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Diffstat (limited to 'src/devices/cpu/m6502/xavix2000.cpp')
-rw-r--r--src/devices/cpu/m6502/xavix2000.cpp128
1 files changed, 64 insertions, 64 deletions
diff --git a/src/devices/cpu/m6502/xavix2000.cpp b/src/devices/cpu/m6502/xavix2000.cpp
index ab40752b1fe..afbf87fd8c6 100644
--- a/src/devices/cpu/m6502/xavix2000.cpp
+++ b/src/devices/cpu/m6502/xavix2000.cpp
@@ -4,12 +4,12 @@
xavix2000.cpp
- The dies for these are marked
-
- SSD 2000 NEC 85605-621
- and possibly
- SSD 2002 NEC 85054-611 (although this might use even more opcodes and need it's own file)
-
+ The dies for these are marked
+
+ SSD 2000 NEC 85605-621
+ and possibly
+ SSD 2002 NEC 85054-611 (although this might use even more opcodes and need it's own file)
+
6502 with custom opcodes
integrated gfx / sound
@@ -17,64 +17,64 @@
see xavix.cpp for basic notes
- the machines using the '2000' series chips seem to have more extra
- opcodes, so presumably these were only available in those models.
- of note, push x / push y and pull x / pull y
-
- Dirt Rebel MX, which is confirmed as 2000 type however seems to require
- some of the documented but 'undocumented' opcodes on the 6502 to have additonal
- meaning for one specific function on startup
-
- 01BC37: A0 3F ldy #$3f
- 01BC39: B2 ??
- 01BC3A: 1B ??
- 9B ??
- -- outer loop
- 01BC3C: 98 tya
- 01BC3D: 5B (has to be 1 byte?)
- -- inner loop
- 01BC3E: A3 (has to be 1 byte)
- 73 (could be 3 byte?)
- 01BC40: 83 FB presumably fb is the address
- 01BC42: A7 (presumably 1 byte)
- 73 (could be 3 byte?)
- 01BC44: 87 FB presumably fb is the address
- 01BC46: D0 F6 bne $1bc3e
- 01BC48: 88 dey
- 01BC49: 10 F1 bpl $1bc3c
- 01BC4B: 8D FB 00 sta $00fb
- 01BC4E: A3 ??
- 01BC4F: 8D FA 00 sta $00fa
- 01BC52: 07 ??
- --
- 01BC53: D0 03 bne $1bc58
- 01BC55: CE fa 00 dec $00fa
- 01BC58: 80 retf
-
- this is presumably meant to be similar to the function found in Namco
- Nostalgia 2
-
- 09FFD8: A9 3F lda #$3f
- 09FFDA: 85 01 sta $01
- 09FFDC: A0 00 ldy #$00
- 09FFDE: AD FA 00 lda $00fa
- 09FFE1: 71 00 adc ($00), y
- 09FFE3: 8D FA 00 sta $00fa
- 09FFE6: C8 iny
- 09FFE7: AD FB 00 lda $00fb
- 09FFEA: 71 00 adc ($00), y
- 09FFEC: 8D FB 00 sta $00fb
- 09FFEF: C8 iny
- 09FFF0: D0 EC bne $c
- 09FFF2: C6 01 dec $01
- 09FFF4: 10 E8 bpl $9ffde
- 09FFF6: 0D FA 00 ora $00fa
- --
- 09FFF9: D0 03 bne $9fffe
- 09FFFB: CE FA 00 dec $00fa
- 09FFFE: 80 retf
-
-
+ the machines using the '2000' series chips seem to have more extra
+ opcodes, so presumably these were only available in those models.
+ of note, push x / push y and pull x / pull y
+
+ Dirt Rebel MX, which is confirmed as 2000 type however seems to require
+ some of the documented but 'undocumented' opcodes on the 6502 to have additonal
+ meaning for one specific function on startup
+
+ 01BC37: A0 3F ldy #$3f
+ 01BC39: B2 ??
+ 01BC3A: 1B ??
+ 9B ??
+ -- outer loop
+ 01BC3C: 98 tya
+ 01BC3D: 5B (has to be 1 byte?)
+ -- inner loop
+ 01BC3E: A3 (has to be 1 byte)
+ 73 (could be 3 byte?)
+ 01BC40: 83 FB presumably fb is the address
+ 01BC42: A7 (presumably 1 byte)
+ 73 (could be 3 byte?)
+ 01BC44: 87 FB presumably fb is the address
+ 01BC46: D0 F6 bne $1bc3e
+ 01BC48: 88 dey
+ 01BC49: 10 F1 bpl $1bc3c
+ 01BC4B: 8D FB 00 sta $00fb
+ 01BC4E: A3 ??
+ 01BC4F: 8D FA 00 sta $00fa
+ 01BC52: 07 ??
+ --
+ 01BC53: D0 03 bne $1bc58
+ 01BC55: CE fa 00 dec $00fa
+ 01BC58: 80 retf
+
+ this is presumably meant to be similar to the function found in Namco
+ Nostalgia 2
+
+ 09FFD8: A9 3F lda #$3f
+ 09FFDA: 85 01 sta $01
+ 09FFDC: A0 00 ldy #$00
+ 09FFDE: AD FA 00 lda $00fa
+ 09FFE1: 71 00 adc ($00), y
+ 09FFE3: 8D FA 00 sta $00fa
+ 09FFE6: C8 iny
+ 09FFE7: AD FB 00 lda $00fb
+ 09FFEA: 71 00 adc ($00), y
+ 09FFEC: 8D FB 00 sta $00fb
+ 09FFEF: C8 iny
+ 09FFF0: D0 EC bne $c
+ 09FFF2: C6 01 dec $01
+ 09FFF4: 10 E8 bpl $9ffde
+ 09FFF6: 0D FA 00 ora $00fa
+ --
+ 09FFF9: D0 03 bne $9fffe
+ 09FFFB: CE FA 00 dec $00fa
+ 09FFFE: 80 retf
+
+
***************************************************************************/
#include "emu.h"