Uhh... I don't know where that 8KB of RAM at $0000-$8000 came from
Whoops, my bad. Hopefully this sets the situation straight:
Quote from: #omnimaga
[19:31:57] <+OmnomIRC> (O)<ztrumpet> calc84 [19:32:06] <+OmnomIRC> (O)<ztrumpet> Am I missing something? [19:32:39] <+OmnomIRC> (O)<calc84maniac> $0000-$3FFF is always ROM page 0 [19:33:04] <+OmnomIRC> (O)<ztrumpet> Let's see, what did I confuse here? [19:33:23] <+OmnomIRC> (O)<ztrumpet> What is at 0000 to 8000 then? [19:33:26] <+OmnomIRC> (O)<calc84maniac> there's $8000-$9D94 which is OS stuffs [19:33:49] <+OmnomIRC> (O)<calc84maniac> (plus some of that is saferam) [19:33:54] <+OmnomIRC> (O)<ztrumpet> right [19:34:04] <+OmnomIRC> (O)<ztrumpet> what's 0000 to 8000? [19:34:16] <+OmnomIRC> (O)<calc84maniac> normally, it's ROM [19:34:26] <+OmnomIRC> (O)<ztrumpet> Oh [19:34:31] <+OmnomIRC> (O)<ralphdspam> can you switch ram into it? [19:34:32] <+OmnomIRC> (O)<ztrumpet> That's one of the banks? [19:34:40] <+OmnomIRC> (O)<calc84maniac> two [19:34:46] <+OmnomIRC> (O)<ztrumpet> Wow, I feel really stupid now. [19:34:54] <+Runer112> 0000 to 3FFF is always ROM 0 [19:35:00] <+Runer112> so you can't switch RAM into there [19:35:20] <+OmnomIRC> (O)<ztrumpet> Then 4000 to 7FFF is another bank? [19:35:22] <+OmnomIRC> (O)<calc84maniac> and you can switch RAM into 4000-7FFF, but only on certain models [19:35:29] <+OmnomIRC> (O)<ztrumpet> What is there normally? [19:35:45] <+Runer112> there isn;t specifically a normal page there [19:35:51] <+Runer112> well [19:35:54] <+Runer112> I guess there technically is [19:35:56] <+OmnomIRC> (O)<calc84maniac> swapping ram there doesn't work on TI-83+BE or TI-84 Pocket.fr
Can I use this ram for rst hijacks in cpu-intensive programs, such as emulators? (Of course, I won't be able to use bcalls.)
Yes, but you must make sure to back it up somewhere. I'd recommend talking to calc84maniac about doing this - he is the only person I've heard of doing so, and he does it with his more recent versions of his GameBoy emulator.
Pertaining to the amount of RAM discussion, this is what the calcs have: 8 KB - Reserved for OS usage. I believe these are addresses 0000h to 8000h on Page 0. 24 KB - User Mem. Though there is technically some of this space (8000h to 9D95h) is claimed by the OS, the rest of it is for programs and other variables stored in RAM, as well as the VAT and some other OS stuff. 16 KB or 96 KB - "Extra RAM." This is used by the OS on some occasions, most notably with the BasePageTable for Apps on some OSes. If I remember correctly, the Math Print (MP) OSes also use some of this memory as well.
Also, there are things that can only be done with a goto, like starting a program over.
Depends on how it's structured. If you make the whole thing out of nested loops the right way, you can jump back to the being without a goto. A great example of this is tifreak's Sprite-2-Hex program. The whole thing is constructed out of nested While loops. When a menu item is selected, it runs a specific While var=value loop with that routine, then sets or resets the var as necessary to jump to the beginning, another routine or quit.
My TI Basic Homescreen Game Pack never uses a Goto. Or a Stop or Return for that matter.
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