1#define nop andeq r0, r0
 2
 3.text
 4
 5b resetBase
 6b undefBase
 7b swiBase
 8b pabtBase
 9b dabtBase
10nop
11b irqBase
12b fiqBase
13
14resetBase:
15mov pc, #0x8000000
16
17swiBase:
18cmp    sp, #0
19moveq  sp, #0x04000000
20subeq  sp, #0x20
21stmfd  sp!, {lr}
22ldrb   r0, [lr, #-2]
23cmp    r0, #4
24bleq   IntrWait
25cmp    r0, #5
26bleq   IntrWait
27ldmfd  sp!, {lr}
28movs   pc, lr
29
30irqBase:
31stmfd  sp!, {r0-r3, r12, lr}
32mov    r0, #0x04000000
33add    lr, pc, #0
34ldr    pc, [r0, #-4]
35ldmfd  sp!, {r0-r3, r12, lr}
36subs   pc, lr, #4
37
38IntrWait:
39stmfd  sp!, {r2,lr}
40add    sp, #-4
41strh   r1, [sp, #0]
42IntrWaitLoop:
43mov    r2, #0x04000000
44add    r2, #0x200
45ldrh   r0, [r2, #0]
46strh   r0, [sp, #2]
47ldrh   r1, [sp, #0]
48orr    r1, r0, r1
49strh   r1, [r2, #0]
50mov    r0, #0x1F
51msr    cpsr, r0
52swi    #0x020000
53mov    r0, #0xD3
54msr    cpsr, r0
55mov    r0, #0x04000000
56ldrh   r2, [r0, #-8]
57ldrh   r1, [sp, #0]
58ands   r1, r2
59eorne  r1, r2
60strneh r1, [r0, #-8]
61ldrh   r0, [sp, #2]
62mov    r1, #0x04000000
63add    r1, #0x200
64strh   r0, [r1, #0]
65beq    IntrWaitLoop
66add    sp, #4
67ldmfd  sp!, {r2,pc}