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Command line option "-ram KBYTES" seems to be broken with v0.21. Using '-ram' with anything less than 64 for the coco causes it to freeze.

This is the actual command line. This works perfectly under v0.18.

zephyr wrote:Command line option "-ram KBYTES" seems to be broken with v0.21. Using '-ram' with anything less than 64 for the coco causes it to freeze.

Ta for that, found the issue: I'm comparing the translated address (since supporting SAM RAM size config) against the limit instead of the untranslated one.

In case you're interested:

RAM can be connected to the SAM with three different layouts: 4K, 16K and 64K. Dragons only ever use the 64K layout (however much RAM they have, it's just how it's organised). But you can change the SAM's configuration and then RAM accesses start going to different physical locations (because the underlying layout hasn't changed, but the addresses being sent to them have). I suspect that beyond my test case, nobody will ever have bothered to play with that, but it was fun to implement

ramtest.cas - test utility, should work on XRoar and real Dragon 64 (or probably 64K CoCo).

ramtest.txt - what to expect if it's working.

Thanks for the quick and helpful reply. The -ram feature of xroar is very important to me as I like to emulate 4K COCO, 32K COCO 1, and 64K COCO 2 machines for testing my programs.