*** M E M O R U M ***

In practice. reading an unimplemented port usually returns whatever value was last on the data bus. If the port read is using an IN A,(ADDR) instruction, then that is the second byte of the opcode, i.e. the address of the port to read. There are a few places in the CFX-II ROM which rely upon this be...

Should you get around to placing an order for the connectors, I could have an interest in a few, irrespective of the progress on the MFX. Spread the cost / risk.

For those of us who have never heard of MiSTer, I did some Googling:

https://github.com/MiSTer-devel/Main_MiSTer/wiki

Martin, it was very generous for you to offer to host Memofest yet again. But as you say everyone is still feeling cautious. Hopefully by next year the situation will have improved.

I have produced a bit of a write-up of the porting process for Dave's site.

It is an example of how, sometimes, speed improvements can best be obtained by re-thinking the high-level design rather than low-level optimisations.

Thanks, fixed the link.

My GitHub Repository now contains the latest source code for all my versions of MEMU: * Linux X-Window * Linux Framebuffer - No GUI required * Raspberry Pi Linux - Use GPIOs to connect an MTX keyboard, Joystick or Printer * Bare-Metal Raspberry Pi - Now includes Raspberry Pi 4 and 400 support * Rasp...

As to skipping steps yes and no. There are routines to move a tile to a given row or column. These will get called for every tile, but if the tile is already in the correct position they will not have anything to do, and will return immediately. When trying to understand the code, you might find it ...

MTX version of the Fifteen Puzzle solver attached. Run the program and keep on pressing the space bar to step through the solution. Hopefully I have got all the typos out. It used the 'human' algorithm, which is almost certainly not the most efficient in terms of number of moves, but does not requir...

I have coded a prototype version of the 'human' algorithm. For me it was easiest to do this in Python, and enabled me to identify and solve the edge cases. Hopefully I have found them all. Having got this to work I should not find it too difficult to translate into MTX BASIC. If anyone is interested...