In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Tony Leyland wrote:

Hi,

I've come back to developing on the SX after a 6 month break and now find SX/B to be a fantastic product.  So much
so that I've now switched from developing completely in Assember, to using SX/B as my main environment and using
Assember routines where needed.

I'd like to ask, is there some documentation somewhere that explains the locations in memory that are used within SX/B
for variable storage and any other memory used for the inner workings of SX/B ?

The reason I ask is that I have (within a ASM -> ENDASM section) memory management routines that allow me to allocate
a contigous logical block of memory (like an array - up to 100bytes on the SX28) that I can access from Assember or SX/B.
The memory bank switching is done all for me in the background, when I'm accessing elements in the logical block. At the moment
memory allocation grows down from the topmost memory location (like a Stack).

So if I ask the memory manager to allocate 30 bytes for me, then the last byte of this logical array is situated at the topmost memory
location of the SX device and the 1st one 30 bytes down in memory from there.  If I then ask for another 40 bytes, then the end of this new logic
array is the memory location just before that of the 1st byte of the previously allocated logical array.

Sorry for the long explaination, but I wanted to explain what I'm trying to acheive, as I do not want to overwrite any memory
locations that SX/B uses itself.  I was wondering, if there was a read only parameter that I could read to obtain the last memory
location SX/B is currently using - due to the various VAR declarations). 

I'm under the impression that SX/B uses memory certain locations at top of RAM for I/O port parameters.  If I could ask if anyone
knows anything about this, then I would appreciate it as I'd be able to adjust my memory manager to set it's topmost area of available
storage to the byte just below the space used internally by SX/B.  I would then also stop arrays from being created that come down and interfere
with the storage for the VARS in SX/B.

Thanks for you help,
Tony

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