20 lines
401 B
ArmAsm
20 lines
401 B
ArmAsm
.define Asp
|
|
|
|
! This subroutine adds an offset to the stackpointer,
|
|
! e.g. after the return from a procedurecall.
|
|
! The offset is in registerpair AX, and is added to the
|
|
! stackpointer.
|
|
|
|
|
|
Asp:
|
|
tay ! save A
|
|
txa ! get X
|
|
clc
|
|
adc SP+2 ! add adjustment (lowbyte)
|
|
sta SP+2 ! new stackpointer (lowbyte)
|
|
tya ! get A
|
|
adc SP+1 ! add adjustment (highbyte)
|
|
sta SP+1 ! get stackpointer (highbyte)
|
|
rts
|
|
|
|
|