51 lines
716 B
ArmAsm
51 lines
716 B
ArmAsm
|
.define .loi
|
||
|
|
|
||
|
|
! Load indirect
|
||
|
|
! Expects in de-registers: number of bytes to be loaded
|
||
|
|
! (this number should be 1 or even )
|
||
|
|
! Expects on stack: base address
|
||
|
|
! Yields on stack: result
|
||
|
|
|
||
|
|
.loi: pop h
|
||
|
|
shld .retadr
|
||
|
|
mov l,c ! free bc for scratch
|
||
|
|
mov h,b
|
||
|
|
shld .bcreg
|
||
|
|
|
||
|
|
pop h ! hl = base address
|
||
|
|
dad d ! hl = load pointer
|
||
|
|
xra a ! clear carry bit
|
||
|
|
mov a,d ! divide d by 2
|
||
|
|
rar
|
||
|
|
mov d,a
|
||
|
|
mov a,e
|
||
|
|
rar
|
||
|
|
mov e,a
|
||
|
|
jnc 1f
|
||
|
|
|
||
|
|
! if 1 byte has to be loaded only:
|
||
|
|
mov a,d
|
||
|
|
ora e
|
||
|
|
cnz eoddz ! trap if number is odd and <> 1
|
||
|
|
dcx h
|
||
|
|
mov c,m
|
||
|
|
mvi b,0
|
||
|
|
push b
|
||
|
|
jmp 2f
|
||
|
|
|
||
|
|
1: dcx h
|
||
|
|
mov b,m
|
||
|
|
dcx h
|
||
|
|
mov c,m
|
||
|
|
push b
|
||
|
|
dcx d ! is count exhausted?
|
||
|
|
mov a,d
|
||
|
|
ora e
|
||
|
|
jnz 1b
|
||
|
|
|
||
|
|
2: lhld .bcreg
|
||
|
|
mov c,l
|
||
|
|
mov b,h
|
||
|
|
lhld .retadr
|
||
|
|
pchl
|