ST7MC1K2 Datasheet, PDF (41/371 Pages) STMicroelectronics – Clock, reset and supply management

ST7MC1K2-Auto, ST7MC1K6-Auto, ST7MC2S4-Auto, ST7MC2S6-Auto Central processing unit
pointed to by the SP. Then the other registers are stored in the next locations as shown in
Figure 8.
● When an interrupt is received, the SP is decremented and the context is pushed on the
stack.
● On return from interrupt, the SP is incremented and the context is popped from the
stack.
A subroutine call occupies two locations and an interrupt five locations in the stack area.
Figure 8. Stack manipulation example
Call
subroutine
Interrupt
event
Push Y
Pop Y
IRET
RET
or RSP
@ 0100h
uct(s) _SP
lete ^{Product(s) SP}
so ^rod _{@ 01FFh}
PCH
PCL
SP
CC
A
X
PCH
PCL
PCH
PCL
- ^{Ob te P Stack higher address = 01FFh}
O_O^b_b^s_s^o_o^l_l^e_e^t_t^ee ^{PPrroodduucctt((ss)) - Obsole Stackloweraddress= 0100h}
Y
SP
CC
A
X
PCH
PCL
PCH
PCL
CC
A
X
PCH
PCL ^SP
PCH
PCL
PCH
PCL ^SP
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