Hi, Guenter,
I think we have not the documentation to address the LDM/SDM subject. In SDM mode, the code size is limited to 64K words, and data size is limited to 64K words, the pointer of data structure in C language is 16 bits. In LDM mode, the code size should be limited to 2**(21) or 2M words, the data size is limited to 2**(23) or 8M words.
Hope it can help you
BR
Xiangjun Rong