The short addressing (saddr) access method uses the short variants of the load and store instructions, SLD and SST. These instructions are smaller than the standard LD and ST instructions.

The assembler label __iar_static_base$$EP is located at the beginning of the 256 byte memory area that can be reached using the short load and store instructions. The processor register EP (R30) is used as a base pointer to this area. Note that when you are using a data models without short addressing, the EP register is instead a pointer to the frame on the stack.

The source code needed to store a value to saddr memory is:

         sst.w   R1, relep(x)[ep]

This instruction can only reach 256 bytes. When using byte access, it is limited to 128 bytes. This is the reason for the corresponding limitation on the data for the saddr memory type.