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Old 15 November 2014, 22:29   #932
Toni Wilen
WinUAE developer
Join Date: Aug 2001
Location: Hämeenlinna/Finland
Age: 43
Posts: 20,627
It has crappy memory detection.

Originally Posted by mark_k View Post
Notice the bogus total memory figure and memory at 01000000.
ROM seems to support memory at 0x01000000->, detected by writing value to address zero, then some other value to 0x01000000, if address zero changes: no memory! If same, check 0x012000000 and so on.. Strange hardware if all non-existing address space gets aliased to address zero..

How is this memory supposed to be added to system? Manually? Did it even exist? Address is also "non-standard".

And the line for chip memory says 00000000-00100000 regardless of the actual amount of chip RAM (it's the same for 512KB and 2MB chip). I wonder whether that happens on real hardware.
Uses same stupid memory test. Emulation probably needs yet another switch (in advanced chipset).

Currently if ECS Agnus is selected with 512k chip RAM, hardware is emulated with "1M chip jumper" in enabled state and A26x0's memory detection does not handle it correctly. (If switch is added, I guess "1M chip jumper" off is better default)

("1M chip" jumper = jumper that selects if 512k slow ram is located at c00000 or 80000)

EDIT: fixes both and adds extra option.

EDIT2: 0x01000000 memory expansion is available as a separate board (DKB 2632) and it needs addmem-type program in startup-sequence. ROM monitor expansion ram detection is only used to support 'i' command, it is not used to add the memory or use it for any other "real" purposes.

Last edited by Toni Wilen; 16 November 2014 at 12:38.
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