Search found 22168 matches

by tepples
Wed Apr 14, 2021 6:35 am
Forum: NESemdev
Topic: Testing emulator with nestest - i don't understand part of logs
Replies: 3
Views: 73

Re: Testing emulator with nestest - i don't understand part of logs

Bit 5 (place value $20) and 4 (place value $10) do not exist in CPU register P (status flags). Their value is calculated when the flags are pushed through PHP, BRK, or an interrupt. For the sake of convention, logs from Nintendulator show P with bit 5 set to 1 and bit 4 clear to 0. See also "Status ...
by tepples
Mon Apr 12, 2021 7:14 am
Forum: SNESdev
Topic: About audio in rom bandwidth capabilities, and a external cpu...
Replies: 12
Views: 527

Re: About audio in rom bandwidth capabilities, and a external cpu...

Furthermore the S-CPU can actually transfer data to the SPC700 whenever it wants, frame timing or blanking periods have no relevance here. (Because the interface between the S-CPU and the SPC700 is *very* basic, the tricky part is performing these transfers in an efficient way, especially in the ba...
by tepples
Thu Apr 08, 2021 9:34 am
Forum: SNESdev
Topic: SNES oscilloscope readings?
Replies: 30
Views: 1227

Re: SNES oscilloscope readings?

It might mean that making Visual 5A22 won't be feasible until the layers below metal are exposed and photographed.
by tepples
Tue Apr 06, 2021 11:22 am
Forum: GBDev
Topic: Shitty 2.5D - PoC
Replies: 10
Views: 3963

Re: Shitty 2.5D - PoC

SameBoy indeed passes more behavior tests and has finer-scale emulation of the APU than bgb. However, the debugging tools in SameBoy for Windows and Linux are not quite as detailed as those of bgb.
by tepples
Mon Apr 05, 2021 11:27 am
Forum: SNESdev
Topic: SNES Music Pack 1 by Resistance
Replies: 9
Views: 776

Re: SNES Music Pack 1 by Resistance

Unlike the exact rational PAR of NTSC, the exact PAR of 50 Hz PAL involves some fairly big prime numbers such as 64489. This gives the fraction 2950000:2128137 ≈ 1.3862, and the unwieldiness of this is why I waited so long before establishing a 50 Hz counterpart to my long-running list of dot clock ...
by tepples
Sat Apr 03, 2021 6:23 am
Forum: NES Hardware and Flash Equipment
Topic: [FIXED] Nametable issue
Replies: 9
Views: 579

Re: Help! Nametable issue

Have you enabled NMI? If so, what does your NMI handler look like?
by tepples
Fri Apr 02, 2021 8:25 pm
Forum: NES Hardware and Flash Equipment
Topic: Famicom Network System (aka Famicom Modem) Investigations
Replies: 148
Views: 92272

Re: Famicom Network System (aka Famicom Modem) Investigations

Joe wrote:
Fri Apr 02, 2021 8:06 pm
Ben Boldt wrote:
Fri Apr 02, 2021 4:49 pm
Would you mind editing the wiki with your findings?
I would like to, but I can't figure out how to get access to edit pages.
Identity of "Joe" has been confirmed. Try editing now.
by tepples
Fri Apr 02, 2021 7:58 pm
Forum: phpBB Issues
Topic: Achievement unlocked: human spammers
Replies: 8
Views: 969

Re: Achievement unlocked: human spammers

Like a Reddit shadowban? I see two issues with that. Policy-wise: I seem to remember complaints about Reddit's lack of transparency with respect to helping good faith users who got off to a rough start (or who happen to live in a bad global neighborhood) get out of shadowban jail. Technically: As us...
by tepples
Wed Mar 31, 2021 8:23 pm
Forum: SNESdev
Topic: SNES programming Videos
Replies: 27
Views: 3161

Re: SNES programming Videos

I can hazard a guess: Each scanline has 1364 clocks, with 40 of those used for WRAM refresh, leaving 1324. DMA takes 8 clocks per byte, giving 165.5 bytes per line. Each field has 262 lines, with 1 line of prerender, 224 lines of picture, and (262-224-1) = 37 lines of vblank. 165.5 bytes per line * ...
by tepples
Wed Mar 31, 2021 6:46 pm
Forum: NES Graphics
Topic: Amount of BG tiles used in 8-bit and 16-bit video games
Replies: 7
Views: 875

Re: Amount of BG tiles used in 8-bit and 16-bit video games

Play through the Mall level in Haunted: Halloween '85 (there's a demo in Action 53 Volume 3) and see how many tiles get streamed into CHR RAM.
by tepples
Tue Mar 30, 2021 4:36 pm
Forum: NESemdev
Topic: Visual corruption in Super Mario
Replies: 2
Views: 952

Re: Visual corruption in Super Mario

My first guess is that you're accidentally writing palette writes ($3F00-$3F1F) also to the nametable ($2700-$271F). The PPU has special-case behavior to block writes with address $3F00 through $3FFF from going to video memory. You didn't notice this in other games because these are non-scrolling ga...
by tepples
Sat Mar 27, 2021 5:09 am
Forum: NES Hardware and Flash Equipment
Topic: Famicom AV Mod video filter
Replies: 2
Views: 1432

Re: Famicom AV Mod video filter

Have you tried connecting your modded console to a standard-definition television (SDTV), such as one using a CRT?
by tepples
Wed Mar 24, 2021 8:12 am
Forum: Homebrew Projects
Topic: I come bearing SEO for your cc65/ca65 open source projects
Replies: 17
Views: 22930

Re: I come bearing SEO for your cc65/ca65 open source projects

If you have a Facebook page as the primary public-facing URL for an open source project built with cc65, then a link from cc65's wiki might be able to get your page more search engine juice and thus more views.
by tepples
Tue Mar 23, 2021 8:43 pm
Forum: NESemdev
Topic: RockNES 5.66 -April 9th 2021-
Replies: 16
Views: 6989

Re: RockNES 5.64 -released on October 2nd 2020-

I tried running RockNES 5.65 in Wine 5.0.2 on Ubuntu 20.04. I couldn't get it to accept input. wine RockNES.exe A window showing the main menu (Game, CPU, Video, Misc, Options) appears. The Game menu doesn't respond to a click, and Alt+G on the keyboard doesn't open the Game menu. wine RockNES.exe p...
by tepples
Tue Mar 23, 2021 6:53 am
Forum: NES Hardware and Flash Equipment
Topic: NES RP2A03 Logic Threshold
Replies: 16
Views: 3915

Re: NES RP2A03 Logic Threshold

You can use any resources that describe the original 6502, as the 2A03's reset sequence is unchanged from the authentic MOS 6502. It includes at least these cycles, as I understand it: Two reads from an unknown address, whatever voltages happened to be in the program counter at power up. The CPU ign...