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1 | /************************************* |
2 | Little John GP32 |
3 | File : ncpu.S |
4 | Authors : FCA author |
5 | modified and adapted by Yoyo. |
6 | adapted for fceu by notaz, 2007. |
7 | **************************************/ |
8 | |
9 | #include "ncpu.h" |
10 | |
11 | @@@ |
12 | @@@ Offets from REG_OP_TABLE |
13 | @@@ |
14 | #define OTOFFS_NES_RAM (nes_internal_ram - cpu_exec_table) |
15 | #define OTOFFS_NES_STACK (nes_stack - cpu_exec_table) |
16 | #define OTOFFS_NES_REGS (nes_registers - cpu_exec_table) |
17 | #define OTOFFS_PC_BASE (pc_base - cpu_exec_table) |
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18 | #define OTOFFS_IRQ_HOOK (MapIRQHook - cpu_exec_table) |
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19 | #define OTOFFS_TIMESTAMP (timestamp - cpu_exec_table) |
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20 | #define OTOFFS_X (X_ - cpu_exec_table) |
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21 | |
22 | @ fceu |
23 | #define FCEU_IQNMI 0x08 |
24 | #define FCEU_IQTEMP 0x80 |
25 | |
26 | |
27 | @@@@@@@@@@@@@@@@@@@@@@@@@@ |
28 | |
29 | |
30 | @ SECTION_FAST |
31 | SECTION_TEXT |
32 | ALIGN |
33 | |
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34 | /* |
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35 | bbbb: |
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36 | .ascii "ab_a: %04x" |
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37 | .byte 0x0a,0 |
38 | .align 4 |
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39 | stmfd sp!,{r0-r3,r12,lr} |
40 | mov r1,r0 |
41 | ldr r0,=bbbb |
42 | bl printf |
43 | ldmfd sp!,{r0-r3,r12,lr} |
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44 | */ |
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45 | |
46 | @@@ |
47 | @@@ r0 = Address (unbased) |
48 | @@@ uses REG_OP_TABLE; sets REG_PC; trashes r1,r2; keeps r0 |
49 | @@@ |
50 | .macro REBASE_PC |
51 | @ FIXME: do something with mem not in Page[]. |
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52 | @ stmfd sp!, {r0-r3,r12,lr} |
53 | @ mov r1, r0 |
54 | @ ldr r0, =bbbb |
55 | @ bl printf |
56 | @ ldmfd sp!, {r0-r3,r12,lr} |
57 | |
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58 | cmp r0, #0x2000 |
59 | ldrge r1, =Page |
60 | movge r2, r0, lsr #11 |
61 | ldrge r2, [r1, r2, lsl #2] |
62 | andlt r2, r0, #0xf800 |
63 | addlt r1, REG_OP_TABLE, #OTOFFS_NES_RAM |
64 | sublt r2, r1, r2 |
65 | str r2, [REG_OP_TABLE, #OTOFFS_PC_BASE] |
66 | add REG_PC, r2, r0 |
67 | .endm |
68 | |
69 | |
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70 | @ updates fceu "timestamp" variable |
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71 | @ loads cycles to reg, reg!=r1, trashes r1, kills flags |
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72 | .macro FLUSH_TIMESTAMP reg |
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73 | ands \reg, REG_CYCLE, #0xff |
74 | beq 1f |
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75 | ldr r1, [REG_OP_TABLE, #OTOFFS_TIMESTAMP] |
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76 | orr REG_CYCLE, REG_CYCLE, \reg, lsl #8 @ put cycles for do_irq_hook |
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77 | add r1, r1, \reg |
78 | bic REG_CYCLE, REG_CYCLE, #0xff |
79 | str r1, [REG_OP_TABLE, #OTOFFS_TIMESTAMP] |
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80 | 1: |
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81 | .endm |
82 | |
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83 | |
84 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
85 | @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
86 | @@@ |
87 | @@@ CYCLE_NEXT |
88 | @@@ |
89 |