plus4emu

plus4emu is an open source, portable emulator of the Commodore 264 family of computers (C16, C116, and Plus/4), written in C++, and supporting Windows and POSIX platforms (32 bit Windows, 32 and 64 bit Linux, and MacOS X have been tested). It implements accurate, high quality hardware emulation, however, the system requirements are higher than that of most other emulators.

Features

Usage

News

plus4emu 1.2.5 has been released (9 Dec 2007)

implemented Lua scripting in the debugger; this makes it possible to write complex rules for breakpoints, but can have other uses as well, since the script can read and write memory and CPU registers, in addition to having access to the standard Lua library functions
changed the debugger window layout so that there is a larger window with only two tabs
the disassembly view in the debugger now allows for paging backward, and the disassembly and memory dump displays can also be scrolled with the mouse wheel
made the serial bus delay for the 1541 high timing accuracy mode adjustable; while the default setting works with all the disk turbos tested so far, this option may be useful for debugging purposes
when using audio files as tape images, the signal read or written can optionally be inverted for compatibility with other software
the enabling of 6551 ACIA emulation is now configurable, rather than being fixed to machine configurations with 64K or more RAM
SID emulation and floppy drives with no disk image attached can be disabled from the GUI menu to reduce CPU usage; previously, these automatically enabled features could only be turned off by a forced or hard reset
added new GUI menu items for resetting floppy drives
new command line option (-tape) for loading tape images on startup; it has also been made possible to automatically load a file with .prg, .p00, .d64, .d81, or .tap extension by using the file name as a single command line argument
minor bug fixes and optimizations

plus4emu 1.2.4 release (22 Nov 2007)

implemented the ACIA 6551 registers at $FD00-$FD0F, which are automatically enabled for configurations with 64K or more RAM; this is not complete yet, but the basic functionality works
video recording can also be done in RLE8 format now, which allows smaller file sizes than uncompressed YV12, at the expense of some TV emulation effects not being captured
added new command line option for selecting the GUI style and colors
various minor improvements and bug fixes

plus4emu 1.2.3 has been released (1 Oct 2007)

video and sound output can be recorded to AVI files
more accurate colors in NTSC mode
TED sound emulation improvements
added hue shift to the display configuration options
minor optimizations in serial floppy drive and printer emulation
the drive head position is now also shown on the LED display when it is changing
a few bug fixes

plus4emu 1.2.2 is released (6 Sep 2007)

implemented Digi-Blaster emulation
added limited support for error information in D64 files
new option for setting SID model (6581 or 8580) to be emulated
P00 format files can be loaded
emulation speed percentage is now displayed on the title bar; it is also possible to set half, double, etc. speed in the menu
the head position (track, side, and sector) of all floppy drives can be displayed in a window

plus4emu 1.2.1 release (9 Aug 2007)

TED emulation improvements; also fixed a bug introduced in version 1.1.1
the frame rate in full speed mode is now limited to a maximum of 50 Hz to improve performance
minor bug fixes

plus4emu 1.2.0 has been released (26 Jul 2007)

many improvements in the TV emulation; to enable all the new features, use OpenGL mode and set the display quality to 3 (requires OpenGL 2.0 or newer and shader support)
added a tedmon-like monitor to the debugger; it supports all the commands, including assemble, but there are also some improvements and additional features (use ? to print the list of commands, or ? N for help on command N)
it is now possible to set breakpoints on TED video positions in the debugger
trace command in the monitor for logging CPU instructions to a text file; when debugging the main CPU, the TED video position at the first cycle of each opcode is also logged
light pen emulation
hardware level 1526/MPS-802 printer emulation
the file I/O ROM module now also includes a tape turbo; to enable it, set $0647 to $17, $27, $37, or $47 to select speed (from slowest to fastest), and use device 7 when saving
tape playback and recording can be sent to the sound output
the RAM startup pattern has been made configurable
minor TED emulation improvements
various bug fixes

plus4emu 1.2.0 beta release (16 Jul 2007)

plus4emu 1.1.3 has been released (14 Jun 2007)

fixed bug in Hannes memory expansion emulation
improved 6523 emulation in 1551 floppy drives
minor bug fixes

New release (1.1.2) with some bug fixes (10 Jun 2007)

fixed a bug that caused the tape input signal to get stuck at high level sometimes even after stopping or closing the tape
optimizations in 1541 high timing accuracy mode
adjusted reSID filter for the different clock frequency used in Plus/4

plus4emu 1.1.1 is released (06 Jun 2007)

added new 1541 timing code that fixes some programs that previously did not load, at the expense of higher CPU usage; it is enabled by default, and can be turned on/off in the floppy configuration dialog
more accurate emulation of television vertical synchronization
MacOS X build fixes; also added patch for FLTK 1.1.7 which fixes the check callback on OS X
improvements and fixes in TED video shift register emulation
fixed CPU I/O port data direction register ($0000)
the ROM package now includes the 1541 DOS, rather than the 1541-II; however, it is still possible to use the 1541-II by loading dos15412.rom to ROM segment 10 in the machine configuration
minor optimizations

plus4emu 1.1.0 has been released (15 May 2007)

implemented 1551 drive emulation
added floppy drive LED display to the GUI (1541 is red, 1551 is green, and 1581 is yellow)
the debugger now allows for debugging floppy drives; the drives are also mapped to the physical address range $180000-$1BFFFF
fixed 1541 disk change detection
keyboard map can be configured with the GUI
external game devices like joysticks and gamepads are supported, and can be assigned in the keyboard map like normal keys
the 'step over' button in the debugger now also skips branch instructions
invalid opcodes that normally jam the CPU can be used as breakpoints (with the priority assumed to be 3) that open the debugger, and the execution of the program can continue as if there was a NOP instruction
added new command line options for loading disk image, snapshot, and demo files on start-up; on Windows, D64 and D81 files are also optionally associated with the emulator
it is now possible to use WAV, AIFF, and other sound file formats as tape images; these files can be read and written, however, new files are created in plus4emu format
blank video output is generated when the TED is disabled by setting bit 5 of $FF07
reduced horizontal texture resolution to 384 in OpenGL mode when the quality is set to 0, for improved performance
minor GUI improvements and fixes