ACA500plus Action Replay Function

I'm also interested. I saw yesterday a video with a guy saving states in a WHDLoad game with an ACA630 and HRTMon and was quite impressive!

To my knowledge, AR3 can't use "harddrives", but only floppy drives. I'd therefore switch to HRTmon for such hacking.

Please read the documentation in our Wiki. There's a lot of self-explaining menu items, and on top of that, every item is explained there. This support forum is not meant for employees of iComp to copy&paste the documentation that's available in the Wiki

HRTmon is an open-source piece of software with it's own documentation. I am not an expert on it's use myself - the Wiki just documents how to do settings on the ACA500plus to activate it on a press of the DisMo button. For further HRTmon documentation, I'd check the Aminet archive.

http://eab.abime.net/showthread.php?t=105022

Using it with WHDLoad could be an option...

Sorry for the confusion - I simply did not check the implementation details, but I have now talked to the programmer and have the final explanation why this is disabled and won't be enabled in a future update:

HRTmon must be considered a separate entity accessing the physical media, as it runs without the OS. This means that it does not know about new file systems (only supports FFS), it does not support any partition beyond the 4G barrier, and it accesses the hardware directly, not knowing what AmigaOS still has in it's buffers. Here's where the danger is: If you delete or rename a file from the HRTmon side, then return to operation under the OS and list a directory, bad things might happen if this dir has been read before and is still on the buffers. This also makes emulator+hardfile state saves impractical, as buffers and CF card *will* get out of sync, resuting in constellations like "save a state, then load a different state, but RAM contents are now from state file, with CF contents "from the futire". This will most certainly result in file system corruption or even a crash, as the CF contents and file system buffers don't match.

Making this "safe" would require to boot from floppy, only use an FFS partition in the lower 4G of the card and make sure that AmigaOS will never access the card. This doesn't sound practical at all, and is way too complicated to explain to anyone, unless he/she is a developer. Trouble is that HRTmon can't do additional "sanity tests", so if we'd enable HD commands, you'd always have this inherent danger.

So for the moment, the answer is "please use a floppy for safety reasons". We may make it switchable behind "multiple barriers of user confirmations", but are still discussing how this could be accomplished without opening too many doors for data corruption.

Quote from AmigaBob

Action Replay MK4

Did that even exist? I talked to the original developers for licensing, and I even got scans of their hand-written notes about the hardware, even an A1200 version that they were planning, but that never saw the light of day - probably because of the problems I described here. Not that 4G-sized media was a problem at the time, but the two-entities accessing a file system without knowing about each other certainly applied.