I've been using nestest.nes quite frequently and discovered that my emulator behaved wierd when using the (indirect),y test.
I traced the code and found the problem, nestest actually jumps to a wierd address that causes my emulator to go crazy, look at the code below:
It's the JMP that causes the problem, but as you can see, $300 is written too twice (see below) and "corrupts" the address that is being jumped to.
Anyone knows why nestest does this? I've removed some "uninteresting" parts of the code that wasn't affecting the JMP....
0000DB7E: A9 00 lda #$00
0000DB80: 8D FF 02 sta $02FF
0000DB83: A9 01 lda #$01
0000DB85: 8D 00 03 sta $0300
----
0000DB9C: A9 A9 lda #$A9
0000DB9E: 8D 00 03 sta $0300
---
0000DBAB: 20 B5 DB jsr $DBB5
--
0000DBB4: 60 rts
--
0000DBB5: 6C FF 02 jmp ($02FF)
---
I traced the code and found the problem, nestest actually jumps to a wierd address that causes my emulator to go crazy, look at the code below:
It's the JMP that causes the problem, but as you can see, $300 is written too twice (see below) and "corrupts" the address that is being jumped to.
Anyone knows why nestest does this? I've removed some "uninteresting" parts of the code that wasn't affecting the JMP....
0000DB7E: A9 00 lda #$00
0000DB80: 8D FF 02 sta $02FF
0000DB83: A9 01 lda #$01
0000DB85: 8D 00 03 sta $0300
----
0000DB9C: A9 A9 lda #$A9
0000DB9E: 8D 00 03 sta $0300
---
0000DBAB: 20 B5 DB jsr $DBB5
--
0000DBB4: 60 rts
--
0000DBB5: 6C FF 02 jmp ($02FF)
---