exxos's Atari, Amiga & retro forum

Anyway, here's a gratuitous glamour shot...

stephen_usher wrote: ↑Fri Nov 20, 2020 10:38 pm According to Motorola, asserting /HALT on the 68000 makes the address and data lines go high impedance, i.e. they stop being connected to the pins electrically in effect.

Seeing as both sockets are for a 68000 compatible processor any interface logic between the socket and accelerated processor would need to follow the 68000 on the machine side of the interface.

Yes, sorry, I got that backwards. It’s the bus control lines that are still driven high. But they sound like the ones you’re switching, so no dramas.

To half answer a question you posed a couple of times, I’ve only ever treated HALT as a write line without trouble yet appearing because of it. Not sure of the ST spec itself.

BW

Well, 512K ROMs seem to work, however the EmuTOS snapshot from a couple of days ago crashes on a standard ST (without Alt-RAM) when it tries to go to the desktop and access 0x400000. (It puts up the hour glass and then after a while it bus errors.) Looks like a bug.

However, I think that's probably a successful test.

Seeing as the board seems to be fully operational I may well remove the CPU socket on the motherboard and solder this board directly on the motherboard perminently. This will reduce the height by approximately 5mm. That's about half the amount I need to reduce in total to get the TF536 to fit under the keyboard.

Oops! The latest 256K image doesn't like the same thing.

If I boot holding Control down I get to the desktop but otherwise a crash trying to access 0x400000...

It's CONTROL.ACC ! Disable that and I get to the desktop. Definitely looks like an incompatability there.

Let's try the 512K ROM again... and that works.

stephen_usher wrote: ↑Sat Nov 21, 2020 11:07 am If I boot holding Control down I get to the desktop but otherwise a crash trying to access 0x400000...
It's CONTROL.ACC ! Disable that and I get to the desktop. Definitely looks like an incompatability there.

And even a documented one:
https://github.com/emutos/emutos/blob/a ... e.txt#L166

Ah, I see.

Unfortunately the other control panels are larger and generally don't work with memory tight games.

Anyway, I can report to the EmuTOS team that the partition scanning fix works and my UltraSATAN drives mount correctly.

Planning to test TF536 with PAK-TOS (512K)?

I can try that, once the TF returns.

Do you have a link?

Maybe someone can copy them over to the downloads section ?