Commit Graph

55 Commits

Author SHA1 Message Date
vin
7d148924e2 start implementing PPU 2024-07-21 13:53:04 -04:00
vin
85c6a414f9 fix rest of logging format issues
Now the format perfectly matches nestest.log.
The only mismatch is now at the unimplemented APU memory addresses.
2024-07-20 21:39:04 -04:00
vin
81575946ae fix status flag bug in ASL and ROL 2024-07-20 21:18:11 -04:00
vin
70937cd61f replace tabs with spaces to better match nestest.log 2024-07-20 20:27:55 -04:00
vin
ca5a09cd94 fix warnings and move cpu registers+flags to header 2024-07-07 13:04:16 -04:00
vin
e1cdd73868 implement all of the nestest unofficial opcodes and fix branch cycles 2024-07-04 15:06:15 -04:00
vin
4ccf9f5cee add preliminary implementation of the unofficial opcodes 2024-07-04 14:17:40 -04:00
vin
c4fc40a036 start implementing unofficial opcodes 2024-07-04 12:11:53 -04:00
vin
5cd467eaf6 achieve cycle accuracy for official opcodes
Now, the unofficial opcodes can be implemented, and then the PPU and
APU.
2024-07-04 11:18:38 -04:00
vin
d57acb77c7 finalize trace logging to match nestest.log minus PPU cycles 2024-07-03 21:49:27 -04:00
vin
4fcc8d48f4 improve branching cycle accuracy 2024-07-03 20:40:57 -04:00
vin
2236e79556 fix SBC bug in the rewrite and improve logging 2024-07-03 19:56:36 -04:00
vin
d8bb5a5ccf call opcode function pointer instead of using switch case
Also improve logging.
2024-07-03 19:22:00 -04:00
vin
a4b39966ae start refactoring opcode defs into an array 2024-06-30 19:10:29 -04:00
vin
f28733401e combine macro for updating N and Z status flags 2024-06-30 15:46:25 -04:00
vin
47b8fac273 fix alignment of logging with ABS_X and ZP_X 2024-06-30 15:20:30 -04:00
vin
4525490beb fix indirect JMP bug where the high byte does not increment out of page
https://old.reddit.com/r/EmuDev/comments/15plfes/having_an_issue_with_nestest_on_my_6502_emulator/jvyck7k/

With this, it seems that all official opcodes run as nestest expects.
Now, it's the unofficial opcodes that need to be implemented.
2024-06-30 15:20:03 -04:00
vin
718f89c9c5 fix incorrect argument for INC
Perhaps a refactor is in order for the arguments to the opcodes.
2024-06-30 09:54:05 -04:00
vin
45c2312976 fix incorrect argument for ASL and LSR 2024-06-30 08:58:20 -04:00
vin
99082b5528 fix JSR, RTS, and RTI
JSR was pushing 1 too high PC and RTS was 1 too low
RTI was only pulling the low byte of PC
2024-06-30 07:56:08 -04:00
vin
5535e5de70 change SBC to be ADC with one's complement instead of two's
It seems that is what was expected when run with nestest.
2024-06-30 06:28:41 -04:00
vin
4b7fae0010 fix status flag ordering shenanigans 2024-06-29 09:51:49 -04:00
vin
5d36aeb885 fix ADC bug where V is calculated with new A instead of old A 2024-06-29 09:51:12 -04:00
vin
f16ab6cb6d fix status register to match nestest 2024-06-28 18:15:37 -04:00
vin
3977ab2a5d improve logging and JMP indirect 2024-06-28 18:15:34 -04:00
vin
c1a42045e6 fix more bugs 2024-06-28 10:28:53 -04:00
vin
09692f45f6 fix JSR and RTS bug
The stack's PUSH and PULL weren't proper and JSR was reading wrong
argument it seems.
2024-06-28 10:18:01 -04:00
vin
3ebdeab784 start logging instructions as nestest.log has done 2024-06-28 10:17:37 -04:00
vin
6a5b0b728e start fixing bugs with memory access
So this is why tests should be written while writing the program
and instructions instead of all at once later. If this were all to be
rewritten (which it probably will), I should add tests for each opcode
instead of waiting until the end for ROM loading support.
2024-06-17 15:11:45 +05:30
vin
77d37dd455 implement basic iNES and Mapper 0 ROM loading
It seems like the test ROM loads fine but the instructions are not,
but that's exactly what the test ROM is for I suppose.
2024-06-17 14:46:46 +05:30
vin
1f6e3b054c replace bit comparisons with 0 from greater than to not equal
They're both the same and the compiler might have already optimized it
away. It also conveys the message better in my opinion.
2024-06-16 17:11:51 +05:30
vin
745496ccd1 add memory mirroring for system and ppu memory 2024-06-11 15:38:58 +05:30
vin
44273e69b9 add separate implied/accumulator functions for certain opcodes 2024-06-11 15:08:53 +05:30
vin
a3189d90af add jsr, rti, rts 2024-06-10 23:27:14 +05:30
vin
3412a03a5e implement untested most of stack-related opcodes 2024-06-10 23:27:11 +05:30
vin
dbb952a52b add lsr, rol, ror 2024-06-10 14:33:12 +05:30
vin
ebdf50cdf3 implement tay, txa, tya 2024-06-10 14:28:13 +05:30
vin
454276a50c implement sta, stx, sty 2024-06-10 14:28:13 +05:30
vin
e07d5917a1 implement se?() opcodes and remove extra 65c02 opcodes 2024-06-10 14:28:07 +05:30
vin
23008662ce implement more instructions 2024-06-09 22:50:33 +05:30
vin
68ecbce235 add opcode_mem() function to return memory address and not pre-peek
Of course all of these opcodes need to be tested later...
2024-06-09 22:15:21 +05:30
vin
c417bf2276 add memory writing functions 2024-06-09 16:07:09 +05:30
vin
4db0a8163e implement some more instructions and branching? 2024-06-09 16:02:04 +05:30
vin
858cbfba48 fix potential adc overflow flag bug 2024-06-09 15:35:31 +05:30
vin
76b9059b2e add blank todo opcode functions based on opcode json 2024-06-09 13:11:05 +05:30
vin
207c6903f5 programmatically create switch cases for opcodes based on opcode json
The JSON is from https://github.com/ericTheEchidna/65C02-JSON/ and
saved me a lot of time from writing the cases for each opcode by hand.
2024-06-09 13:08:31 +05:30
vin
72e29b3d25 move addressing mode parsing into separate function 2024-06-08 22:08:51 +05:30
vin
1ac30a026b add adc and actually fix peek/16 2024-06-08 17:41:17 +05:30
vin
bd85b80ba7 fix peek 2024-06-04 17:48:34 +05:30
vin
36a8eefd00 shorten addressing mode enum names 2024-06-04 16:16:48 +05:30