Cyprian wrote: 19 May 2024 20:17
I know that Atari TT can have e.g. 10MB ST-RAM
ST/STE SHIFTER/MMU are limited to 4MB
Yeah they limited by hardware. Though I was more thinking what TOS version had more than 4MB. Not sure what OS the TT has , assume 306 ?
There is 'Maddalt' function: https://freemint.github.io/tos.hyp/en/g ... ml#Maddalt " »Inform GEMDOS of alternative memory« - Register 'Alternative' RAM with GEMDOS. "
It is used to add more than 4 RAM to the TOS memory pool and it was implemented in GEMDOS 0.19 (TOS 2.x)
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Cyprian wrote: 19 May 2024 21:26
There is 'Maddalt' function: https://freemint.github.io/tos.hyp/en/g ... ml#Maddalt " »Inform GEMDOS of alternative memory« - Register 'Alternative' RAM with GEMDOS. "
It is used to add more than 4 RAM to the TOS memory pool and it was implemented in GEMDOS 0.19 (TOS 2.x)
Yes indeed, but normally that is alt-ram whch is bolted onto the 68000 and needs PRG flags set. But what I am talking about is, pure ST RAM. In that would TOS itself see more than 4MB if it was installed..
Thinking about it, you normally have to boot the system without alt-ram enabled because TOS would try and allocate video RAM in alt-ram which results in a black screen. So then Maddalt is used to allocate the RAM and the shifter still gets limited to 4MB. It is a bit messy.. But this to me basically insinuates that TOS does actually check for more than 4MB STRAM.