Program Memory Size.
AT94K devices have a user configurable memory partition between the AVR Program memory and the data memory. The program and data SRAM is divided into three blocks: 10K x 16 dedicated program SRAM, 4K x 8 dedicated data SRAM, and 6K x 16 or 12K x 8 configurable SRAM, which may be swapped between program and data memory spaces in 2K x 16 or 4K x 8 partitions. This directive is used to specify the size of the program memory block.
.CSEGSIZE = 10 | 12 | 14 | 16.CSEGSIZE = 12 ; Specifies the program meory size as 12K x 16