What is E-Data Memory?

Question

In the Casio watches in says E-Data Memory what is this?

Answer 1

Extended Data Memory
It is a memory section of a CPU.

"EDATA = Extended Data. This is a superset of DATA and IDATA areas. P89C669 has 1280 bytes of SRAM in EDATA memory.
The added area may be accessed only as Stack and via indirect addressing using Universal Pointers. The Stack
may reside in the extended area if enabled to do so. EDATA content can be accessed anytime using EMOV
instruction regardless of bit EAM in MXCON."