IO Pages
From F256 Foenix
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: 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: 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
$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 | SCI Control | Control the flow of information | |||||||||
| $D701 | SCI Address | Select to which VS1053b address to write to | |||||||||
| $D702 | SCI Data 1 | First byte of data | |||||||||
| $D703 | SCI Data 2 | Second byte of data | |||||||||
| $D704 | FIFO Count 1 | First byte of the remaining byte count in the FIFO | |||||||||
| $D705 | 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 | R | NES_CTRL | NES_TRIG | DONE | — | — | — | MODE | — | NES_EN | |
| W | NES_CTRL | NES_TRIG | — | — | — | — | MODE | — | NES_EN | ||
| $D884 | Pad 0 | ||||||||||
| $D886 | Pad 1 | ||||||||||
| $D888 | Pad 2 | ||||||||||
| $D88A | 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 Controller
| MMU | Flat | R/W | Name | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| $DD00 | $F0:1D00 | RW | SPI_BUSY | — | — | — | — | — | SPI_CLK | CS_EN | |
| $DD01 | $F0:1D01 | 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 (F256K series only)
Main page: Use the Sam2695 Dream MIDI chip
| MMU | Flat | R/W | Name | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| $DDA0 | R | MIDI_STATUS | TX_EMPTY | RX_FULL | — | — | — | — | — | — | |
| $DDA1 | RW | MIDI_FIFO_DATA_PORT | Data | ||||||||
| $DDA2 | MIDI_RXD_COUNT | Rx FIFO Data count (12-bit) | |||||||||
| $DDA4 | 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.
