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Looks like uninitialised RAM, except bit 4 is still stuck high!

Now I'd be checking the CPU and SAM are still socketed ok - you mentioned reseating them before.

Some board photos might be informative... never know.

I can't offer to attempt repair, though there are others on here who might.

So, for a beginner, that means maybe i should check the connection of pin 4 of the VDG and follow the line to the RAM? Sorry to ask in that dump behavior. Well, it might not be this, but the first thing I'd be checking is pin 7 of the VDG (IC10) to pin 5 of the data latch chip (IC20, a 74LS273). It...

Looks like a fault between RAM chip for bit 4 through the video data latch through to DD4 (pin 7) on the VDG, seeing as everything else is functioning.

I guess a really dumb test would be to trigger an invalid instruction trap. Try POKE359,66 - on a 6809, it'll just mangle output into graphic characters, on a 6309 it'll crash :) An immediately observable difference I find is that a 6309 takes a while longer to initialise: when you turn the power on...

Just give your ASCII BASIC files an extension of ".asc" or ".bas", and attach them as with other tape images. XRoar will automatically packet it up to load with CLOAD.

Oh, and yes, going the other way, the easiest is to use "-lp-file outfile" and LLIST.

Oh, interesting. I added a 256x256 icon for 0.36. It's definitely visible in the 64-bit build (when I checked, anyway), but maybe 32-bit Windows doesn't support it?

Oh, weird! I could have sworn I pushed a new snapshot just before I wrote that message. Er, rectified

Two 16K ROMs, both resident at $8000+. Selection is with bit 2 of PIA1 side B. A HIGH value there selects the 32K BASIC ROM, a LOW value selects the 64K BASIC ROM.

There's an external pullup resistor on that line such that when configured as an input (power on PIA state), it'll be HIGH.

The second ROM contains code to run from $C000+, but when mapped it's actually just switched in in place of the normal 32K ROM. A loader stub is copied into RAM which copies the ROM ($8000+) into RAM ($C000+). The correct EXEC address to kick that off is 48000. That address is just a convenience - i...

It's good! Effective Semigraphics use, very playable. Will have to have a shuftie through it to see why it needs 64K though - maybe the map is drawn out in full into memory - twice would make sense too.