This prerelease is again mostly a floppy disk drive bugfix edition.

v0.00014

This prerelease is again mostly a floppy disk drive bugfix edition.

• Made the "HDMI: Zoom-in" option more useful. It now zooms in to the maximum area of those used by the usual ROMs. It may need some further small adjustments to improve aspect ratios, if possible.
• Switched to a more authentic editor ROM for the 8032. I noticed that the previous one only left one vertical pixel between text characters, instead of the 2 that it is supposed to do. You need to update the /pet/8032b.rom file on your sd-card to keep the rom file in sync with the builtin one.
• Make disk errors a bit more visible by using more red in the LED and less green. The activity LEDs for both drive now also (usually) don't light up at the same time, which reduces confusing colour combinations.
• More improvements/bug fixes in the floppy disk drive regarding track buffer management. One bug in the M2M framework contributed to this as well and was fixed (nr 52).

Bugfixes...

v0.00013

This prerelease is mostly a bugfix edition. Finding (hopefully good!) fixes for two problems took some time.

• Fixed the reset bug with the symptom that, after a reset, there was a chance that the HELP key did not work any more. (This was because the QNICE CPU was waiting forever on a hyperram bus transaction).
• Worked around the disk drive issues with write errors. The 8250 is no longer Read Only (and the 4040 also works better again).
• You can switch the disk drive type directly (it always reset automatically).
• Loadable disk drive ROMs since upstream supports this now.

Model 8296-D

v0.00012

This prerelease adds/changes, compared to v0.00011:

• Uses the MiSTer2MEGA65 framework version 2.0.1.
• Fixes the bug where the keyboard becomes unresponsive after leaving the menu.
• Adds 8296-style memory extension (extra 32 KB of RAM "under" the ROMs).
• The presence of the disk drive is now optional.
• New 8250 floppy disk drive type. Unfortunately there is an upstream bug, and this type is effectively Read Only for now.
  • When switching types, go via "disabled" as an intermediate step (this resets the drive).
  • You can still use disk images of type .D64 (174 848 bytes) for the 4040.
  • You can use disk images of types .D80 (533 248 bytes) and .D82 (1 066 496 bytes) for the 8250.
    When using a D80 disk image (single sided, for 8050 drives), the first disk access will result in an error. This is normal behaviour of the 8250 drive.
  • Use the correct disk image for the disk unit type.
  • Disk images are stored in Attic RAM.
• Together this makes the MegaPET a 8296-D. Although that actual model had a different CRT and so required a different Editor ROM.

Now with dual disk drive

v0.00011

This prerelease adds/changes, compared to v0.00010:

• Starts up as model 8032: with CRTC, 80 columns, B keyboard, 8032b.rom. Some people preferred this.
• Updated ColourPET editor ROM 4032n+colour.rom to cpet-c0-40-n-mega-wedge (2025-01-31).bin. Copy the new version to your sdcard.
• Imported 4040 dual disk drive from CBM-II_MiSTer core by Erik Scheffers. This drive is not considered final yet so there may be updates in the future.
• Loading custom drive ROMs is for now not possible (the feature is missing from the 4040's code).
• There are 3 LEDs to show (2 drive activity LEDs and the error LED). I tried to map them to the 2 halves of the M65's drive LED but you could not really see a difference between left and right in most cases. So I mapped them to colours: red = error, green = drive 0, blue = drive 1.
• The Power LED is yellow when the drive cache is dirty and/or being flushed. This previously was the task of the drive LED.

Colours!

v0.00010

This prerelease adds, compared to v0.00009:

• Steve Gray's ColourPET board. Try it with GridRunner. I have included a test version of an editor ROM set for 40 columns 4032n+colour.rom, specially created by Steve Gray for the MegaPET. Keep an eye on github for updates.
• You can now select 8, 16 or 32 KB as the basic memory size.
• 64 KB memory extension board, 8096-style. Not so well-tested but it seems ok.
• The optional second half of the character ROM can now be used (if it is 4 KB), by setting MA13 (poke 59520,12: poke 59521,3\*16). The MegaPET comes loaded with the character ROM from the SuperPET, which has ASCII and APL characters in the extra part. To go back to normal use poke 59520,12: 59521,1\*16.
• Similarly the screen as a whole can be inverted by unsetting MA12 (use poke 59521,0\*16 or 2\*16).
  These features only work with the CRTC, and these address bits may be repurposed in later PET models: for example, the HRE uses MA12.
• Incorporated upstream fixes from the to-be-released next version of the M2M framework, fixing the "barcode" issue that affects a small number of Mega65 revision 6 machines.

Full Changelog: v0.00009...v0.00010
Full Changelog: Rhialto/PET2001_MiSTer@v0.00009...v0.00010

80 columns

v0.00009

This prerelease adds, compared to v0.00007:

• 80 columns of text. Enabling this option automatically enables the CRTC too, but you need to load the 8032b.rom yourself. You will also need to enable the following new feature:
• B-type ("business") keyboard. By itself this is not so interesting, since with the symbolic mapping of the Mega-65 keyboard you don't notice much difference (but do refer to the keyboard mapping section below).
• 2001-style screen snow. This is enabled as part of "2001 screen blank etc". This option affects 2001-specific quirks as part of the "etcetera". At his time they are:
  • screen snow, when the CPU accesses screen memory at the same time as the video system.
  • the screen blanks when EOI is sent on the IEEE-488 bus. This is used by the ROM to mask the previous effect when scrolling (only the non-CRTC ROMs do this).
  • the 1 KB of screen memory $8000-$83FF is repeated 3 more times, up to $8FFF. Later models go only up to $87FF.
• I have extended the set of ROMs with B keyboard and 80 column ROMs. You can get more variants from the well-known Zimmers site.
• I am including a petcfg file which you can copy to the /PET directory on the sd-card. It will remember the menu selections. Unfortunately not the ROM file you loaded, so it is less useful than it could be.

Add CRTC

This version adds an optional CRTC.

Note that if the CRTC is enabled, it should be initialized or your screen will look weird. So you also need to select a ROM set which supports the CRTC, such as v0.00005/4032n.rom from the v0.00005 pre-release. And then press the reset button. This romset will also work if you don't have a CRTC but then of course you don't get the extra text spacing in lower case mode. Note also the changed aspect ratio of the text; this probably somewhat corresponds to the "fat-40 experience".

Tested with the timing programs from VICE bug #1954, and the A Bright Shining Star demo.

Video timing is now good

Racing-the-beam programs for CRTC-less models now work.
See test programs at VICE bug https://sourceforge.net/p/vice-emu/bugs/1954/ or PET's TRIP https://www.pouet.net/prod.php?which=95051 .

Cores for R3 and R6 included. See previous releases for ROM files etc, I'm not currently repeating them.

Loadable ROMs

I added some items to the menu and some of it even works. You can now load ROM sets; I added a few in the zip file.
For a true 2001 experience, turn the screen white-ish, enable screen blanking on EOI, load the 2001 character set (different in lower case mode!) and the 2001 ROMs. Too bad you can't reduce the memory size to 8 KB yet...

Now with sound!

Now with sound, which includes a generous amount of low-pass filtering. Otherwise you'd hear a high whine when many programs think they have turned off the sound (they merely set it to the highest frequency which typically wasn't audible on the speakers as used).

Enjoy Dromeda with sound, making it multi-media avant la lettre! (It moves and has sound, so: multimedia!)