68k vector table: Difference between revisions
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The vector table consists of a 256 bytes long vector list specific to the [[68k]]. | |||
== For cartridge systems == | Each vector is a 32-bit address, meaning the table holds '''64 vectors'''. Each entry is used by the 68k in precise cases. | ||
All bootable 68k programs must have a vector table at their very beginning. The [[system ROM]] and games have their own. | |||
Is $C00426 an universal [[BIOS calls|BIOS call]] for a complete reset ? | |||
=Stack frames= | |||
See [[68k exception handling]]. | |||
==Format A== | |||
{|class="wikitable" | |||
!Offset from SP | |||
!Size | |||
!Value | |||
|- | |||
| +0 | |||
|Word | |||
|Flags:{{16BitRegister| |11|0:Write 1:Read |1|0:Instruction|1|Function code|3}} | |||
|- | |||
| +2 | |||
|Longword | |||
|Access address | |||
|- | |||
| +6 | |||
|Word | |||
|IR | |||
|- | |||
| +8 | |||
|Word | |||
|SR | |||
|- | |||
| +10 | |||
|Longword | |||
|PC | |||
|} | |||
==Format B== | |||
{|class="wikitable" | |||
!Offset from SP | |||
!Size | |||
!Value | |||
|- | |||
| +0 | |||
|Word | |||
|SR | |||
|- | |||
| +2 | |||
|Longword | |||
|PC | |||
|} | |||
=Vector list= | |||
{|class="regdef" | |||
|'''Vector #''' | |||
|'''Address''' | |||
|'''Exception name''' | |||
|'''Trigger condition''' | |||
|'''[[68k stack frames|Stack frame]]''' | |||
|- | |||
|0 | |||
|000000 | |||
|Reset SP | |||
|Not really a vector. Used to initialize the stack pointer. | |||
| | |||
|- | |||
|1 | |||
|000004 | |||
|Reset PC | |||
|Reset/startup | |||
| | |||
|- | |||
|2 | |||
|000008 | |||
|Bus error | |||
|Bus cycle couldn't complete properly. | |||
|A | |||
|- | |||
|3 | |||
|00000C | |||
|Address error | |||
|Misaligned (odd) word or longword memory access. | |||
|A | |||
|- | |||
|4 | |||
|000010 | |||
|Illegal instruction | |||
|Tried executing an invalid opcode. | |||
|B | |||
|- | |||
|5 | |||
|000014 | |||
|Division by zero | |||
|DIVUed or DIVSed by zero. | |||
|B | |||
|- | |||
|6 | |||
|000018 | |||
|CHK instruction | |||
|CHK resulted in "out of bounds". | |||
|B | |||
|- | |||
|7 | |||
|00001C | |||
|TRAPV instruction | |||
|TRAPV with overflow flag set. | |||
|B | |||
|- | |||
|8 | |||
|000020 | |||
|Privilege violation | |||
|Use of privileged instruction. Never happens on the NeoGeo since the 68k always runs in supervisor mode. | |||
|B | |||
|- | |||
|9 | |||
|000024 | |||
|Trace | |||
|After each executed instruction when 68k is in trace mode (debugger function). | |||
|B | |||
|- | |||
|10 | |||
|000028 | |||
|Unimplemented instruction (line A) | |||
|Used to implement 680xx instructions in software. Not used on the NeoGeo. | |||
|B | |||
|- | |||
|11 | |||
|00002C | |||
|Unimplemented instruction (line F) | |||
|Used to implement 680xx instructions in software. Not used on the NeoGeo. | |||
|B | |||
|- | |||
|12 | |||
|000030 | |||
|rowspan=3|Reserved/Unused on 68000 | |||
|rowspan=3| | |||
|rowspan=3| | |||
|- | |||
|13 | |||
|000034 | |||
|- | |||
|14 | |||
|000038 | |||
|- | |||
|15 | |||
|00003C | |||
|Uninitialized interrupt vector | |||
|Default vector used by uninitialized peripherals. | |||
|B? | |||
|- | |||
|16 | |||
|000040 | |||
|rowspan=8|Reserved | |||
|rowspan=5| | |||
|rowspan=8| | |||
|- | |||
|17 | |||
|000044 | |||
|- | |||
|18 | |||
|000048 | |||
|- | |||
|19 | |||
|00004C | |||
|- | |||
|20 | |||
|000050 | |||
|- | |||
|21 | |||
|000054 | |||
|rowspan="3"|Normally reserved but used on the NeoGeo CD. See [[68k interrupts]]. | |||
|- | |||
|22 | |||
|000058 | |||
|- | |||
|23 | |||
|00005C | |||
|- | |||
|24 | |||
|000060 | |||
|Spurious interrupt | |||
|No acknowledge from hardware. | |||
| | |||
|- | |||
|25 | |||
|000064 | |||
|Level 1 [[68k interrupts|interrupt]] autovector | |||
|[[68k interrupts|V-Blank]] (cart) / [[Timer interrupt]] (CD). | |||
| | |||
|- | |||
|26 | |||
|000068 | |||
|Level 2 interrupt autovector | |||
|Timer interrupt (cart) / V-Blank (CD). | |||
| | |||
|- | |||
|27 | |||
|00006C | |||
|Level 3 interrupt autovector | |||
|Cold boot (cart). | |||
| | |||
|- | |||
|28 | |||
|000070 | |||
|Level 4 interrupt autovector | |||
|Not used on the NeoGeo. | |||
| | |||
|- | |||
|29 | |||
|000074 | |||
|Level 5 interrupt autovector | |||
|Not used on the NeoGeo. | |||
| | |||
|- | |||
|30 | |||
|000078 | |||
|Level 6 interrupt autovector | |||
|Not used on the NeoGeo. | |||
| | |||
|- | |||
|31 | |||
|00007C | |||
|Level 7 interrupt autovector | |||
|Not used on the NeoGeo. | |||
| | |||
|- | |||
|32 | |||
|000080 | |||
|TRAP #0~15 | |||
|TRAP instructions. | |||
|2 | |||
|- | |||
|48~63 | |||
|0000C0~0000FC | |||
|Reserved/Unused on 68000 | |||
| | |||
| | |||
|- | |||
|64~255 | |||
|000100~0003FF | |||
|User interrupt vectors | |||
| | |||
| | |||
|} | |||
=Templates= | |||
==For cartridge systems== | |||
<syntaxhighlight> | <syntaxhighlight> | ||
org $0 | org $0 | ||
Line 34: | Line 284: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
== For CD systems == | ==For CD systems== | ||
<syntaxhighlight> | <syntaxhighlight> | ||
org $0 | org $0 | ||
Line 55: | Line 305: | ||
</syntaxhighlight> | </syntaxhighlight> | ||
[[Category:Base system]] | |||
[[Category:Code]] | [[Category:Code]] |
Latest revision as of 16:01, 30 July 2018
The vector table consists of a 256 bytes long vector list specific to the 68k.
Each vector is a 32-bit address, meaning the table holds 64 vectors. Each entry is used by the 68k in precise cases.
All bootable 68k programs must have a vector table at their very beginning. The system ROM and games have their own.
Is $C00426 an universal BIOS call for a complete reset ?
Stack frames
Format A
Offset from SP | Size | Value | ||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
+0 | Word | Flags:
| ||||||||||||||||||||||||||||||||||
+2 | Longword | Access address | ||||||||||||||||||||||||||||||||||
+6 | Word | IR | ||||||||||||||||||||||||||||||||||
+8 | Word | SR | ||||||||||||||||||||||||||||||||||
+10 | Longword | PC |
Format B
Offset from SP | Size | Value |
---|---|---|
+0 | Word | SR |
+2 | Longword | PC |
Vector list
Vector # | Address | Exception name | Trigger condition | Stack frame |
0 | 000000 | Reset SP | Not really a vector. Used to initialize the stack pointer. | |
1 | 000004 | Reset PC | Reset/startup | |
2 | 000008 | Bus error | Bus cycle couldn't complete properly. | A |
3 | 00000C | Address error | Misaligned (odd) word or longword memory access. | A |
4 | 000010 | Illegal instruction | Tried executing an invalid opcode. | B |
5 | 000014 | Division by zero | DIVUed or DIVSed by zero. | B |
6 | 000018 | CHK instruction | CHK resulted in "out of bounds". | B |
7 | 00001C | TRAPV instruction | TRAPV with overflow flag set. | B |
8 | 000020 | Privilege violation | Use of privileged instruction. Never happens on the NeoGeo since the 68k always runs in supervisor mode. | B |
9 | 000024 | Trace | After each executed instruction when 68k is in trace mode (debugger function). | B |
10 | 000028 | Unimplemented instruction (line A) | Used to implement 680xx instructions in software. Not used on the NeoGeo. | B |
11 | 00002C | Unimplemented instruction (line F) | Used to implement 680xx instructions in software. Not used on the NeoGeo. | B |
12 | 000030 | Reserved/Unused on 68000 | ||
13 | 000034 | |||
14 | 000038 | |||
15 | 00003C | Uninitialized interrupt vector | Default vector used by uninitialized peripherals. | B? |
16 | 000040 | Reserved | ||
17 | 000044 | |||
18 | 000048 | |||
19 | 00004C | |||
20 | 000050 | |||
21 | 000054 | Normally reserved but used on the NeoGeo CD. See 68k interrupts. | ||
22 | 000058 | |||
23 | 00005C | |||
24 | 000060 | Spurious interrupt | No acknowledge from hardware. | |
25 | 000064 | Level 1 interrupt autovector | V-Blank (cart) / Timer interrupt (CD). | |
26 | 000068 | Level 2 interrupt autovector | Timer interrupt (cart) / V-Blank (CD). | |
27 | 00006C | Level 3 interrupt autovector | Cold boot (cart). | |
28 | 000070 | Level 4 interrupt autovector | Not used on the NeoGeo. | |
29 | 000074 | Level 5 interrupt autovector | Not used on the NeoGeo. | |
30 | 000078 | Level 6 interrupt autovector | Not used on the NeoGeo. | |
31 | 00007C | Level 7 interrupt autovector | Not used on the NeoGeo. | |
32 | 000080 | TRAP #0~15 | TRAP instructions. | 2 |
48~63 | 0000C0~0000FC | Reserved/Unused on 68000 | ||
64~255 | 000100~0003FF | User interrupt vectors |
Templates
For cartridge systems
org $0
dc.l $0010F300 ; Initial SP
dc.l $00C00402 ; Initial PC
dc.l $00C00408 ; Bus error
dc.l $00C0040E ; Address error
dc.l $00C0040E ; Illegal Instruction
dc.l $0000034C ; Divide by 0
dc.l $0000034E ; CHK Instruction
dc.l $0000034E ; TRAPV Instruction
dc.l $00C0041A ; Privilege Violation
dc.l $00C00420 ; Trace
dc.l $0000034E,$0000034E ; Emu
dc.l $00C00426,$00C00426,$00C00426 ; Reserved
dc.l $00C0042C ; Uninit. Int. Vector.
dc.l $00C00426,$00C00426,$00C00426,$00C00426 ; Reserved
dc.l $00C00426,$00C00426,$00C00426,$00C00426 ; Reserved
dc.l $00C00432 ; Spurious Interrupt
dc.l VBlank ; Level 1
dc.l IRQ2 ; Level 2
dc.l $00C00426 ; Level 3
dc.l $00C00426,$00C00426,$00C00426,$00C00426 ; Level 4~7
dc.l $0000056E,$0000056E,$0000056E,$0000056E ; Traps...
dc.l $0000056E,$0000056E,$FFFFFFFF,$FFFFFFFF
dc.l $FFFFFFFF,$FFFFFFFF,$FFFFFFFF,$FFFFFFFF
dc.l $FFFFFFFF,$FFFFFFFF,$FFFFFFFF,$FFFFFFFF
dc.l $FFFFFFFF,$FFFFFFFF,$FFFFFFFF,$FFFFFFFF
dc.l $FFFFFFFF,$FFFFFFFF,$FFFFFFFF,$FFFFFFFF
dc.l $FFFFFFFF,$FFFFFFFF,$FFFFFFFF,$FFFFFFFF
dc.l $FFFFFFFF,$FFFFFFFF,$FFFFFFFF,$FFFFFFFF
For CD systems
org $0
dc.l $0010F300,$00C00402,$00C00408,$00C0040E
dc.l $00C00414,$00C00426,$00C00426,$00C00426
dc.l $00C0041A,$00C00420,$00C00426,$00C00426
dc.l $00C00426,$00C00426,$00C00426,$00C0042C
dc.l $00C00522,$00C00528,$00C0052E,$00C00534
dc.l $00C0053A,$00C004F2,$00C004EC,$00C004E6
dc.l $00C004E0, IRQ2, VBlank, IRQ3
dc.l Generic, Generic, Generic, Generic
dc.l Generic, Generic, Generic, Generic
dc.l Generic, Generic, Generic, Generic
dc.l Generic, Generic, Generic, Generic
dc.l Generic, Generic, Generic, Generic
dc.l $00C00426,$00C00426,$00C00426,$00C00426
dc.l $00C00426,$00C00426,$00C00426,$00C00426
dc.l $00C00426,$00C00426,$00C00426,$00C00426
dc.l $00C00426,$00C00426,$00C00426,$00C00426