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iomap.txt
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iomap.txt
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C64 $0000000 6510/45GS10 CPU port DDR
C64 $0000001 6510/45GS10 CPU port data
GS $8000000 - $FEFFFFF Slow RAM (127MB)
C64 $D000 VIC-II sprite 0 horizontal position
C64 $D001 VIC-II sprite 1 horizontal position
C64 $D002 VIC-II sprite 2 horizontal position
C64 $D003 VIC-II sprite 3 horizontal position
C64 $D004 VIC-II sprite 4 horizontal position
C64 $D005 VIC-II sprite 5 horizontal position
C64 $D006 VIC-II sprite 6 horizontal position
C64 $D007 VIC-II sprite 7 horizontal position
C64 $D008 VIC-II sprite 0 vertical position
C64 $D009 VIC-II sprite 1 vertical position
C64 $D00A VIC-II sprite 2 vertical position
C64 $D00B VIC-II sprite 3 vertical position
C64 $D00C VIC-II sprite 4 vertical position
C64 $D00D VIC-II sprite 5 vertical position
C64 $D00E VIC-II sprite 6 vertical position
C64 $D00F VIC-II sprite 7 vertical position
C64 $D010 VIC-II sprite horizontal position MSBs
C64 $D011 VIC-II control register
C64 $D011.2-0 VIC-II 24/25 vertical smooth scroll
C64 $D011.5 VIC-II 24/25 row select
C64 $D011.5 VIC-II disable display
C64 $D011.5 VIC-II text mode
C64 $D011.6 VIC-II extended background mode
C64 $D011.7 VIC-II raster compare bit 8
C64 $D012 VIC-II raster compare bits 0 to 7
C64 $D013 Coarse horizontal beam position (was lightpen X)
C64 $D014 Coarse vertical beam position (was lightpen Y)
C64 $D015 VIC-II sprite enable bits
C64 $D016 VIC-II control register
C64 $D016.2-0 VIC-II horizontal smooth scroll
C64 $D016.3 VIC-II 38/40 column select
C64 $D016.4 VIC-II Multi-colour mode
C64 $D017 VIC-II sprite enable bits
C64 $D018 VIC-II RAM addresses
C64 $D018.3-1 VIC-II character set address location (*1KB)
C64 $D018.7-4 VIC-II screen address (*1KB)
C64 $D019 VIC-II IRQ control
C64 $D019.0 VIC-II raster compare indicate or acknowledge
C64 $D019.1 VIC-II sprite:bitmap collision indicate or acknowledge
C64 $D019.2 VIC-II sprite:sprite collision indicate or acknowledge
C64 $D01A compatibility IRQ mask bits
C64 $D01A.2 VIC-II mask raster IRQ
C64 $D01A.2 VIC-II mask sprite:bitmap colission IRQ
C64 $D01A.2 VIC-II mask sprite:sprite colission IRQ
C64 $D01B VIC-II sprite background priority bits
C64 $D01C VIC-II sprite multicolour enable bits
C64 $D01D VIC-II sprite horizontal expansion enable bits
C64 $D01E VIC-II sprite/sprite collision indicate bits
C64 $D01E sprite/sprite collissions
C64 $D01F VIC-II sprite/sprite collision indicate bits
C64 $D01F sprite/sprite collissions
C64 $D020 Border colour
C64 $D020.3-0 VIC-II display border colour (16 colour)
C65 $D020.7-0 VIC-III/IV display border colour (256 colour)
C64 $D021 Screen colour
C64 $D021.3-0 VIC-II screen colour (16 colour)
C65 $D021.7-0 VIC-III/IV screen colour (256 colour)
C64 $D022 VIC-II multi-colour 1
C64 $D022.3-0 VIC-II multi-colour 1 (16 colour)
C65 $D022.7-0 VIC-III/IV multi-colour 1 (256 colour)
C64 $D023 VIC-II multi-colour 2
C64 $D023.3-0 VIC-II multi-colour 2 (16 colour)
C65 $D023.7-0 VIC-III/IV multi-colour 2 (256 colour)
C64 $D024 VIC-II multi-colour 3
C64 $D024.3-0 VIC-II multi-colour 3 (16 colour)
C65 $D024.7-0 VIC-III/IV multi-colour 3 (256 colour)
C64 $D025 VIC-II/III/IV sprite multi-colour 0 (always 256 colour)
C64 $D026 VIC-II/III/IV sprite multi-colour 1 (always 256 colour)
C64 $D027 VIC-II sprite 0 colour (always 256 colour)
C64 $D028 VIC-II sprite 1 colour (always 256 colour)
C64 $D029 VIC-II sprite 2 colour (always 256 colour)
C64 $D02A VIC-II sprite 3 colour (always 256 colour)
C64 $D02B VIC-II sprite 4 colour (always 256 colour)
C64 $D02C VIC-II sprite 5 colour (always 256 colour)
C64 $D02D VIC-II sprite 6 colour (always 256 colour)
C64 $D02E VIC-II sprite 7 colour (always 256 colour)
C65 $D02F VIC-III KEY register for unlocking extended registers.
GS $D02F Write $47 then $53 to enable C65GS/VIC-IV IO registers
C65 $D02F Write $A5 then $96 to enable C65/VIC-III IO registers
C65 $D02F Write anything else to return to C64/VIC-II IO map
C64 $D030 C128 2MHz emulation
C65 $D030 VIC-III Control Register A
C64 $D030.0 2MHz select (not yet functional)
C65 $D030.0 2nd KB of colour RAM @ $DC00-$DFFF
C65 $D030.1 VIC-III EXT SYNC (not implemented)
C65 $D030.2 Use PALETTE ROM or RAM entries for colours 0 - 15
C65 $D030.3 Map C65 ROM @ $8000
C65 $D030.4 Map C65 ROM @ $A000
C65 $D030.5 Map C65 ROM @ $C000
C65 $D030.6 Select between C64 and C65 charset.
C65 $D030.7 Map C65 ROM @ $E000
C65 $D031 VIC-III Control Register B
C65 $D031.0 VIC-III INT(erlaced?) (not implemented)
C65 $D031.1 VIC-III MONO (not implemented)
C65 $D031.2 VIC-III H1280 (1280 horizontal pixels)
C65 $D031.3 VIC-III V400 (400 vertical pixels)
C65 $D031.4 VIC-III Bit-Plane Mode (not implemented)
C65 $D031.5 VIC-III Enable extended attributes and 8 bit colour entries
C65 $D031.6 C65 FAST mode (~3.5MHz)
C65 $D031.7 VIC-III H640 (640 horizontal pixels)
C65 $D032 - Bitplane enable bits
C65 $D033 - Bitplane 0 address
C65 $D033-$D03A - VIC-III Bitplane addresses
C65 $D034 - Bitplane 1 address
C65 $D035 - Bitplane 2 address
C65 $D036 - Bitplane 3 address
C65 $D037 - Bitplane 4 address
C65 $D038 - Bitplane 5 address
C65 $D039 - Bitplane 6 address
C65 $D03A - Bitplane 7 address
C65 $D03B - Set bits to NOT bitplane contents
C65 $D03C - Bitplane X
C65 $D03D - Bitplane Y
GS $D040 DEPRECATED - VIC-IV characters per logical text row (LSB)
GS $D041 DEPRECATED - VIC-IV characters per logical text row (MSB)
GS $D042 DEPRECATED - VIC-IV horizontal hardware scale setting
GS $D043 DEPRECATED - VIC-IV vertical hardware scale setting
GS $D044 DEPRECATED - VIC-IV left border position (LSB)
GS $D045 DEPRECATED - VIC-IV left border position (MSB)
GS $D046 DEPRECATED - VIC-IV right border position (LSB)
GS $D047 DEPRECATED - VIC-IV right border position (MSB)
GS $D048 VIC-IV top border position (LSB)
GS $D049.3-0 VIC-IV top border position (MSB)
GS $D049.7-4 VIC-IV sprite 3-0 bitplane-modify-mode enables
GS $D04A VIC-IV bottom border position (LSB)
GS $D04B.3-0 VIC-IV bottom border position (MSB)
GS $D04B.7-4 VIC-IV sprite 7-4 bitplane-modify-mode enables
GS $D04C VIC-IV character generator horizontal position (LSB)
GS $D04D.3-0 VIC-IV character generator horizontal position (MSB)
GS $D04D.7-4 VIC-IV sprite 3-0 horizontal tile enables
GS $D04E VIC-IV character generator vertical position (LSB)
GS $D04F.3-0 VIC-IV character generator vertical position (MSB)
GS $D04F.7-4 VIC-IV sprite 7-4 horizontal tile enables
GS $D050 VIC-IV read horizontal position (LSB)
GS $D051 VIC-IV read horizontal position (MSB)
GS $D052 VIC-IV read physical raster/set raster compare (LSB)
GS $D053 VIC-IV read physical raster/set raster compare (MSB)
GS $D054 VIC-IV Control register C
GS $D054.0 VIC-IV enable 16-bit character numbers (two screen bytes per character)
GS $D054.1 VIC-IV enable full-colour mode for character numbers <=$FF
GS $D054.2 VIC-IV enable full-colour mode for character numbers >$FF
GS $D054.3 VIC-IV video output smear filter enable
GS $D054.6 VIC-IV/C65GS FAST mode (48MHz)
GS $D055 VIC-IV sprite extended height enable (one bit per sprite)
GS $D056 VIC-IV Sprite extended height size (sprite pixels high)
GS $D057 VIC-IV Sprite extended width enables
GS $D058 VIC-IV characters per logical text row (LSB)
GS $D059 VIC-IV characters per logical text row (MSB)
GS $D05A VIC-IV horizontal hardware scale setting
GS $D05B VIC-IV vertical hardware scale setting
GS $D05C VIC-IV left border position (LSB)
GS $D05D VIC-IV left border position (MSB)
GS $D05E VIC-IV right border position (LSB)
GS $D05F VIC-IV right border position (MSB)
GS $D060 VIC-IV screen RAM precise base address (bits 0 - 7)
GS $D061 VIC-IV screen RAM precise base address (bits 15 - 8)
GS $D062 VIC-IV screen RAM precise base address (bits 23 - 16)
GS $D063 VIC-IV screen RAM precise base address (bits 31 - 24)
GS $D064 VIC-IV colour RAM base address (bits 0 - 7)
GS $D065 VIC-IV colour RAM base address (bits 15 - 8)
GS $D068 VIC-IV character set precise base address (bits 0 - 7)
GS $D069 VIC-IV character set precise base address (bits 15 - 8)
GS $D06A VIC-IV character set precise base address (bits 23 - 16)
GS $D06B VIC-IV character set precise base address (bits 31 - 24)
GS $D06C VIC-IV sprite pointer address (bits 7 - 0)
GS $D06D VIC-IV sprite pointer address (bits 15 - 8)
GS $D06E VIC-IV sprite pointer address (bits 23 - 16)
GS $D06F VIC-IV sprite pointer address (bits 31 - 24)
GS $D070 VIC-IV palette bank selection
GS $D070.1-0 VIC-IV bitmap/text palette bank
GS $D070.3-2 VIC-IV sprite palette bank
GS $D070.5-4 VIC-IV bitmap/text palette bank
GS $D070.7-6 VIC-IV palette bank mapped at $D100-$D3FF
GS $D071 VIC-IV 16-colour bitplane enable flags
GS $D072 VIC-IV bitplanes horizontal start (in VIC-II pixels)
GS $D073 VIC-IV bitplanes vertical start (in VIC-II pixels)
GS $D07B VIC-IV hsync adjust
GS $D07C VIC-IV debug X position (LSB)
GS $D07D VIC-IV debug X position (MSB)
GS $D07E VIC-IV debug Y position (LSB)
GS $D07F VIC-IV debug X position (MSB)
C65 $D080 - F011 FDC control
C65 $D081 - F011 FDC command
C65 $D082 - F011 FDC Status A port (read only)
C65 $D083 - F011 FDC Status B port (read only)
C65 $D084 - F011 FDC track
C65 $D085 - F011 FDC data register
C65 $D085 - F011 FDC sector
C65 $D086 - F011 FDC side
C65 $D0A0-$D0FF - Reserved for C65 RAM Expansion Controller.
C65 $D100-$D1FF red palette values (reversed nybl order)
C65 $D200-$D2FF green palette values (reversed nybl order)
C65 $D300-$D3FF blue palette values (reversed nybl order)
C64 $D400-$D43F = right SID
C64 $D440-$D47F = left SID
C64 $D480-$D4FF = repeated images of SIDs
GS $D500-$D53F - 8x 64bit FPU input registers
GS $D540-$D5BF - 16x 64bit FPU intermediate/output registers (read only)
GS $D5C0 - FPU SIN/COS input register
GS $D5C1 - FPU SIN/COS output register
C65 $D600 C65 UART data register (read or write)
C65 $D601 C65 UART status register
C65 $D601.0 C65 UART RX byte ready flag (clear by reading $D600)
C65 $D601.1 C65 UART RX overrun flag (clear by reading $D600)
C65 $D601.2 C65 UART RX parity error flag (clear by reading $D600)
C65 $D601.3 C65 UART RX framing error flag (clear by reading $D600)
C65 $D602 C65 UART control register
C65 $D603 C65 UART baud rate divisor (low byte)
C65 $D604 C65 UART baud rate divisor (high byte)
C65 $D605 C65 UART interrupt mask register
C65 $D606 C65 UART interrupt flag register
C65 $D607 C65 UART 2-bit port data direction register (used for C65 keyboard)
C65 $D607 C65 UART 2-bit port data register (used for C65 keyboard)
GS $D609 MEGA65 extended UART control register
GS $D609.0 UART BAUD clock source: 1 = 7.09375MHz, 0 = 193.5MHz
GS $D60D DEBUG - Read hyper_trap_count: will be removed after debugging. XXX - Temporarily reading restore_up_ticks instead
GS $D60E PMOD port A on FPGA board (data bits)
GS $D60F PMOD port A on FPGA board (DDR)
GS $D630 - Read to obtain status of thumbnail generator.
GS $D630 - Write to reset port address for thumbnail generator
GS $D630-$D631 - Read-only hardware-generated thumbnail of display (accessible only in hypervisor mode)
GS $D630.6 - Thumbnail drawing was in progress.
GS $D630.7 - Thumbnail is valid if 1. Else there has not been a complete frame since elapsed without a trap to hypervisor mode, in which case the thumbnail may not reflect the current process.
GS $D631 - Read port for thumbnail generator
GS $D632 - Lower 8 bits of thumbnail buffer read address (TEMPORARY DEBUG REGISTER)
GS $D640 - Hypervisor A register storage
GS $D641 - Hypervisor X register storage
GS $D642 - Hypervisor Y register storage
GS $D643 - Hypervisor Z register storage
GS $D644 - Hypervisor B register storage
GS $D645 - Hypervisor SPL register storage
GS $D646 - Hypervisor SPH register storage
GS $D647 - Hypervisor P register storage
GS $D648 - Hypervisor PC-low register storage
GS $D649 - Hypervisor PC-high register storage
GS $D64A - Hypervisor MAPLO register storage (high bits)
GS $D64B - Hypervisor MAPLO register storage (low bits)
GS $D64C - Hypervisor MAPHI register storage (high bits)
GS $D64D - Hypervisor MAPHI register storage (low bits)
GS $D64E - Hypervisor MAPLO mega-byte number register storage
GS $D64F - Hypervisor MAPHI mega-byte number register storage
GS $D650 - Hypervisor CPU port $00 value
GS $D651 - Hypervisor CPU port $01 value
GS $D652 - Hypervisor VIC-IV IO mode
GS $D653 - Hypervisor DMAgic source MB
GS $D654 - Hypervisor DMAgic destination MB
GS $D655 - Hypervisor DMAGic list address bits 0-7
GS $D656 - Hypervisor DMAGic list address bits 15-8
GS $D657 - Hypervisor DMAGic list address bits 23-16
GS $D658 - Hypervisor DMAGic list address bits 27-24
GS $D659 - Hypervisor DDR RAM banking control
GS $D659.0-2 - Select which 16MB DDR RAM bank to make visible
GS $D659.7 - Enable DDR RAM banking
GS $D65D - Hypervisor current virtual page number (low byte)
GS $D65E - Hypervisor current virtual page number (mid byte)
GS $D65F - Hypervisor current virtual page number (high byte)
GS $D660 - Hypervisor virtual memory page 0 logical page low byte
GS $D661 - Hypervisor virtual memory page 0 logical page high byte
GS $D662 - Hypervisor virtual memory page 0 physical page low byte
GS $D663 - Hypervisor virtual memory page 0 physical page high byte
GS $D664 - Hypervisor virtual memory page 1 logical page low byte
GS $D665 - Hypervisor virtual memory page 1 logical page high byte
GS $D666 - Hypervisor virtual memory page 1 physical page low byte
GS $D667 - Hypervisor virtual memory page 1 physical page high byte
GS $D668 - Hypervisor virtual memory page 2 logical page low byte
GS $D669 - Hypervisor virtual memory page 2 logical page high byte
GS $D66A - Hypervisor virtual memory page 2 physical page low byte
GS $D66B - Hypervisor virtual memory page 2 physical page high byte
GS $D66C - Hypervisor virtual memory page 3 logical page low byte
GS $D66D - Hypervisor virtual memory page 3 logical page high byte
GS $D66E - Hypervisor virtual memory page 3 physical page low byte
GS $D66F - Hypervisor virtual memory page 3 physical page high byte
GS $D670 - Hypervisor GeoRAM base address (x MB) (write-only for
GS $D671 - Hypervisor GeoRAM address mask (applied to GeoRAM block
GS $D67C - Hypervisor write serial output to UART monitor (must wait atleast approx 4,000 cycles between writes to allow char to flush)
GS $D67D - Hypervisor watchdog register: writing any value clears the watch dog
GS $D67D.0 - Hypervisor C64 ROM source select (0=DDR,1=64KB colour RAM)
GS $D67D.1 - Hypervisor enable 32-bit JMP/JSR etc
GS $D67D.2 - Hypervisor write protect C65 ROM $20000-$3FFFF
GS $D67D.3 - Hypervisor enable ASC/DIN CAPS LOCK key to enable/disable CPU slow-down in C64/C128/C65 modes
GS $D67D.4 - Hypervisor force CPU to 48MHz for userland (userland can override via POKE0)
GS $D67D.5 - Hypervisor force CPU to 4502 personality, even in C64 IO mode.
GS $D67E - Hypervisor already-upgraded bit (sets permanently)
GS $D67F - Trigger trap to hypervisor
GS $D680 - SD controller status/command
GS $D681-$D684 - SD controller SD sector address
GS $D68B - Diskimage control flags
GS $D68B - F011 emulation control register
GS $D68B.0 - F011 disk 1 disk image enable
GS $D68B.1 - F011 disk 1 present
GS $D68B.2 - F011 disk 1 write protect
GS $D68B.3 - F011 disk 2 disk image enable
GS $D68B.4 - F011 disk 2 present
GS $D68B.5 - F011 disk 2 write protect
GS $D68C - Diskimage sector number (bits 0-7)
GS $D68C-$D68F - F011 disk 1 disk image address on SD card
GS $D68D - Diskimage sector number (bits 8-15)
GS $D68E - Diskimage sector number (bits 16-23)
GS $D68F - Diskimage sector number (bits 24-31)
GS $D690-$D693 - F011 disk 2 disk image address on SD card
GS $D6E0 Ethernet control
GS $D6E0.0 Clear to reset ethernet PHY
GS $D6E0.1-2 Read ethernet TX bits currently on the wire
GS $D6E0.3 Read ethernet RX data valid
GS $D6E0.4 Allow remote keyboard input via magic ethernet frames
GS $D6E1 - Ethernet interrupt and control register
GS $D6E1.0 reset ethernet PHY
GS $D6E1.1 - Set which RX buffer is memory mapped
GS $D6E1.2 - Indicate which RX buffer was most recently used
GS $D6E1.3 Enable real-time video streaming via ethernet
GS $D6E1.4 - Ethernet TX IRQ status
GS $D6E1.5 - Ethernet RX IRQ status
GS $D6E1.6 - Enable ethernet TX IRQ
GS $D6E1.7 - Enable ethernet RX IRQ
GS $D6E2 - TX Packet size (low byte)
GS $D6E2 Set low-order size of frame to TX
GS $D6E3 - TX Packet size (high byte)
GS $D6E3 Set high-order size of frame to TX
GS $D6E4 = $00 = Clear ethernet TX trigger (debug)
GS $D6E4 = $01 = Transmit packet
GS $D6E4 Ethernet command
GS $D6EE - Temperature sensor (lower byte)
GS $D6EF - Temperature sensor (upper byte)
GS $D6F0 - Read FPGA switches 0-7
GS $D6F1 - Read FPGA switches 8-15
GS $D6F2 - Read FPGA five-way buttons
GS $D6F3 - Accelerometer bit-bashing port
GS $D6F3 Accelerometer inputs
GS $D6F5 - Temperature sensor
GS $D6F5 Bit-bashed temperature sensor
GS $D6F6 - Keyboard scan code reader (lower byte)
GS $D6F7 - Keyboard scan code reader (upper nybl)
GS $D6F7 - microphone input (right)
GS $D6F8 - 8-bit digital audio out (left)
GS $D6F9.0 - Enable audio amplifier
GS $D6FA - 8-bit digital audio out (left)
GS $D6FB - microphone input (left)
GS $D6FF - Flash bit-bashing port
GS $D710-$D7FF - Enhanced sprite control registers (16 per enhanced sprite)
GS $D718-$D7FF - Enhanced sprite linear transform matricies. These allow for hardware rotation, flipping etc.
GS $D7x0-$D7x1 - Enhanced sprite X position in physical pixels (lower 12 bits)
GS $D7x1.4-7 - Enhanced sprite width (4 -- 64 pixels)
GS $D7x2-$D7x3 - Enhanced sprite Y position in physical pixels (16 bits)
GS $D7x3.4-7 - Enhanced sprite height (4 -- 64 pixels)
GS $D7x4 - Enhanced sprite data offset in its 4KB SpriteRAM (x16 bytes)
GS $D7x5 - Enhanced sprite foreground mask
GS $D7x6 - Enhanced sprite colour AND mask (sprite not visible if result = $00)
GS $D7x7 - Enhanced sprite colour OR mask
GS $D7x8-$D7x9 - Enhanced sprite 2x2 linear transform matrix 0,0 (5.11 bits)
GS $D7xA-$D7xB - Enhanced sprite 2x2 linear transform matrix 0,1 (5.11 bits)
GS $D7xC-$D7xD - Enhanced sprite 2x2 linear transform matrix 1,0 (5.11 bits)
GS $D7xE-$D7xF - Enhanced sprite 2x2 linear transform matrix 1,1 (5.11 bits)
C64 $DE01.0 Enable RR-NET emulated clock port ethernet interface
C64 $DE02 RRNET register select register (low)
C64 $DE03 RRNET register select register (low)
C64 $DE06 write to even numbered RR-NET register
C64 $DE06 write to odd numbered RR-NET register
C64 $DE08 RR-NET buffer port (even byte)
C64 $DE09 RR-NET buffer port (even byte)
C64 $DE0C RRNET tx_cmd register (high)
C64 $DE0C RRNET tx_cmd register (low)
C64 $DE0E Set RR-NET TX packet size
C64 $DE0F Set RR-NET TX packet size
GS $FF7Exxx VIC-IV CHARROM write area
GS $FF9x000-$FF9xFFF - Enhanced sprite data buffers (4KB each)
GS $FFBF000 - $FFBFFFF - DEBUG allow writing directly to the bitplane data buffer. Will be removed in production.
GS $FFC00A0 45GS10 slowram wait-states (write-only)
GS $FFDE800 - $FFDEFFF Ethernet RX buffer (read only)
GS $FFDE800 - $FFDEFFF Ethernet TX buffer (write only)
GS $FFF0000-$FFF0FFF - CPU far call stack (512x8 byte entries)
GS $FFF8000 Hypervisor entry point when $D67F is written
GS $FFF8000-$FFFBFFF 16KB Kickstart/hypervisor ROM
GS RR-NET emulation: cs_packet_data high
GS RR-NET emulation: cs_packet_data low