greyscale bytes)
$D000: VICKY Config
$D000: Master Control Registers
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D000 $F0:1000 RW MSTR_CTRL_0 GAMMA SPRITE TILE BITMAP GRAPH OVRLY TEXT
$D001 $F0:1001 RW MSTR_CTRL_1 FON_SET FON_OVLY MON_SLP DBL_Y DBL_X CLK_70

TEXT: Enable text layer

OVRLY: Overlay text on graphics, by making text background transparent. See FON_OVLY

GRAPH: Enable graphics layers (tile, sprites, bitmaps)

BITMAP: Enable bitmap layers (if GRAPH is also set)

TILE: Enable tile layers (if GRAPH is also set)

SPRITE: Enable sprite layers (if GRAPH is also set)

GAMMA: Enable gamma correction

CLK_70: Enable 400p70, else 480p60

DBL_X, DBL_Y: Double text mode character width & height

MON_SLP: Turn off monitor SYNC, putting it into sleep mode

FON_OVLY: Only BG color 0 is transparent in OVRLY mode. Else, all BG colors are transparent.

FON_SET: Chooses font set 0 or 1

$D002: Layers
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D002 $F0:1002 RW Layer 1 Layer 0
$D003 $F0:1003 RW Layer 2
Values 0-2: Bitmap 0-2

4-6: Tilemap 0-2

$D004: Border
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D004 $F0:1004 RW BRDR_CTRL SCROLL_X ENABLE
$D005 $F0:1005 RW BRDR_BLUE Border color Blue component
$D006 $F0:1006 RW BRDR_GREEN Border color Green component
$D007 $F0:1007 RW BRDR_RED Border color Red component
$D008 $F0:1008 RW BRDR_WIDTH SIZE_X
$D009 $F0:1009 RW BRDR_HEIGHT SIZE_Y
$D00D: Background
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D00D $F0:100D RW BGND_BLUE Background color Blue component
$D00E $F0:100E RW BGND_GREEN Background color Green component
$D00F $F0:100F RW BGND_RED Background color Red component
$D010: Text Cursor
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D010 $F0:1010 RW CCR FLASH_DIS RATE ENABLE
RATE 0: 1 second

1: 1/2 second 2: 1/4 second 3: 1/8 second

$D012 $F0:1012 RW CCH Cursor character code
$D014 $F0:1014 RW CURX Cursor X position (16-bit)
$D016 $F0:1016 RW CURY Cursor Y position (16-bit)
$D018: Raster
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D018 $F0:1018 R RAST_COL Raster current column (12-bit)
$D01A $F0:101A R RAST_ROW Raster current row (12-bit)
$D018 $F0:1018 W LINT_CTRL ENABLE
$D019 $F0:1019 W LINT_L Line interrupt line (12-bit)
$D100: Bitmaps
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D100 $F0:1100 Bitmap 0
$D108 $F0:1108 Bitmap 1
$D110 $F0:1110 Bitmap 2
+0 RW CLUT ENABLE
+1 RW SRAM Address of pixels (24-bit)
$D200: Tilemaps
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D200 $F0:1200 Tilemap 0
$D20C $F0:120C Tilemap 1
$D218 $F0:1218 Tilemap 2
+$00 W TILE_SIZE_8 ENABLE
+$01 W SRAM Address of tile map entries (24-bit)
+$04 W MAP_SIZE_X (8-bit)
+$06 W MAP_SIZE_Y (8-bit)
+$08 W X[3:0] SSX
+$09 W X[9:4]
+$0A W Y[3:0] SSY
+$0B W Y[7:4]
$D280: Tilesets
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D280 $F0:1280 Tileset 0
$D284 $F0:1284 Tileset 1
$D288 $F0:1288 Tileset 2
$D28C $F0:128C Tileset 3
$D290 $F0:1290 Tileset 4
$D294 $F0:1294 Tileset 5
$D298 $F0:1298 Tileset 6
$D29C $F0:129C Tileset 7
+0 W SRAM Address of tile pixels (24-bit)
+3 W SQUARE
$D400: Sound
$D400: SID chips
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D400 $F0:1400 Left SID
$D500 $F0:1500 Right SID
+$00 W Voice 1 Frequency (16-bit)
+$02 W Pulse width (12-bit)
+$04 W NOISE PULSE SAW TRI TEST RING SYNC GATE
+$05 W ATTACK DELAY
+$06 W SUSTAIN RELEASE
+$07 W Voice 2 Frequency (16-bit)
+$09 W Pulse width (12-bit)
+$0B W NOISE PULSE SAW TRI TEST RING SYNC GATE
+$0C W ATTACK DELAY
+$0D W SUSTAIN RELEASE
+$0E W Voice 3 Frequency (16-bit)
+$10 W Pulse width (12-bit)
+$12 W NOISE PULSE SAW TRI TEST RING SYNC GATE
+$13 W ATTACK DELAY
+$14 W SUSTAIN RELEASE
+$15 W Misc FC[2:0]
+$16 W FC[10:3]
+$17 W RESONANCE EXT FILTV3 FILTV2 FILTV1
+$18 W MUTEV3 HIGH BAND LOW VOLUME
$D580: OPL3 (NOT on F256Jr!)

Main page: Use the OPL3 YMF262

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D580 $F0:1580 W Address registers for ports $000 - $0FF
$D581 $F0:1581 W Data registers for all ports
$D582 $F0:1582 W Address register for ports $100 - $1FF
$D600: PSGs

Main page: Use the PSG

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D600 $F0:1600 PSG Left
$D608 $F0:1608 PSG Left + Right
$D610 $F0:1610 PSG Right

Note the stereo separation is controlled with the PSG_ST flag.

$D620: CODEC

Main page: Use the CODEC

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D620 $F0:1620 W DATA[7:0]
$D621 $F0:1621 W REGISTER DATA[8]
$D622 $F0:1622 R BUSY
W START
$D630: System
$D630: UART
MMU Flat R/W Name 7 6 5 4 3 2 1 0
DLAB = 0
$D630 $F0:1630 R RXD RX_DATA
W TXR TX_DATA
$D631 $F0:1631 RW IER STAT ERR TXE RXA
DLAB = 1
$D630 $F0:1630 RW DL DIV (16-bit)
$D632 $F0:1632 R IIR FIFO FIFO64 STATE /PENDING
W FCR RXT FIFO64 DMA TXR RXR FIFOE
$D633 $F0:1633 RW LCR DLAB PARITY STOP DATA
$D640: PS/2

See: Use the PS/2 Mouse

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D640 $F0:1640 RW PS2_CTRL MCLR KCLR M_WR K_WR
$D641 $F0:1641 RW PS2_OUT Data to keyboard
$D642 $F0:1642 R KBD_IN Data in from keyboard FIFO
$D643 $F0:1643 R MS_IN Data in from mouse FIFO
$D644 $F0:1644 R PS2_STAT K_AK K_NK M_AK M_NK MEMP KEMP
$D650: Timers
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D650 $F0:1650 W T0_CTR UP LD CLR EN
R T0_STAT EQ
$D651 $F0:1651 RW T0_VAL VAL (24-bit)
$D654 $F0:1654 RW T0_CMP_CTR RELD RECLR
$D655 $F0:1655 RW T0_CMP CMP (24-bit)
$D658 $F0:1658 W T1_CTR UP LD CLR EN
R T1_STAT EQ
$D659 $F0:1659 RW T1_VAL VAL (24-bit)
$D65C $F0:165C RW T1_CMP_CTR RELD RECLR
$D65D $F0:165D RW T1_CMP CMP (24-bit)
$D660: Interrupts

Main page: IRQ, IRQ Programming

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D660 $F0:1660 INT_PENDING Per-interrupt flags (24-bit)
$D664 $F0:1664 INT_POLARITY Per-interrupt flags (24-bit)
$D668 $F0:1668 INT_EDGE Per-interrupt flags (24-bit)
$D66C $F0:166C INT_MASK Per-interrupt flags (24-bit)
+0 & $01 INT_VKY_SOF Start of Frame interrupt (beginning of VSYNC)
+0 & $02 INT_VKY_SOL Start of Line interrupt
+0 & $04 INT_PS2_KBD PS/2 keyboard event
+0 & $08 INT_PS2_MOUSE PS/2 mouse event
+0 & $10 INT_TIMER_0 TIMER0 has reached its target value
+0 & $20 INT_TIMER_1 TIMER1 has reached its target value
+0 & $80 INT_CARTRIDGE Interrupt asserted from cartridge port
+1 & $01 INT_UART The UART is ready to receive or send data
+1 & $10 INT_RTC Interrupt from real time clock chip
+1 & $20 INT_VIA0 Event from the joystick VIA chip
+1 & $40 INT_VIA1 Event from the keyboard VIA chip (F256k Series Only!)
+1 & $80 INT_SDC_INS SD Card has been inserted
+2 & $01 IEC_DATA_i IEC data in
+2 & $02 IEC_CLK_i IEC clock in
+2 & $04 IEC_ATN_i IEC attention in
+2 & $08 IEC_SREQ_i IEC service request in
$D670: DIP Switches

Main page: DIP switches

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D670 $F0:1670 R GAMMA USER2 USER1 USER0 BOOT
$D680: IEC
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D680 $F0:1680 R IEC_I SRQ_i ATN_i CLK_i DAT_i
$D681 $F0:1681 RW IEC_O SRQ_o RST_o NMI_EN ATN_o CLK_o DAT_o
$D690: RTC
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D690 $F0:1690 RW Seconds 0 10s digit 1s digit
$D691 $F0:1691 RW Seconds Alarm 0 10s digit 1s digit
$D692 $F0:1692 RW Minutes 0 10s digit 1s digit
$D693 $F0:1693 RW Minutes Alarm 0 10s digit 1s digit
$D694 $F0:1694 RW Hours AM/PM 0 10s digit 1s digit
$D695 $F0:1695 RW Hours Alarm AM/PM 0 10s digit 1s digit
$D696 $F0:1696 RW Days 0 0 10s digit 1s digit
$D697 $F0:1697 RW Days Alarm 0 0 10s digit 1s digit
$D698 $F0:1698 RW Day of Week 0 0 0 0 0 1s digit
$D699 $F0:1699 RW Month 0 0 0 10s digit 1s digit
$D69A $F0:169A RW Year 10s digit 1s digit
$D69B $F0:169B RW Rates 0 WD RS
$D69C $F0:169C RW Enables 0 0 0 0 AIE PIE PWRIE ABE
$D69D $F0:169D RW Flags 0 0 0 0 AF PF PWRF BVF
$D69E $F0:169E RW Control 0 0 0 0 UTI STOP 12/24 DSE
$D69F $F0:169F RW Century 10s digit 1s digit
$D6A0: System Control Registers

Main page: Use the LEDs

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D6A0 $F0:16A0 W SYS0 RESET CAP_EN BUZZ L1 L0 SD_L PWR_L
R SYS0 SD_WP SD_CD BUZZ L1 L0 SD_L PWR_L
$D6A1 $F0:16A1 RW SYS1 L1_RATE L0_RATE SID_ST PSG_ST L1_MN L0_MN
$D6A7: F256k Series LEDs

Main page: Use the LEDs#LED_Color_Registers_on_the_K_and_K2

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D6A7 $F0:16A7 W Power LED color (BGR)
$D6AA $F0:16AA W Media LED color (BGR)
$D6AD $F0:16AD W Shift LED color (BGR)
$D6A7: Machine ID and FPGA Core Versions
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D6A7 $F0:16A7 R MID Machine ID
$D6A8 $F0:16A8 R PCBID0 ASCII character 0: "B" (See also $D6EB)
$D6A9 $F0:16A9 R PCBID1 ASCII character 1: "0"
$D6AA $F0:16AA R CHSV VICKY sub-version in BCD (16-bit)
$D6AC $F0:16AC R CHV VICKY version in BCD (16-bit)
$D6AE $F0:16AE R CHN VICKY number in BCD (16-bit)
$D6E0: Mouse Pointer Control
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D6E0 $F0:16E0 W MODE EN
$D6E2 $F0:16E2 RW X (16-bit)
$D6E4 $F0:16E4 RW Y (16-bit)
$D6E6 $F0:16E6 W PS2_BYTE_0
$D6E7 $F0:16E7 W PS2_BYTE_1
$D6E8 $F0:16E8 W PS2_BYTE_2
$D6EB: PCB Information
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D6EB $F0:16EB R PCBMA PCB Major Rev (ASCII)
$D6EC $F0:16EC R PCBMI PCB Minor Rev (ASCII)
$D6ED $F0:16ED R PCBD PCB Day (BCD)
$D6EE $F0:16EE R PCBM PCB Month (BCD)
$D6EF $F0:16EF R PCBY PCB Year (BCD)
$D700: VS1053b (F256 Gen 2 only)

Main page: Use the VS1053b chip

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D700 $F0:1700 SCI Control Control the flow of information
$D701 $F0:1701 SCI Address Select to which VS1053b address to write to
$D702 $F0:1702 SCI Data 1 First byte of data
$D703 $F0:1703 SCI Data 2 Second byte of data
$D704 $F0:1704 FIFO Count 1 First byte of the remaining byte count in the FIFO
$D705 $F0:1705 FIFO Count 2 Second byte of the remaining byte count in the FIFO
$D800: Text Mode CLUT
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D800 - $D83F $F0:1800 - $F0:183F W Text foreground colors (16 × BGRx)
$D840 - $D87F $F0:1840 - $F0:187f W Text background colors (16 × BGRx)
$D880: NES/SNES Gamepads

Main page: Use the SNES/NES controllers

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D880 $F0:1880 R NES_CTRL NES_TRIG DONE MODE NES_EN
W NES_CTRL NES_TRIG MODE NES_EN
$D884 $F0:1884 Pad 0
$D886 $F0:1886 Pad 1
$D888 $F0:1888 Pad 2
$D88A $F0:188A Pad 3
+0 Mode=0 A B SELECT START UP DOWN LEFT RIGHT
+0 Mode=1 B Y SELECT START UP DOWN LEFT RIGHT
+1 Mode=1 A X L R
$D900: Sprites
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$D900 - $DAFF $F0:1900 - $F0:1AFF 64 × 8-byte Sprite Registers
+0 W SIZE LAYER LUT ENABLE
SIZE 0: 32×32

1: 24×24

2: 16×16

3: 8×8

+1 W SRAM Address of sprite pixels (24-bit)
+4 W X position (16-bit)
+6 W Y position (16-bit)
$DB00: Moar system
$DB00: VIAs

See: Keyboard raw codes

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$DB00 $F0:1B00 VIA1 Internal Keyboard VIA (F256k series only!)
$DC00 $F0:1C00 VIA0 Atari joystick VIA
+0 RW IORB Port B Data
+1 RW IORA Port A Data
+2 RW DDRB Port B Data Direction Register
+3 RW DDRA Port A Data Direction Register
+4 RW T1C Timer 1 Counter (16-bit)
+6 RW T1L Timer 1 Latch (16-bit)
+8 RW T2C Timer 2 Counter (16-bit)
+A RW SDR Serial Data Registers
+B RW ACR T1_CTRL T2_CTRL SR_CTRL PBL_EN PAL_EN
+C RW PCR CB2_CTRL CB1_CTRL CA1_CTRL CA1_CTRL
+D RW IFR IRQF T1F T2F CB1F CB2F SRF CA1F CA2F
+E RW IER SET T1E T2E CB1E CB2E SRE CA1E CA2E
+F RW IORA2 Port A Data (no handshake)
$DD00: SD Card Controllers
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$DD00 $F0:1D00 SD Card 0 (external)
$DD20 $F0:1D20 SD Card 1 (internal)
+0 RW SPI_BUSY SPI_CLK CS_EN
+1 RW SPI_DATA

SPI_CLK: 400MHz init clock when set, 12.5MHz standard clock when clear.

$DD40: F256K2 Case LCD Screen

Main page: Use the K2 LCD

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$DD40 $F0:1D40 LCD_CMD_CMD Command
$DD41 $F0:1D41 LCD_CMD_DTA Data
$DD42 $F0:1D42 LCD_PIX_LO Green[2:0] Blue
$DD43 $F0:1D43 LCD_PIX_HI Red Green[5:3]
$DDA0: SAM2695 MIDI (F256 Gen 2 only)

Main page: Use the Sam2695 Dream MIDI chip

MMU Flat R/W Name 7 6 5 4 3 2 1 0
$DDA0 $F0:1DA0 R MIDI_STATUS TX_EMPTY RX_FULL
$DDA1 $F0:1DA1 RW MIDI_FIFO_DATA_PORT Data
$DDA2 $F0:1DA2 MIDI_RXD_COUNT Rx FIFO Data count (12-bit)
$DDA4 $F0:1DA4 MIDI_TXD_COUNT Tx FIFO Data Count (12-bit)
$DE00: Integer Math Coprocessor
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$DE00 $F0:1E00 RW MULU_A Multiplication A (Unsigned 16-bit)
$DE02 $F0:1E02 RW MULU_B Multiplication B (Unsigned 16-bit)
$DE04 $F0:1E04 RW DIVU_DEN Division Denominator (Unsigned 16-bit)
$DE06 $F0:1E06 RW DIVU_NUM Division Numerator (Unsigned 16-bit)
$DE08 $F0:1E08 RW ADD_A Addition A (Unsigned 32-bit)
$DE0C $F0:1E0C RW ADD_B Addition B (Unsigned 32-bit)
$DE10 $F0:1E10 RW MULU Multiplication A×B Result (Unsigned 32-bit)
$DE14 $F0:1E14 RW QUOU Quotient of Num/Den (Unsigned 16-bit)
$DE16 $F0:1E16 RW REMU Remainder of Num/Den (Unsigned 16-bit)
$DE18 $F0:1E18 RW ADD_R Addition A+B Result (Unsigned 32-bit)

Multiplication, division, and addition operations are completely independent of each other. Results are available immediately.

$DF00: DMA Controller
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$DF00 $F0:1F00 RW START INT_EN FILL 2D ENABLE
$DF01 $F0:1F01 W Fill data byte
$DF04 $F0:1F04 RW Source SRAM Address (24-bit)
$DF08 $F0:1F08 RW Destination SRAM Address (24-bit)
$DF0C $F0:1F0C RW Count (24-bit, not 2D mode)
RW Width (16-bit, 2D mode)
$DF0E $F0:1F0E RW Height (16-bit, 2D mode)
$DF10 $F0:1F10 RW Source stride (16-bit, 2D mode)
$DF12 $F0:1F12 RW Destination stride (16-bit, 2D mode)

IO Page 1

$C000: Text Mode Font Sets
MMU Flat R/W Name Description
$C000 - $C7FF $F0:2000 - $F0:27FF Font set 0 (256 × 8-byte chars)
$C800 - $CFFF $F0:2800 - $F0:2FFF Font set 1 (256 × 8-byte chars)

Characters are 8×8 pixels. Each byte is an 8-pixel row of bits, with MSB at the left. 8 rows top to bottom.

$D000: Graphics CLUTs
MMU Flat R/W Name Description
$D000 - $D3FF $F0:3000 - $F0:33FF Graphics CLUT 0 (256 × BGRx)
$D400 - $D7FF $F0:3400 - $F0:37FF Graphics CLUT 1 (256 × BGRx)
$D800 - $DBFF $F0:3800 - $F0:3BFF Graphics CLUT 2 (256 × BGRx)
$DC00 - $DFFF $F0:3C00 - $F0:3FFF Graphics CLUT 3 (256 × BGRx)

IO Page 2

$C000: Text Screen Character Matrix
MMU Flat R/W Name Description
$C000 - $DFFF $F0:4000 - $F0:5FFF RW Text screen character matrix

1 byte per character, 40 or 80 characters per row, 25|30|50|60 rows in the matrix. Each character byte refers to an entry in the currently selected font set.

80×60 characters uses 4800 ($12C0) bytes, which is only a bit more than half the 8k allocation.

IO Page 3

$C000: Text Screen Color Matrix
MMU Flat R/W Name 7 6 5 4 3 2 1 0
$C000 - $DFFF $F0:6000 - $F0:7FFF RW Text screen color matrix
FG color (0-15) BG color (0-15)

Exact same layout as the character matrix. One color matrix byte associates to one character matrix byte at the same offset.