public .ovbgn, ovexit_
ext ovmain_,prctyp
dseg
ovstkpt: ds 2
saveret: ds 2
cseg
ovbgn:
pop h
pop h
pop h
pop h
sphl
pop b
; call prctyp ;8080 or z80 processor?
; jnc ovbgn10 ;jump if 8080
db 253,225,221,225 ;pop ix, pop iy for z80 processor
ovbgn10:
pop h
shld saveret
pop d
lxi h,ovret
push h
lxi h,0
dad sp
shld ovstkpt ;save stack pointer for ovexit
jmp ovmain_
ovret: xchg ;save return value
lhld saveret ;get return addr
push h ;place dummy overlay name ptr on stack
push h ;place return addr on stack
xchg ;restore return value to hl
ret ;return to caller
;
ovexit_:
lxi h,2 ;get return value
dad sp
mov e,m
inx h
mov d,m
lhld ovstkpt ;get original stack pointer
sphl ;and restore it
xchg
ret ;return back to root
end
