Re: Need a really good ram unit test program

[BLuRry <brendan.robert@gmail.com>]

ftp://ftp.apple.asimov.net/pub/apple_II/images/disk_utils/diagnostics/

I tried various apple //e diagnostics from here, and so far JACE passes all of them.  Now I really don't have an explanation for random game crashes unless there's not a single one of these tests that track the program counter and CPU fetch behavior when flipping ram banks while the PC is in the affected bank.  It just doesn't make sense though.

-B

On Thursday, April 19, 2012 11:32:34 PM UTC-5, BLuRry wrote:
> Not to test memory, but really what I need is the ability to test the behavior of the MMU and all the softswitches related to it.  I keep getting random crashes in JACE in games that use AUX memory, and sometimes Prodos as well.  Though it's speculative, I think the most prudent thing to do is assert what is proper MMU behavior with a software-based test and compare results to a running physical machine.  Since there are some switches (for LC) that require being accessed TWICE before they allow writes, these are the sorts of things that should be tested in all, or at least most, possible combination.
> 
> Specifically, I get the impression that aux ram is being switched back to main ram and the program counter is not picking up the right opcode at the right time, or from the right place.  But its only a hunch.  It could be a similar issue but with language card banks.
> 
> Before undertaking such a labor of pain.. er... love, I wanted to see if anyone knew of any good diagnostic programs that tested language card ram and aux ram -- I might get what I need from something off the shelf.  
> 
> Any advice or tips greatly appreciated!
> 
> -Brendan