SuperH-based fx calculators
fx legacy: SMEM

Storage memory

It could be useful to know the storage memory's structure.


0x019F: void SMEM_Optimization();

Optimizes the storage memory without any intermediate dialog.
It is a bit annoying, when an addin recurrently uses storage memory, receives a memory-low error someday because of deleted wastes and forces the user to do an optimization manually. Perhaps a program-controlled SMEM-optimization could come in handy.

Syscall 0x019F cannot be called out of an addin without special precautions, because most probably the addin's code is elsewhere after optimization. Hence the addin will crash, when returning from SMEM_Optimization.
But it is possible to call it out of an optimization-proof place (this can be the stack!(tested), perhaps the main-memory(not tested yet)), call App_RegisterAddins afterwards and finally restart the addin with App_Start. All this has to be implemented as assembler-code (*.SRC).
Additionally the second callback-location, which defaults to OnAppCloseDefault, has to be accounted for. OnAppCloseDefault is part of the addin, too, and would crash after optimizaton.
OnAppCloseDefault calls the code according to the first callback-location (if defined), deinstalls the user-timers, closes the SMEM handles, calls syscall 0x218 (close find-handles) and finally jumps to syscall 0x244 (Bkey_SetAutoRepeatDefault). Normally the pointer to the second callback-handler can be set to zero.


0x020E: int SMEM_GetFilePos( int xhandle, int*pos );

Retrieves the current position of an opened storage memory file. xhandle is the Bfile-handle & 0xF0FFFFFF (0..4).
pos should be initialized with -1.
Returns the remaining bytes.
Returns a negative value, if an error occurred.


(19.03.2011 12:42:45)