Epson S1C63358 Technical Manual page 25

(3) Subroutine calls use 4 words (for PC evacuation) in the stack area for 16-bit data (SP1). Interrupts use
4 words (for PC evacuation) in the stack area for 16-bit data (SP1) and 1 word (for F register evacua-
tion) in the stack area for 4-bit data.
S1C63358 TECHNICAL MANUAL
0000H
00FFH
0100H
01FFH
4 bits
Fig. 3.3.1 Configuration of data RAM
EPSON
CHAPTER 3: CPU, ROM, RAM
4-bit access area
(SP2 stack area)
4/16-bit access area
(SP1 stack area)
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