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2.2 / 23-01-2023

Z64K

Accuracy

Performance

Features

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Z64K runs on any platform with an updated Java Runtime Environment installed. 

It runs multiple computing devices such as Atari 2600 (cycle-accurate 6507 & pixel-accurate TIA emulation), Commodore 64 (cycle-exact 6510 including all undocumented instructions, CIA 6522/6522a emulation (cycle-exact SID 6581 emulation based on reSID, etc.), Commodore 128 (All features of C64 with most VDC features), Z80 processor emulated though not 100% cycle accurate, VIC 20 (cycle-accurate), Disk drive support (CBM 1541, CBM 1571, CBM 1581) and much more.

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RequirementJava Runtime Environment 7+

Note: JAVA 9 and 10: use the â€“Dsun.java2d.uiScale=1.0 option, if the screen does not render nicely on your setup. 

See bug for details..

Most Recent Changes

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  • Fixed bug that prevented saving of second side of d71 disk images.

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  • Z80 stack pointer set on 0xffff on reset. Fixes a few issues with programs that don't explicitly configure the stack point on startup

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  • Fix bug with Testbench not starting if it hasn't been previouslyconfigured

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  • Minor updates to improve catching of filechooser race conditions that very rarely causes null value error that crashes emulator.

  • Machine monitor peeks IO range for C128 when mapped in.

  • Update MMU to behave like majority of tested C128's where zeropage and stack are both set to the same page.  All mmu tests in VICE test repository pass.

  • Allow mapping in of C128 kernal while in Z80 mode.

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  • Virtual FS scratch command will add .del extension to "deleted" file. When saving new file with same filename as "deleted" file, the "deleted" file will be removed from the host file system.

  • Show read only flag if set when displaying  directory in Virtual FS.

  • Prevent saving of files with invalid host system filename when using Virtual FS.

  • Allow wildcard (* and ?) filters when loading Virtual FS directory.

  • Virtual FS scratch command simulated but does not currently delete any files from host file system.

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  • Select correct drive when loading disk image if Virtual FS is currently selected

  • Disk viewer can be scrolled by mouse wheel.

  • Improved accuracy of clickable disk viewer when scrolled

  • Fix bug when loading file via double clicking disk viewer for device 10 and 11.

  • Double clicking DIR file types in disk viewer will open that directory.

  • Show files in Disk preview for Virtual FS.

  • Adjust calculated file block size s for virtual FS

  • Fix minor bug where Virtual FS CD doesn't work immediately after reset

  • Allow saving of files with Virtual FS.

  • Virtual FS load"*",8 will load the last loaded program.  If no programs have previously been loaded, the first program will be loaded.

  • Fix bug with Virtual FS where JiffyDOS protocol could be incorrectly triggered when byte $61 is received directly after a talk request

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  • Current folder selector for Virtual FS available in drive settings.

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  • Fixed wildcard loading of firstfile with Virtual VS

  • Fixed bug that prevented JiffyDos command @$ from working with Virtual FS

  • Improved Virtual FS JiffyDOS timing.

  • Implement Virtual FS UI command. C128 "warm resets" drive message on error channel.

  • Flash LED when error occurs with Virtual FS

  • Improved reliability ofVirtual FS JiffDos support.

  • Ordered Virtual FS display of subdirectories and files.

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  • Update status of Virtual FS in disk UI

  • Improved Virtual FS error handling

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  • Improved C128 Virtual FS device support

  • Improved Virtual FS device JiffyDOS support

  • load programs with .prg extension without needing to include the .prg in the load command

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  • New Virtual FS device available under drive type settings - Experimental and still a work in progress. Location set to prg path inpaths setting.

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  • Fixed bug that caused emulator to crash on exit with older versions of saved config

  • Include SID Analyzer in version 2 of Z64K.
    F1 = Toggle voice 1 ON/OFF
    F2 = Toggle voice 2 ON/OFF
    F3 = Toggle voice 3 ON/OFF
    F4 = Toggle voice 4 (volume samples) ON/OFF
    F5 = Display waveform
    F6 = Display envelope
    F7 = Display oscillator
    F8 = Display combined
    F9 = Pause (press F5-F8 to un-pause)
    F11 = speed down
    F12 = speed up

  • Decommission version 1 of Z64K.

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  • Improved emulation of single pixel mode when char total horizontal less than 8 pixels .

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  • Implement some odd behaviors of VDC in single pixel mode when char total horizontal less than 8 pixels.

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  • Mouse can be captured using eitherVDC or VIC screen

  • Double click of mouse toggles full screen

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  • Fixed bug with c1541 and c1571 snapshot component that wasn't saving VIA state correctly.

  • Fixed bug with C128 snapshots that prevented VDC and 2nd 64K RAM bank from saving.

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  • U2+/U64 "enhanced" g71 read support.

  • Save current ROM configuration on exit.

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  • add ASCII/DIN option for c128 chargen in ROM settings.

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  • Use correct part of c128 chargen ROMin C128 mode.

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  • Bug fix with size of each stored track in g71 header to use LO/HI

  • Assembler updates to add support for equ, dc and ds keywords

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  • Minor fixes to saving and loading of g71 images

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  • Improved IMD disk image support

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  • Loading of 5.25 Imagedisk (.imd) image support.

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  • Fixed bug that wouldn't allow all MFM sectors to load from g71 images

  • Minor update to g71 format to keep header as GCR-1571 for images with MFM tracks

  • Included support to save g64 images

  • Included support to load and save g71 images (includes saving of MFM tracks if they exist). note: preview window for some g71 images might not work.

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  • Fixed bug when load g64 images with half tracks

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  • remove debugging output

  • Minor improvements forsupport of g64 images

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  • Improved diskSYNC detection

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  • update from today's previous version:- 1571 MFM uses the same disk surface as GCR.

  • Major update to 5.25 disk surface. 
    Improved custom speed zone handling. All VICE test repository RPM tests pass.
    1571 burst MFM support. All R/W tests of the 1571 system version  test 1.2.1 including MFM format and mfm burst write/read/compare pass.

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  • Improve VIA shift register behavior.  All VICE test repository shift register tests pass

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  • Fix VIA handshaking of CB2.  Majority of VICE VIC 20 VIA SR tests pass.

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  • VICIIModel command line option. Possible values 6569, 8565, 6567, 8562, or 6567r56a.

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  • Fixed update of Testbench directory.  Can use testbench straight away once valid testbench directory is configured.

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  • Add drive8type, drive9type, drive10type, and drive11type command line options.  Possible values are none,1541, 1571, or 1581. e.g Z64K.jar c64 -drive8type 1571

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  • Updated Userport DAC to have four 8 bit D/A Convertors. ModPlay DigiMAX stereo - 8 bit  userport DAC driver is now supported.

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  • Increase timeout before hard reset when autoloading file off disk via command line options.  C128 can start programs off disk in c64 mode now.

  • Autostart of program of mounted disk using wildcard via command line options loads first PRG file off disk

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  • Fix z80 behavior using bank 2 without extended memory

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  • Updates to c128 mmu.  mmuswap-08 and mmuswap-16 pass.  All test results match real hardware.

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  • Use correct block for zero page and stack when RAM backs 2 & 3 are enabled.  Fixes PIA globe test

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  • Update to c128 mmu swap of zero page to stack and vice versa. All test results match real hardware, as per link

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  • Allow autoload of file on disk via command line.  

  • Append disk source filename with colon and file to be automatically loaded. eg java -jar Z64K.jar c64-8 G:\old_school\C64\disks\geos-plain.d64:boot

  • 128, 256, 512, 1024, 2024, and 4096 selectable GEORAM sizes.

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  • Include updating Z80 registers HL in machine monitor

  • C128 writes to dxxx RAM in Z80 mode for bank 0

  • Enable beeper by default for ZX Spectrum

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  • Fixed bug that prevented path and rom locations being reloaded from saved configuration.

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  • opengl disabled by default.  Should only be enabled if UI issues occur on newer graphic cards.  Option to enable is available in General Global Settings.  Emulator needs to be restarted before effects are applied.

  • new command line option -safemode.  Disables opengl in config if unable to access settings to unselect the opengl option, All other command line options are ignored in safemode  eg. java -jar Z64K.jar -safemode

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  • Use opengl for hardware acceleration. Fixes glitches in UI without need for Dsun.java2d.d3d=false as a VM option at startup. Improves screen refresh.

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  • Swiftlink cartridge supports Turbo232 speeds

  • Cartridges that don't use IO1 and/or IO2 can be connected at the same time as other expansion devices.

  • UI changes to cartridge settings.

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  • Disable audio master gain adjustment for systems that don't support it.

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  • Updates to Swiftlink cartridge to support retroterm

  • Included buffer free progress bar in settings for internal userport modem.

  • Improved some rs232 badly formed address error handling.

  • Echo, quiet and verbose toggle button available in settings for userport internal modem

  • Set echo default to false.  Prevents UP9600 driver in Striketerm being locked if modem on when driver selected

  • Detect when client disconnects.

  • Minor improvements to Hayes Modem command mode behavior.

  • Internal modem echo on and quiet off by default.  Echo only in command mode.

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  • Disable audio master gain adjustment for systems that don't support it.

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  • Updates to Swiftlink cartridge to support retroterm

  • Included buffer free progress bar in settings for internal userport modem.

  • Improved some rs232 badly formed address error handling.

  • Echo, quiet and verbose toggle button available in settings for userport internal modem

  • Set echo default to false.  Prevents UP9600 driver in Striketerm being locked if modem on when driver selected

  • Detect when client disconnects.

  • Minor improvements to Hayes Modem command mode behavior.

  • Internal modem echo on and quiet off by default.  Echo only in command mode.

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  • Improved timing of userport rs232 receiving of data.  Streaming of audio using retroterm 0.13 plays audio stream at correct speed and no longer causes modem buffer to overflow when playing long streams.

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  • Increase internal modem buffer size

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  • Minor Improvements to Machine Monitor next command behaviour.

  • Added Machine Monitor next (n) command.  Single steps instruction but treats subroutines as a single instruction.  Note to self: Must find some decent icons for the single stepping icons. :)

  • Fixed debugging with monitor for C128 Z80 cpu memory locations $1800-$3fff

  • REU retains memory after reset

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  • Allow Userport modem to send and receive data at same time

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  • Added 57600 baud rate option for userport rs232 to support Retroterm V0.13

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  • Fixed reset bug that wasn't clearing Z80 HALT state when interrupts were disabled.

  • Improvements with Z80 HALT timing

  • More improvements to ZX spectrum snow effect

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  • Setting of Z80 registers using machine monitor is now functional

  • Setting of Z80/6502 registers with machine monitoruses current radix

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  • Default internal modem with echo off, verbose on, and quiet on.

  • Improved internal modem Hayes command set.

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  • Fixed broken fast 1581 serial caused by recent changes to support UP9600

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  • Included a default keyboard mapping for German keyboards thanks to Tokra . Disclaimer: not thoroughly tested but is much better than the default English mapping when using a German Keyboard. :)

  • Fixed restore key for VIC20.

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  • VIC 20 uses mike-pal.vpl as default

  • Some minor fixes with timing of VIC interlace signal

  • Userport rs232 modem synchronisation greatly improved.  Data transfers much more reliable with UP9600 and standard userport drivers.

  • Minor adjustment to value read for VIC $9004 register when in NTSC mode depending on cycle

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  • Added UP9600 rs232 modem support.

  • Fixed bug with automatic loading of SDR value into CIA shift register when loaded at same time as final bit of previous SDRshifted out.

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  • Improvements to Userport RS232.  Huge improvement with sending valid data!

  • Fixed ZX spectrum settings title

  • Allow ZX spectrum to be default application on startup

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  • Fixed bug with command line option -limitcycles that caused it not to trigger with TestBench scripts.

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  • Minor change to latching behaviour to trigger on correct edge as set in ACR. Drive sends pulse from byte ready signalto trigger latching.

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  • Update to VIA port latching.  Fixes VICE bug#582 and Freespin still works!

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  • Fixed bug with VIA latching not clearing when CA1 interrupt is cleared.  Freespin demo doesn't crash anymore. :)

  • Added undocumented drive machine monitor commands motor and track
    motor [on:off] - turn motor on/off , without arguments prints status of drive motor
    track [in:out] - move rw head in/out 1 half track, without arguments prints current track

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  • Enabled Internal Palette selector available in settings.

  • Updated default VDC palette to c128-vdc-deekay.vpl as suggested by Deekay in the readme of the Colour Spectrum demo.

  • Freespin runs on 1571 drive in addition to 1541

  • C128 support of drive GPU required for Freespin demo

  • Improved sync detection. Freespin display a lot more stable (when it actually runs).

  • Fixed bug with VIA reset code that would lock drive if PB7 output was on.  Freespin no longer locks the drive after reset.

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  • Show correct frames/second in the frame title for all video chips, including simulated drive gpu.

  • Added sound support for Freespin demo.  note: Demo still does not run reliably every time yet in emulation but it is improving.

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  • Improved Freespin demo support.  Better drive sync detection. Displays graphical effects correctly (when it works)  warning: sometimes crashes the drive where the entire emulator needs to be closed and restarted.  Freespin support is still a work in progress.

  • To play the Freespin demo, after the drive code has loaded, select Drive GPU from Machine settings==> Model panel.  When screen turn blacks reattach the same disk image to start the demo.

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  • Added option to use disk drive as GPU for Freespin demo.  note: Not reliable and does not play sounds yet.

  • Some improvements to userport rs232 emulation.

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  • Option to disable userport rs232 modem emulation.  Allows connection to tcpser etc.

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  • Fix debugging of Z80 LD A,I and  LD A,R

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  • Added option to use disk drive as GPU for Freespin demo.  note: Not reliable and does not play sounds yet.

  • Some improvements to userport rs232 emulation.

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  • Fix disassembly of Z80 F9 toLD SP,HL

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  • ZX Spectrum - experimental SID option at port xxcf when xx is the SID register.  Currently when SID is enabled, beeper and AY are disabled.

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  • Updated undocument machine monitor IO command to dump c64/c128 registers.  e.g. io d500 will dump detailed c128 mmu values. io by itself will dump values only for all io registers.  note: the io command is still work in progress.

Show Previous Changes
  • Updated undocument machine monitor IO command to dump c64/c128 registers.  e.g. io d500 will dump detailed c128 mmu values. io by itself will dump values only for all io registers.  note: the io command is still work in progress.

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  • Fixed broken stand alone SID Player

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  • Improved Spectrum +2A contented memory and border update timing.  btime and contend NOP tests match real +3 Spectrum hardware

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  • C64/C128/VIC 20 - Reset machine if required for autoload

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  • Improve MEMPTR (Z80 WZ register) behaviour)

  • Include Z80 WZ register valuein debugger outputAllow 

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  • drop and drag of TZXfiles into ZX spectrum.

  • Allow loading of version 2, mode 4 Z80 snapshots

  • Fixed bug that could change value of the Z80 OUT (c),0 instruction if it was last instruction being executed beforea reset.

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  • Updates to contended memory timing of Z80 IN and OUTport instructions.

  • Adjust Spectrum +2A IRQ by 3 cycles.  fusetest results match other emulators but btime is out by 3 cycles compared to other emulators.  Need results from real hardware...

  • Improved partial decoding of port 7ffd for Spectrum +2A

  • TZX block type 2A and 33 implemented.

  • Disable tape traps when correct ROM is not banked in.

  • Minor adjustments to Spectrum +2A IRQ and contended memory timing

  • Start of Spectrum +2A support.

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  • Option for mono output of beeper and AY. (On by default)

  • Enabled saving of ZX spectrum z80 snapshot.

  • Fixed a bug with loading z80 files. (A/F and A'/F' were reversed)

  • Support for loading of 128K Z80 files.  (V2 hardware type 3 and V3 hardware type 4)

  • Include ZX spectrum models 16K, 48K NTSC, and plus 2.

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  • Adjust border update by one pixel.   Fixes BTIME timing

  • Loading TAP and TZX via load program automatically resets the emulation (in preparation of autorun.)  Loading TAP and TZX via Datasette menu does not  automatically reset the emulation (required for multi tape demos/games)

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  • Improved Z80 port access timing.  Fusetest passes all tests in Spectrum 48K and Spectrum 128K.

  • TZX Block type 15 support.

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  • Minor update to ULA snow effect.

  • Tape auto stop and trap options.

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  • Set Spectrum 128 clock to correct speed.

  • Set tape block pause time to correct value.

  • Improved TZX file support.  Included TZX files in tap loader

  • Fixed broken .sna file support for ZX Spectrum

  • Included missing IR contend memory cycles. Updates to snow effect.

  • Implemented TZX tape file support. (incomplete - only available under load program at this stage but will populate the cassette settings preview panel when loaded.)

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  • Minor tweak to snow effect

  • Snow effect extends over entire ULA memory access cycles

  • Can save ZX spectrum settings

  • Option to enable/disable snow effect.

  • Added ULA snow effect

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  • Fix port timing of Z80 OUTI, OUTD, OTIR and OTDR instructions.  ULA test scroll17 displays without jitter.

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  • Enableddrag and drop of files to ZX spectrum.

  • Writes to multiple ZX spectrum IO ports at same time allowed.  Displays scroll text above screen for scroll17 ULA test.

  • Slightly adjust default ZX spectrum screen position.--

  • Improved reading of floating bus during contended IO.

  • Fix bus timing of LD(IX+d),n and LD(IY+d),n Z80 instructions.  FPGA48all test displays correctly

  • Improved single stepping of instructions during ZX Spectrum contended memory.

  • show correct disassembly of indexed ALU Z80 instructions

  • Improved memory bus timing of EX (SP), HL.

  • Fixed debugging of memory when switching to ram1 with the machine monitor bank command

  • Fixed disassembling of LD (HL),r z80 instructions.

  • Improved timing of ZX spectrum border relative to screen.

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  • Implemented undocumented z80 instructionOUT (c),0 (ed71)

  • Show current TAP block in cassette settings.

  • Updated ZX spectrum icon.

  • Decrease voltage level of ZX spectrum tape data playback through speaker.

  • Disable tape player motor and sound from tape when MIC is reset for ZX spectrum.

  • Fixed screen size of ZX spectrum 128K.

  • ZX spectrum tape rewind and fast forward.

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  • Added option for normal load of TAP files.

  • Use correct ROM for Spectrum 48K.

  • Added option for ZX Spectrum 128.

  • Implemented Z80 interrupt mode 0.

  • Added ZX spectrum cursor key keyboard mapping

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  • Improve sound output of ZX Spectrum AY on higher sample rates

  • Fix floating bus behaviour for arkanoid. Sound no longer has unintended noise.

  • Fixed default gain for SID.  It was set as though digimax was connected by default meaning sound was playingat half the level it should have been.

  • Increased portaddress range of valid read/write to AY registers

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  • Allow loading of ZX Spectrum tap files.  No autoload at the moment, must use load"" enter after loading tap file(using the following keyboard sequence:- j, shift p, shift p, enter)

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  • All ZX spectrum timing tests pass with uncontended and contend memory.  Sidewize plays without flicker

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  • BOTH versions of Z64K. Fixed loading of all .d71 disks images.  Some were failing to load correctly if the BAM double sided flag was not set to $80.

  • Updated c128 Z80 port read and port write behaviour

  • Improved ZX spectrum beeper output

  • Fixed broken C64 CP/M

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  • Improvements to ZX spectrum contended memory timing.

  • Improved ZX spectrum floating bus behaviour. Arkanoid works.

  • Updated t-state timing of Z80 RLD, RRD and EX (SP),index instructions.

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  • Fixed monitor dumping of REU memory.

  • Updated flag behaviour for Z80 CCF and SCF instruction.

  • Updated some internal Z80 behaviour.  MEMPTR test program only fails 5 tests now.

  • Implemented undocumented Z80 Flag behaviour.  ZEXALL passes all tests.

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  • Z80 instructions INI, INIR,IND,INDR,OUTI,OTIR,OUTD,OTDR are now cycle exact

  • Fix copy highlighting length of Z80 monitor debugging

  • More improvements to timing of ZX Spectrum contended memory.

  • Z80 instructions CPI,CPIR,CPD, and CPDR are now cycle exact.

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  • Improved ZX Spectrum keyboard handling to handle all high byte address port range

  • More improvements to ZX Spectrumcontended memory timing.

  • Improved ZX Spectrum contented memory and contented  IO.  Full screen raster in Shock Megademo 3 shows correctly.  ULA test 3 and ULA test 3 modified show same output as reference screen from real ZX spectrum.

  • Improved floating bus behaviour.  Floatspy passes self test as OK.

  • Place 0xff on the bus for ZX spectrum Z80 interrupt mode 2

  • Implemented ZX Spectrum floating bus behaviour for disconnected IO reads.

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  • Add Custom and Gamepad joystick options for ZX Spectrum.

  • Improved Z80 instruction cycle exacttiming.

  • Fix number of raster lines for ZX Spectrum.  It was one less than it was meant to be.

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  • Correctly set Interrupt flag when loading z80 files.

  • Fixed Kensington direction mapping.

  • Kensington joystick support using numpad direction keys (0=fire).

  • Added ZX spectrum Beeper sound.

  • Partial v2 z80 file format support for ZX spectrum.

  • Updated some reading of io port behaviour.  Fixes unintended animation in Fairlight and Fairlight 2

  • Basic z80 file support. (v1 only).  Tested with Firelord and Fairlight. Both are in aplayable state.

  • ZX spectrum screen timing adjustments.

  • Backspace key

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  • Improved speed and display of memory and REU dumps in monitor

  • Update to REU floating bus behaviour.

  • Set correct REU size when using command line options

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  • Set flags correctly for LD A,I and LDA A,R (needs testing)

  • Fix bug with Z80 RES/SET instructions that got broken in previous release

  • Fix disassembly of Z80 DDCB and FDCB instructions

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  • Implemented missing Z80 instructions JP (IX) and JP (IY)

  • Implement missing Z80 instructions ld a,i (ed57) and in a,(*) (db).  Note: in a,(*) is not currently cycle exact so may cause issues with programs that require exact timing.  This will be fixed in next release.  Both of these instructions in addition to the HALT command require furthertesting. 

  • Fixed C128 that got broken in 10 February release

  • Set default emulation or application via General settings in Global settings Set default emulation or application via General settings in Global settings

  • Set default value of REU floating bus value to 255Slight improvement to REU timing.  Test b3 of REU Timing 2 passes. 

  • Improved VIC-II reset code and NTSC/PAL switching to prevent the emulator from ever being in an invalid state that couldpotentially cause it to crash.

  • Improved VIC-II reset code and NTSC/PAL switching to prevent the emulator from ever being in an invalid state that couldpotentially cause it to crash.

  • Fixed bug where VICII could crash emulator while doing a hard reset.  Always crashed when doing a hard resetusing 50/60Hz mode.

  • Save state of 50/60 Hz.

  • Include emulated computer name in window title bar

  • Show "paused" in title bar when emulator is paused.

  • Save Custom IC Glue Logic

  • Send labels from Assembler to emulated computer.

  • Implemented Z80 HALT command. *requires testing.

  • Fixed bug that could crash assembler when loading source code from file.

  • Confirm before exiting

  • Stand alone Assembler option

  • Enabled loading of t64 files into memory.  Need to type RUN and ENTER to execute program

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