Working Python version for Commodore.
This commit is contained in:
The Dust Council
commit
2a48f52979
51 changed files with 3095 additions and 0 deletions
9
c64view/viewer/__init__.py
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9
c64view/viewer/__init__.py
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"""6502 viewer programs, assembled on demand by assemble.py."""
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from .assemble import ( # noqa: F401
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AssemblerError,
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SOURCES,
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assemble_stub,
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build_viewer_prg,
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have_xa,
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)
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BIN
c64view/viewer/__pycache__/__init__.cpython-313.pyc
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BIN
c64view/viewer/__pycache__/__init__.cpython-313.pyc
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c64view/viewer/__pycache__/assemble.cpython-313.pyc
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c64view/viewer/__pycache__/assemble.cpython-313.pyc
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82
c64view/viewer/assemble.py
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82
c64view/viewer/assemble.py
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"""Assemble the 6502 viewer stubs with `xa` and build self-contained viewer PRGs.
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Each viewer is a small ML stub originating at $0801 (behind a BASIC SYS 2061
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autostart). The picture data is appended after the stub, zero-padded so the
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bitmap lands exactly at $2000, screen RAM at $3F40, etc. The whole thing loads
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in a single pass -- no second disk access -- so it works identically on real
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hardware and in any emulator regardless of device configuration.
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`xa -o` emits raw bytes starting at the origin without the 2-byte CBM load
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address, which we prepend here.
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"""
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from __future__ import annotations
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import os
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import shutil
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import subprocess
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import tempfile
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VIEWER_DIR = os.path.dirname(os.path.abspath(__file__))
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LOAD_ADDR = 0x0801
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DATA_ADDR = 0x2000 # where appended picture data must land
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# mode/viewer key -> source filename
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SOURCES = {
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"hires": "hires.s",
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"multicolor": "multicolor.s",
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"fli": "fli.s",
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"fli_ntsc": "fli_ntsc.s",
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"interlace": "interlace.s",
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}
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_cache: dict[str, bytes] = {}
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class AssemblerError(RuntimeError):
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pass
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def have_xa() -> bool:
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return shutil.which("xa") is not None
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def assemble_stub(viewer_key: str) -> bytes:
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"""Assemble a viewer stub to raw bytes (origin $0801, no load-address prefix)."""
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if viewer_key in _cache:
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return _cache[viewer_key]
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if not have_xa():
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raise AssemblerError(
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"The 'xa' (xa65) assembler was not found on PATH.\n"
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"Install it with: sudo apt install xa65 (Debian/Ubuntu)\n"
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"or build from https://www.floodgap.com/retrotech/xa/")
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src = os.path.join(VIEWER_DIR, SOURCES[viewer_key])
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if not os.path.exists(src):
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raise AssemblerError(f"viewer source missing: {src}")
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with tempfile.TemporaryDirectory() as td:
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out = os.path.join(td, "viewer.bin")
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proc = subprocess.run(["xa", "-o", out, src], capture_output=True, text=True)
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if proc.returncode != 0:
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raise AssemblerError(f"xa failed for {src}:\n{proc.stdout}{proc.stderr}")
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with open(out, "rb") as f:
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raw = f.read()
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_cache[viewer_key] = raw
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return raw
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def build_viewer_prg(viewer_key: str, data: bytes, data_addr: int = DATA_ADDR) -> bytes:
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"""Combine the assembled stub + padding + picture ``data`` into one PRG.
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``data`` is the block that must reside from ``data_addr`` upward (bitmap,
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screen, colour RAM, background, ...).
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"""
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stub = assemble_stub(viewer_key)
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pad_len = (data_addr - LOAD_ADDR) - len(stub)
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if pad_len < 0:
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raise AssemblerError(
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f"viewer stub {viewer_key} is {len(stub)} bytes, exceeds the "
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f"{data_addr - LOAD_ADDR} bytes available before ${data_addr:04x}")
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payload = stub + bytes(pad_len) + bytes(data)
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return bytes([LOAD_ADDR & 0xFF, (LOAD_ADDR >> 8) & 0xFF]) + payload
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151
c64view/viewer/fli.s
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151
c64view/viewer/fli.s
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@ -0,0 +1,151 @@
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; c64view -- FLI multicolor viewer (self-contained)
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;
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; Re-points the VIC video matrix ($D018) and forces a badline ($D011 yscroll)
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; on every visible raster line via a cycle-timed loop, giving per-line colour.
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;
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; Memory layout of appended data (loads from $4000):
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; $4000+L*$400 screen RAM for line L (L=0..7), 1000 bytes each
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; $6000 bitmap 8000 (offset $2000 in VIC bank 1)
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; $8000 colour RAM 1000 (copied to $D800)
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; $83E8 background 1
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;
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; assembled by viewer/assemble.py via xa
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; BASIC autostart, SYS 2061
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* = $0801
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.word basicend
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.word 10
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.byte $9e
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.byte "2061"
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.byte 0
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basicend:
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.word 0 ; ML begins at $080D
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start:
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sei
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; copy colour RAM $8000 -> $D800 (1024 bytes)
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ldx #0
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ccopy:
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lda $8000,x
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sta $d800,x
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lda $8100,x
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sta $d900,x
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lda $8200,x
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sta $da00,x
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lda $8300,x
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sta $db00,x
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inx
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bne ccopy
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; build per-line tables. d018tab = ((line AND 7) << 4) OR $08
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; d011tab = $38 OR (line AND 7) = BMM+DEN+RSEL plus yscroll
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ldx #0
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btab:
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txa
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and #$07
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asl
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asl
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asl
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asl
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ora #$08
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sta d018tab,x
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; yscroll must equal (raster AND 7) to force a badline; the first
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; displayed raster is 51, so line x maps to raster 51+x.
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txa
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clc
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adc #$03
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and #$07
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ora #$38
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sta d011tab,x
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inx
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bne btab
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; VIC bank 1 ($4000-$7FFF)
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lda $dd00
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and #$fc
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ora #$02
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sta $dd00
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lda $83e8
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sta $d021 ; background
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lda #$00
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sta $d020 ; border black
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lda #$d8
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sta $d016 ; multicolor on
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; raster IRQ setup
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lda #<irq1
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sta $0314
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lda #>irq1
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sta $0315
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lda #$7f
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sta $dc0d ; disable CIA timer IRQs
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sta $dd0d
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lda $dc0d
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lda $dd0d
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lda #$01
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sta $d01a ; enable raster IRQ
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lda #$30
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sta $d012 ; line 48
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lda $d011
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and #$7f
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sta $d011
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asl $d019 ; ack
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cli
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hang:
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jmp hang
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; first IRQ, arrives with jitter on line 48, sets up the stabilised one
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irq1:
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lda #<irq2
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sta $0314
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lda #>irq2
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sta $0315
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inc $d012 ; fire again next line (49)
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asl $d019 ; ack
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tsx
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cli
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; burn the rest of the line so irq2 fires inside this NOP slide
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.dsb 40,$ea ; 40 NOPs
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; stabilised IRQ on line 49, runs the FLI loop
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irq2:
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txs ; restore sp from irq1
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; cancel the remaining 0/1-cycle jitter: read the raster twice; the
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; branch is 2 or 3 cycles depending on alignment, normalising entry.
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lda $d012
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cmp $d012
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beq jl
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jl:
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; fixed delay so the first store lands before the c-access window
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ldx #$0d
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d0: dex
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bne d0
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nop
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nop
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ldx #$00
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fliloop:
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lda d011tab,x ; force badline (yscroll = line&7)
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sta $d011
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lda d018tab,x ; point video matrix at screen[line]
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sta $d018
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inx
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cpx #200
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bne fliloop
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; bottom border: leave bitmap on but stop forcing badlines
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lda #<irq1
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sta $0314
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lda #>irq1
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sta $0315
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lda #$30
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sta $d012
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asl $d019
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jmp $ea81 ; restore regs + RTI
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d018tab:
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.dsb 256,0
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d011tab:
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.dsb 256,0
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155
c64view/viewer/fli_ntsc.s
Normal file
155
c64view/viewer/fli_ntsc.s
Normal file
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@ -0,0 +1,155 @@
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; c64view -- FLI multicolor viewer, NTSC timing (self-contained)
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;
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; Same as fli.s but the inner loop is one NOP (2 cycles) longer so it self-syncs
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; to the NTSC 65-cycle raster line (25 free CPU cycles per badline) vs PAL's 63.
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;
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; Re-points the VIC video matrix ($D018) and forces a badline ($D011 yscroll)
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; on every visible raster line via a cycle-timed loop, giving per-line colour.
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;
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; Memory layout of appended data (loads from $4000):
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; $4000+L*$400 screen RAM for line L (L=0..7), 1000 bytes each
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; $6000 bitmap 8000 (offset $2000 in VIC bank 1)
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; $8000 colour RAM 1000 (copied to $D800)
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; $83E8 background 1
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;
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; assembled by viewer/assemble.py via xa
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; BASIC autostart, SYS 2061
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* = $0801
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.word basicend
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.word 10
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.byte $9e
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.byte "2061"
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.byte 0
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basicend:
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.word 0 ; ML begins at $080D
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start:
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sei
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; copy colour RAM $8000 -> $D800 (1024 bytes)
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ldx #0
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ccopy:
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lda $8000,x
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sta $d800,x
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lda $8100,x
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sta $d900,x
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lda $8200,x
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sta $da00,x
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lda $8300,x
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sta $db00,x
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inx
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bne ccopy
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; build per-line tables. d018tab = ((line AND 7) << 4) OR $08
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; d011tab = $38 OR (line AND 7) = BMM+DEN+RSEL plus yscroll
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ldx #0
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btab:
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txa
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and #$07
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asl
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asl
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asl
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asl
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ora #$08
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sta d018tab,x
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; yscroll must equal (raster AND 7) to force a badline; the first
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; displayed raster is 51, so line x maps to raster 51+x.
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txa
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clc
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adc #$03
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and #$07
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ora #$38
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sta d011tab,x
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inx
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bne btab
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; VIC bank 1 ($4000-$7FFF)
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lda $dd00
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and #$fc
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ora #$02
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sta $dd00
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lda $83e8
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sta $d021 ; background
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lda #$00
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sta $d020 ; border black
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lda #$d8
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sta $d016 ; multicolor on
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; raster IRQ setup
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lda #<irq1
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sta $0314
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lda #>irq1
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sta $0315
|
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lda #$7f
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sta $dc0d ; disable CIA timer IRQs
|
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sta $dd0d
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lda $dc0d
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lda $dd0d
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lda #$01
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sta $d01a ; enable raster IRQ
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lda #$30
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sta $d012 ; line 48
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lda $d011
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and #$7f
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sta $d011
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asl $d019 ; ack
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cli
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hang:
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jmp hang
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||||
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; first IRQ, arrives with jitter on line 48, sets up the stabilised one
|
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irq1:
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lda #<irq2
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sta $0314
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lda #>irq2
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sta $0315
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inc $d012 ; fire again next line (49)
|
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asl $d019 ; ack
|
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tsx
|
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cli
|
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; burn the rest of the line so irq2 fires inside this NOP slide
|
||||
.dsb 40,$ea ; 40 NOPs
|
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|
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; stabilised IRQ on line 49, runs the FLI loop
|
||||
irq2:
|
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txs ; restore sp from irq1
|
||||
; cancel the remaining 0/1-cycle jitter: read the raster twice; the
|
||||
; branch is 2 or 3 cycles depending on alignment, normalising entry.
|
||||
lda $d012
|
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cmp $d012
|
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beq jl
|
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jl:
|
||||
; fixed delay so the first store lands before the c-access window
|
||||
ldx #$0d
|
||||
d0: dex
|
||||
bne d0
|
||||
nop
|
||||
nop
|
||||
|
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ldx #$00
|
||||
fliloop:
|
||||
lda d011tab,x ; force badline (yscroll = line&7)
|
||||
sta $d011
|
||||
lda d018tab,x ; point video matrix at screen[line]
|
||||
sta $d018
|
||||
nop ; NTSC extra 2 cycles for 65 cycle line
|
||||
inx
|
||||
cpx #200
|
||||
bne fliloop
|
||||
|
||||
; bottom border: leave bitmap on but stop forcing badlines
|
||||
lda #<irq1
|
||||
sta $0314
|
||||
lda #>irq1
|
||||
sta $0315
|
||||
lda #$30
|
||||
sta $d012
|
||||
asl $d019
|
||||
jmp $ea81 ; restore regs + RTI
|
||||
|
||||
d018tab:
|
||||
.dsb 256,0
|
||||
d011tab:
|
||||
.dsb 256,0
|
||||
80
c64view/viewer/hires.s
Normal file
80
c64view/viewer/hires.s
Normal file
|
|
@ -0,0 +1,80 @@
|
|||
; c64view -- hires bitmap viewer (self-contained)
|
||||
;
|
||||
; The picture data is appended to this program by the exporter and loads in one
|
||||
; pass. Fixed memory layout after load:
|
||||
; $0801 this program (BASIC stub + ML, padded up to $2000)
|
||||
; $2000 bitmap 8000 (VIC reads here directly)
|
||||
; $3F40 screen 1000 (copied to $0400)
|
||||
;
|
||||
; assembled by viewer/assemble.py via xa
|
||||
|
||||
; BASIC autostart, SYS 2061
|
||||
* = $0801
|
||||
.word basicend
|
||||
.word 10
|
||||
.byte $9e
|
||||
.byte "2061"
|
||||
.byte 0
|
||||
basicend:
|
||||
.word 0 ; ML begins at $080D
|
||||
|
||||
SRC = $fb
|
||||
DST = $fd
|
||||
|
||||
start:
|
||||
lda #$0b
|
||||
sta $d011 ; blank during setup
|
||||
|
||||
; copy screen RAM $3F40 -> $0400
|
||||
lda #$40
|
||||
sta SRC
|
||||
lda #$3f
|
||||
sta SRC+1
|
||||
lda #$00
|
||||
sta DST
|
||||
lda #$04
|
||||
sta DST+1
|
||||
jsr copy1024
|
||||
|
||||
lda $dd00
|
||||
ora #$03
|
||||
sta $dd00 ; VIC bank 0
|
||||
lda #$00
|
||||
sta $d020
|
||||
lda #$18
|
||||
sta $d018 ; screen $0400, bitmap $2000
|
||||
lda #$c8
|
||||
sta $d016 ; hires (multicolor off)
|
||||
lda #$3b
|
||||
sta $d011 ; bitmap mode, display on
|
||||
lda #$ff
|
||||
sta $cc
|
||||
|
||||
waitkey:
|
||||
jsr $ffe4
|
||||
beq waitkey
|
||||
|
||||
lda #$1b
|
||||
sta $d011
|
||||
lda #$c8
|
||||
sta $d016
|
||||
lda #$15
|
||||
sta $d018
|
||||
lda #$00
|
||||
sta $cc
|
||||
jsr $e544
|
||||
rts
|
||||
|
||||
copy1024:
|
||||
ldx #4
|
||||
ldy #0
|
||||
cploop:
|
||||
lda (SRC),y
|
||||
sta (DST),y
|
||||
iny
|
||||
bne cploop
|
||||
inc SRC+1
|
||||
inc DST+1
|
||||
dex
|
||||
bne cploop
|
||||
rts
|
||||
139
c64view/viewer/interlace.s
Normal file
139
c64view/viewer/interlace.s
Normal file
|
|
@ -0,0 +1,139 @@
|
|||
; c64view -- multicolor interlace viewer (self-contained)
|
||||
;
|
||||
; Shows two multicolor frames on alternating fields by flipping the VIC bank in a
|
||||
; once-per-frame raster IRQ (no cycle-exact timing needed, so it is robust).
|
||||
; Frame A lives in bank 0 (bitmap $2000, screen $0400); frame B in bank 1 (bitmap
|
||||
; $6000, screen $4400). Both use $D018=$18; only the $DD00 bank bit toggles.
|
||||
;
|
||||
; Memory layout of appended data (loads from $2000):
|
||||
; $2000 bitmap A 8000
|
||||
; $3F40 screen A 1000 (copied to $0400)
|
||||
; $4400 screen B 1000 (in place, bank 1 video matrix)
|
||||
; $6000 bitmap B 8000
|
||||
; $8000 colour RAM 1000 (copied to $D800)
|
||||
; $83E8 background 1
|
||||
;
|
||||
; assembled by viewer/assemble.py via xa
|
||||
|
||||
; BASIC autostart, SYS 2061
|
||||
* = $0801
|
||||
.word basicend
|
||||
.word 10
|
||||
.byte $9e
|
||||
.byte "2061"
|
||||
.byte 0
|
||||
basicend:
|
||||
.word 0
|
||||
|
||||
SRC = $fb
|
||||
DST = $fd
|
||||
|
||||
start:
|
||||
sei
|
||||
|
||||
; screen A $3F40 -> $0400
|
||||
lda #$40
|
||||
sta SRC
|
||||
lda #$3f
|
||||
sta SRC+1
|
||||
lda #$00
|
||||
sta DST
|
||||
lda #$04
|
||||
sta DST+1
|
||||
jsr copy1024
|
||||
|
||||
; colour RAM $8000 -> $D800
|
||||
lda #$00
|
||||
sta SRC
|
||||
lda #$80
|
||||
sta SRC+1
|
||||
lda #$00
|
||||
sta DST
|
||||
lda #$d8
|
||||
sta DST+1
|
||||
jsr copy1024
|
||||
|
||||
lda $83e8
|
||||
sta $d021 ; background
|
||||
lda #$00
|
||||
sta $d020 ; border black
|
||||
lda $dd00
|
||||
and #$fc
|
||||
ora #$03
|
||||
sta $dd00 ; start on VIC bank 0 (frame A)
|
||||
lda #$18
|
||||
sta $d018 ; screen $x400, bitmap $x000+$2000
|
||||
lda #$d8
|
||||
sta $d016 ; multicolor on
|
||||
lda #$3b
|
||||
sta $d011 ; bitmap mode, display on
|
||||
|
||||
; frame-flip raster IRQ near the bottom border
|
||||
lda #<irq
|
||||
sta $0314
|
||||
lda #>irq
|
||||
sta $0315
|
||||
lda #$7f
|
||||
sta $dc0d
|
||||
sta $dd0d
|
||||
lda $dc0d
|
||||
lda $dd0d
|
||||
lda #$01
|
||||
sta $d01a
|
||||
lda #$fa
|
||||
sta $d012 ; line 250
|
||||
lda $d011
|
||||
and #$7f
|
||||
sta $d011
|
||||
asl $d019
|
||||
cli
|
||||
|
||||
waitkey:
|
||||
jsr $ffe4 ; GETIN (scanned via our IRQ -> $ea31)
|
||||
beq waitkey
|
||||
|
||||
; restore text mode + KERNAL IRQ
|
||||
sei
|
||||
lda #$00
|
||||
sta $d01a ; disable raster IRQ
|
||||
lda #$81
|
||||
sta $dc0d ; re-enable CIA timer IRQ
|
||||
lda #$31
|
||||
sta $0314
|
||||
lda #$ea
|
||||
sta $0315
|
||||
lda #$1b
|
||||
sta $d011
|
||||
lda #$c8
|
||||
sta $d016
|
||||
lda #$15
|
||||
sta $d018
|
||||
lda $dd00
|
||||
ora #$03
|
||||
sta $dd00
|
||||
asl $d019
|
||||
cli
|
||||
jsr $e544 ; clear screen
|
||||
rts
|
||||
|
||||
; once per frame, flip bank 0 <-> bank 1, then let the KERNAL IRQ finish
|
||||
irq:
|
||||
lda $dd00
|
||||
eor #$01
|
||||
sta $dd00
|
||||
asl $d019 ; ack raster IRQ
|
||||
jmp $ea31 ; KERNAL housekeeping (keyboard) + RTI
|
||||
|
||||
copy1024:
|
||||
ldx #4
|
||||
ldy #0
|
||||
cploop:
|
||||
lda (SRC),y
|
||||
sta (DST),y
|
||||
iny
|
||||
bne cploop
|
||||
inc SRC+1
|
||||
inc DST+1
|
||||
dex
|
||||
bne cploop
|
||||
rts
|
||||
98
c64view/viewer/multicolor.s
Normal file
98
c64view/viewer/multicolor.s
Normal file
|
|
@ -0,0 +1,98 @@
|
|||
; c64view -- multicolor (Koala) bitmap viewer (self-contained)
|
||||
;
|
||||
; The picture data is appended to this program by the exporter and loads in one
|
||||
; pass, so no second disk access is needed. Fixed memory layout after load:
|
||||
; $0801 this program (BASIC stub + ML, padded up to $2000)
|
||||
; $2000 bitmap 8000 (VIC reads here directly)
|
||||
; $3F40 screen 1000 (copied to $0400)
|
||||
; $4328 colram 1000 (copied to $D800)
|
||||
; $4710 background 1
|
||||
;
|
||||
; assembled by viewer/assemble.py via xa
|
||||
|
||||
; BASIC autostart, SYS 2061
|
||||
* = $0801
|
||||
.word basicend
|
||||
.word 10
|
||||
.byte $9e
|
||||
.byte "2061"
|
||||
.byte 0
|
||||
basicend:
|
||||
.word 0 ; ML begins at $080D
|
||||
|
||||
SRC = $fb
|
||||
DST = $fd
|
||||
|
||||
start:
|
||||
lda #$0b
|
||||
sta $d011 ; blank screen during setup
|
||||
|
||||
; copy screen RAM $3F40 -> $0400
|
||||
lda #$40
|
||||
sta SRC
|
||||
lda #$3f
|
||||
sta SRC+1
|
||||
lda #$00
|
||||
sta DST
|
||||
lda #$04
|
||||
sta DST+1
|
||||
jsr copy1024
|
||||
|
||||
; copy colour RAM $4328 -> $D800
|
||||
lda #$28
|
||||
sta SRC
|
||||
lda #$43
|
||||
sta SRC+1
|
||||
lda #$00
|
||||
sta DST
|
||||
lda #$d8
|
||||
sta DST+1
|
||||
jsr copy1024
|
||||
|
||||
; program the VIC-II
|
||||
lda $dd00
|
||||
ora #$03
|
||||
sta $dd00 ; VIC bank 0 ($0000-$3FFF)
|
||||
lda $4710
|
||||
sta $d021 ; background colour
|
||||
lda #$00
|
||||
sta $d020 ; border black
|
||||
lda #$18
|
||||
sta $d018 ; screen $0400, bitmap $2000
|
||||
lda #$d8
|
||||
sta $d016 ; multicolor mode on
|
||||
lda #$3b
|
||||
sta $d011 ; bitmap mode, display on
|
||||
lda #$ff
|
||||
sta $cc ; disable cursor blink
|
||||
|
||||
waitkey:
|
||||
jsr $ffe4 ; GETIN
|
||||
beq waitkey
|
||||
|
||||
; restore text mode and return to BASIC
|
||||
lda #$1b
|
||||
sta $d011
|
||||
lda #$c8
|
||||
sta $d016
|
||||
lda #$15
|
||||
sta $d018
|
||||
lda #$00
|
||||
sta $cc
|
||||
jsr $e544 ; clear screen
|
||||
rts
|
||||
|
||||
; copy 1024 bytes from (SRC) to (DST)
|
||||
copy1024:
|
||||
ldx #4
|
||||
ldy #0
|
||||
cploop:
|
||||
lda (SRC),y
|
||||
sta (DST),y
|
||||
iny
|
||||
bne cploop
|
||||
inc SRC+1
|
||||
inc DST+1
|
||||
dex
|
||||
bne cploop
|
||||
rts
|
||||
Loading…
Add table
Add a link
Reference in a new issue