Apple IIe Core for the MEGA65 – Alpha 3

What's New

• Disk loading is significantly improved ( internal refactoring was performed to improve reliability and stability )
  
• Disk write protect support.
  
• Mockingboard support.
  
• Display options (colour, green/amber phosphor and monochrome toggle )
  
• 65C02 / 6502 toggle ( triggers reset when toggled )

Current Limitations
--------------------

• HDD support ( not implemented )
  
• Joystick support ( implemented in the core but not interfaced )
  
• Serial support ( implemented in the core but not tested )
  
• Mouse support ( implemented in the core but not interfaced )

Note:
At present, only .nib images are officially supported.
If you only have .dsk images, you can convert them using dsk2nib:

Source:
https://github.com/slotek/dsk2nib
Compile with: gcc -o dsk2nib dsk2nib.c

The next alpha release will include further OSD options:

• Color palette toggles
  
• Video Mode ( PAL / NTSC )
  
• Romswitch region toggle ( ie.. US/UK )

Planned additions include:
Feasibility into supporting additional disk image formats without requiring manual conversion ( needs further research )
Add a keyboard layout toggle to support MEGA65-specific key mapping

Heiße Liebe für den Freezer

The freezer menu has been rewritten for llvm-mos for greatly reduced file sizes and significant more room for new features, 30-60% reduction. I used the chance to add a few new features to MONITOR:

• 45GS02 assembler and disassembler
  
• Bit editor with named hardware registers and bits from the core (iomap.txt)
  
• Pixel viewer, hunt, fill, copy, compare.

The rewrite surfaced and fixed several bugs and dead code in the original. Code quality is maintained by strict compiler warnings; static analysis, CI workflow, and tests running on host or in Xemu using the serial interface to drive emulated user input. See https://github.com/mlund/mega65-freezer for more information and snapshot M65 files for the SD card. Note that this is fully unofficial, use at your own risk.

Sinclair QL Core for the MEGA65 – Milestone 2, Phase A

Following up on Milestone 1: the Sinclair QL core can now read real microdrive (.MDV) images on real hardware — DIR and LRUN both work reliably, including sustained reads of complete programs.

The bug hunt took a while: after several builds chasing what looked like a timing/race-condition issue in the microdrive controller (and fixing a few genuine bugs along the way — a loader signal that needed to be a level instead of a pulse, a missing CDC reset, video-contention wait-states leaking into I/O), the real culprit turned out to be corrupted test images, not the RTL. Built a checksum verifier/repair tool to confirm and fix it.

End result: Chess is now fully playable, loaded straight from a real microdrive image. ♟️

Also added a synthesized motor hum for the microdrive, gated by real drive activity.

What's left for Milestone 2: write support, migrating the microdrive buffer from BRAM to HyperRAM, and expanding from one drive to multiple units.

Looking ahead to Milestone 3: the full memory options (128KB/640KB/4096KB) and CPU speed modes (16MHz/24MHz/Full), all backed by HyperRAM.

Full write-up and photos in the thread: Sinclair QL Core QL4M65.