Z64K developer William McCabe has been hard at working updating Z64K.
This is an updated release of v1.2.4 – [Build 20200716.1329]
The following changes have been made since I last updated this application.


25 July – Version 2 of Z64K only

  • Atari 2600 drop and drag cartridge
  • Save machine model settings (c64 and c128 only)

16 July

  • * Include 8562 (NTSC) and 8565 (PAL) grey dot options of VICII for C64. Rename C128 VICIIe options to 8564 (NTSC) and 8566 (PAL). Removed 6567R56A (old NTSC) option for C128. *Version 2 of Z64K Only
  • Fixed IRQ timing for CBM drive 1571 .  Timera.prg passes from the VICE test repository

12 July – Version 2 of Z64K only

  • C128 VICII uses correct RAM block when MMU RAM banks 2 & 3 are enabled.
  • Fixed fatal error when attempting to start stand alone SID player caused by 6 July update .

11 July – Version 2 of Z64K only

  • fixed ROM handling for VIC 20. Fixes NTSC mode and Custom ROMs.
  • fixed load address out of range when loading file with machine monitor.

7 July – Version 2 of Z64K only

  • Fixed bug with ROM configuration which caused a fatal error with C128 emulation if settings were opened before starting the emulation.

6 July- Version 2 of Z64K only

  • Fix timing of CPM cartridge when using C128 emulation.
  • Fix debugging output of CPM cartridge.
  • All screen attributes are immediately refreshed when the emulator is paused the same as when the emulation is running normally.
  • Debug mode of screen available when the machine monitor is active which shows progress of current frame being generated.  A white dot shows current position of raster beam.

28 June

  • Support for the new format of HVSC songlengths.md5 with SID player

27 June – Version 2 of Z64K only

  • Fixed bug with C128 PIA where zero page and page 1 were not immediately updated when PIA RAM banks updated. piaglobe test program works without glitches now.

21 June – Version 2 of Z64K only

  • Some internationalization support.  Available in Global settings ==> Language

20 June – Version 2 of Z64K only

  • Fixed play/pause button of SID Player to be able to start playing again after being paused.

10 June

  • Mirror 1541 VIA  registers across entire range ($1800-$1bfff and $1c00-$1fff) – allows latest Krill loaders to work

9 June – Version 2 of Z64K only

  • re-enabled code I forgot to enable after implementing some updates to d030 testbit behaviour.  The disabled code was causing a fatal crash of c128 if testbit was set but not reset. e.g. poke 53296,2

8 June – Version 2 of Z64K only

  • Fixed stuck bit behaviour for REU size 128KB (1700) and 256KB (1764)

7 June – Version 2 of Z64K only

  • Customisable REU ram sizes
  • Included some missing Z80 opcodes.

6 June – Version 2 of Z64K only

  • Fixed bug that caused cartridges with relocatable IO to disconnect if being swapped to a lower IO range. (DIGIMAX, Swiftlink and PIA)
  • Display correct file size in disk preview for files greater than 255 blocks
  • Option for8 bit userport DAC

4 June

  • Fixed bug with VDC where latches would sometimes not reload during vertical scrolling of bitmap screen

3 June – Version 2 of Z64K only

  • Fixed a bug with the SID selection UI sometimes not updating the SIDIO correctly.

2 June – Version 2 of Z64K only

  • Support for up to 8 SID chips! Tested with The tuneful EIGHT which runs at full speed without glitches on my system but slower systems may struggle with all eight SIDs active at the same time.Option via settings ==>Machine Settings==>SID==>STEREO SID.

    Following is an example of the command line options to start The tuneful EIGHT with eight SID chips active (7 extra SID chips) and 8580 (sidenginemodel 257) selected:-

    z64k.jar c64 -stereosid 7 -sid2address d420 -sid3address d480 -sid4address d4a0 -sid5address d500 -sid6address d520 -sid7address d580 -sid8address d5a0 -sidenginemodel 257 D:\c64\test\prg\the-tuneful-eight.prg

  • Fixed command line option for -sidenginemodel  when selecting 8580 at startup.

31 May -Version 2 of Z64K only

  • Include cartridge image in snapshots

30 May -Version 2 of Z64K only

  • c128 ROM revision selection
  • ROM select all
  • VIC 20 bug fix when swapping NTSC/PAL
  • screenshot menu item
  •  Hotkey help text

29 May – Version 2 of Z64K only

  • enable file drag and drop.

28 May – Version 2 of Z64K only

  • Customisable joystick keymapping available via Settings==>Machine settings==>Controllers for all emulations.
  • Machine monitor help text for individual commands.
  • Support for Action Replay 2, 3 and 4 CRT cartridge formats,

23 May-Version 2 of Z64K only

  • Added help (?)command to machine monitor (WIP) – shows most but not all available commands

22 May

  • Improved Retro Replay status flag
  • Fixed bug with bank selection for Retro Replay Cartridge.
  • Added option to allow flashing of Retro Replay Cartridge  (Version 2 of Z64K only)

21 May -Version 2 of Z64K only

  • Improved DMA timing of REU. All tests in VICE test repository pass.

20 May – Version 2 of Z64K only

  •  Improvements to REU emulation.
    – rmw-trigger tests pass.
    – DMA timing stays at 1Mhz when C128 in 2Mhz mode.
  • Added support for Atomic Power, Super Snapshot V4 and Snapshot64 CRT types.
    Full list of currently supported CRT types in version 2:-
    0 – NORMAL
    5 – OCEANTYPE1
    6 – EXPERT
    7 – FUNPLAY
    17 – DINAMIC
    18 – ZAXXON
    19 – MAGICDESK
    21 – COMAL80
    32 – EASYFLASH
    47 – SNAPSHOT64
    53 – PAGEFOX
    60 – GMOD2

18 May

  • Fixed fatal error when REU DMA occurred before assigning a value to REU register 6

15 May

  • Fixed Comal80 CRT type
  • Fixed Magic Desk CRT type

12 May

  • Change LXA magic number back to 0xee to match my real hardware. Cracked versions of Wizball work again.

9 May

  • Can insert Retro Replay and REU at thesame time (Version 2 of Z64K only)

8 May

  • Added Retro Replay CRT support

5 May

  • Updated magic constant for 6502  LXA. LXAand FLIBUG tests pass from the VICE test repository
  • Minor fix to interrupt trigger timing for CIA SDR so it triggers the same time as SDR is set (4 cycle delay).  cia-sp-test-oneshot-old.prg passes now which means all VICE test repository tests pass.

4 May

  • More updates to CIA SDR flag behaviour so cia-sdr-icr-new and cia-sdr-icr-old test programs pass.
  • Some improvements to the CIASDR flag behaviour based on the cia-sdr-icr-new.prg test program in the VICE test repository.

1 May

  • Removed test code I forgot to remove from MOS 6526 that was causing some disk loaders to fail.  Higher Level loader between parts works now.
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