Max Fast Memory In WinUAE

[CodyJarrett]

Toni - why is the maximum Fast memory possible in WinUAE 8 meg? Is it not easy to use more memory, especially when a lot of us have 512Mb in our PCs?

[Toni Wilen]

"Regular" fast memory is limited to 8MB (this is Amiga hardware limitation). Use Z3 fast for max 512MB of RAM...

[jmmijo]

Originally posted by Toni Wilen
"Regular" fast memory is limited to 8MB (this is Amiga hardware limitation). Use Z3 fast for max 512MB of RAM...

Also, isn't the Z3 Fast RAM supposed to be faster? And Toni, under Winuae does it indeed emulate faster? Just curious ;)

[CodyJarrett]

Doh! Thanks Toni...

[Toni Wilen]

Under UAE CPU's memory accesses aren't slowed down by bus contention yet and emulated "bus width" is always 32-bit. This means All RAM types' speed is equal. (and this also means Chip RAM is usually too fast..)

[jmmijo]

Makes sense, do you suppose this could be the cause of some compatibility with certain games? I mean this would not be considered cycle exact emulation would it?

[oldpx]

I have 32mb of ram on my Blizzard 1230-IV and it is displayed as fast ram under workbench. Anyone care to explain?:confused

[Toni Wilen]

I have 32mb of ram on my Blizzard 1230-IV and it is displayed as fast ram under workbench

Z3 Fast is 32-bit and located at 32-bit address space (>= 0x10000000), regular fast ram is 16-bit and located at 0x200000-0xa00000. Both are usually called "fast ram".

Makes sense, do you suppose this could be the cause of some compatibility with certain games

I am 110% sure it causes problems.

[oldpx]

Then some part (or all) of my 32mb of ram is indeed Z3. Does this cause incompatibilities even though I'm using a real Amiga?

[Toni Wilen]

Then some part (or all) of my 32mb of ram is indeed Z3. Does this cause incompatibilities even though I'm using a real Amiga?

There is no problems. I was replying to jmmijo's cycle-exact cpu memory access question. (sorry for bad quoting..)

All >8MB Fast RAM expansions are Z3 and need 32-bit addressing (68020 or better, 68EC020 and older support only 16MB address space)

[oldpx]

Thanks for the clarification.

[jmmijo]

Originally posted by Toni Wilen
All >8MB Fast RAM expansions are Z3 and need 32-bit addressing (68020 or better, 68EC020 and older support only 16MB address space)

and this means that any Z2 boards, in a real Amiga that is, that have RAM expansion on them are also considered 16-bit fast ram. One of the differences then between Z2 and Z3 boards is the address bus size on the Zorro bus connectors. Is this correct Toni?