Home Page Forums MAME MAME SVN builds - new driver flood

IIRC, with old PIO if I called port write with interrupt clear, it would mask interrupt requests completely, so no further interrupt was taken. That's why I was callin PIO port write only when interrupt line was active.

BTW, according to your changes descripton, handshaking inPIO was rewritten, but Megatouch doesn't use handshaking on PIO (I assume you are referring to READY lines). Maybe something else got broken then?

Mariusz.

Thank you Curt.

I was able to get it working again by changing the PIO implementation slightly and adding 2 scanline timers to assert/clear the vblank interrupts. Need to check that other drivers are still working tomorrow.

I don't understand how the driver could ever have worked in the first place

They broke because they were signaling a vblank interrupt (60Hz) at about 0.5Hz. The lack of keep-alive ints made the Z80 code crash and a watchdog reset occured.

The new PIO cares about the fact that the logic equation has to go false->true before an interrupt is signalled. The old PIO just banged in interrupts one after another until the V9938 bothered to toggle the VINT line, thus creating an illusion of a working system.

At least that's how I understood it, anyway it works now

great! the new pio code definitely beats the old one in every aspects

on an unrelated note, can anyone point me to a d64 image with error codes (either giving me the TOSEC name or the file CRC). they should be recognizable by their size, 175531 byte vs. 174848

I'd like to test the improved support, but I have no test cases

EDIT: @Curt: is there any reason to still have two different implementation of the mos6530 in the source? can we remove mos6530.c?

I'm not sure if nibconv supports d64 errors, you could convert a G64 game which has a simple sector error protection (like Ocean loader in Rambo 3 PAL).

http://c64preservation.com/dp.php?pg=database (search for "Ocean" protection)

The miot6530 should be converted to use devcb, so I left the mos6530 in there so you could do a quick copypaste

The last pio change broke the super80.

How?

you changed the mode 3 interrupts.

So, it is interrupting constantly and cannot get started.

super80 shows a black screen, while super80v shows the title then hangs before getting to the prompt.

I've reverted my copy of pio back to r7411, and it all works fine there.

Fixed super80.