summaryrefslogtreecommitdiff
path: root/home/farcall.asm
blob: cb87b1774be0d6ba6a25ce1a3a5a72c91d7e0824 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
FarCall_de::
; Call a:de.
; Preserves other registers.

	ld [hBuffer], a
	ld a, [hROMBank]
	push af
	ld a, [hBuffer]
	rst Bankswitch
	call .de
	jr ReturnFarCall

.de
	push de
	ret

FarCall_hl::
; Call a:hl.
; Preserves other registers.

	ld [hBuffer], a
	ld a, [hROMBank]
	push af
	ld a, [hBuffer]
	rst Bankswitch
	call FarJump_hl

ReturnFarCall::
; We want to retain the contents of f.
; To do this, we can pop to bc instead of af.

	ld a, b
	ld [wFarCallBCBuffer], a
	ld a, c
	ld [wFarCallBCBuffer + 1], a

; Restore the working bank.
	pop bc
	ld a, b
	rst Bankswitch

	ld a, [wFarCallBCBuffer]
	ld b, a
	ld a, [wFarCallBCBuffer + 1]
	ld c, a
	ret

FarJump_hl::
	jp hl