Search found 45 matches

by Haruka
Sat Jul 20, 2019 9:57 am
Forum: NES Hardware and Flash Equipment
Topic: VRC-VI multicart
Replies: 39
Views: 28089

Re: VRC-VI multicart

Sorry for necro-posting this thread. I'm also trying to make VRC6 multicart. I'm a little confused about the replacement of 32K SRAM since it has no +CE but only a single /CE. How did you use a 74LS32 to create a +CE from other pins? Could you please share your schematic? And there is another questi...
by Haruka
Fri Jul 19, 2019 1:08 am
Forum: Newbie Help Center
Topic: Help with Nametable mirroring of Namco 163
Replies: 4
Views: 3675

Re: Help with Nametable mirroring of Namco 163

So that's the emulator's fault, not mine, right? Phew, that's a relief.
Thank you very much for your help!
by Haruka
Thu Jul 18, 2019 10:15 pm
Forum: Newbie Help Center
Topic: Help with Nametable mirroring of Namco 163
Replies: 4
Views: 3675

Re: Help with Nametable mirroring of Namco 163

Thank you very much lidnariq! I tried your solution. First I added lda #$00 sta $4800 near RST handler, forcing the game write to internal RAM once, making emulator believe this is N163. And then I modified ... ora #$C0 sta $E000 to ... ora #$40 sta $E000 so that E000.7 won't be set, preventing emul...
by Haruka
Thu Jul 18, 2019 7:09 pm
Forum: Newbie Help Center
Topic: Help with Nametable mirroring of Namco 163
Replies: 4
Views: 3675

Help with Nametable mirroring of Namco 163

Hello guys! I'm currently studying Namco 163 for a mapper hack project. But now I'm stucked on the Nametable mirroring. Unlike VRC4/MMC3/Sunsoft5/Bandai FCG and other mappers, which write some value to some specific register to set mirroring, N163 has no such registers. From what I've learned, it se...
by Haruka
Thu Jul 18, 2019 3:28 am
Forum: NES Hardware and Flash Equipment
Topic: Connect AY-3-8910 sound chip to FME-7 board
Replies: 126
Views: 86659

Re: Connect AY-3-8910 sound chip to FME-7 board

krzysiobal wrote:Yep, and 8910.A8=VCC, 8910./A9=GND, 8910.CLK=M2 divided by 2
Thank you krzysiobal! I'll try making my reproduction.
by Haruka
Thu Jul 18, 2019 2:07 am
Forum: NES Hardware and Flash Equipment
Topic: Connect AY-3-8910 sound chip to FME-7 board
Replies: 126
Views: 86659

Re: Connect AY-3-8910 sound chip to FME-7 board

It is CPU, not PRG, as you correctly think. So this is the "not so confusing" circuit, right? 74'139 -----v----- GND-|/1E VCC|-+5V 139./2Y1-|1A /2E|-CPU /ROMSEL 139./2Y1-|1B 2A|-CPU A14 -|/1Y0 2B|-CPU R/W -|/1Y1 /2Y0|- -|/1Y2 /2Y1|-139.1A AY.BDIR-|/1Y3 /2Y2|- GND-|GND /2Y3|- ----------- AY-3-8910 -...
by Haruka
Thu Jul 18, 2019 12:37 am
Forum: NES Hardware and Flash Equipment
Topic: Connect AY-3-8910 sound chip to FME-7 board
Replies: 126
Views: 86659

Re: Connect AY-3-8910 sound chip to FME-7 board

I have a question about the circuit. Why connect PRG A14 and PRG A13 to 74'139 and AY-3-8910, rather than CPU A14 and CPU A13 ? We are trying to decode CPU memory region $C000~$FFFF, not PRG, aren't we? Connecting PRG /CE rather than CPU /ROMSEL to 74'139 is also confusing me. I found that what we a...
by Haruka
Wed May 22, 2019 9:07 pm
Forum: NES Hardware and Flash Equipment
Topic: CoolBaby X7 Pocket Famicom teardown
Replies: 6
Views: 16061

Re: CoolBaby X7 Pocket Famicom teardown

1. Those two 16850 rechargeable batteries that power up everything are connected in parallel. No idea if this is good for their life-time or charging 18650. 3. Audio voltage drop and mixing resistors have non-standard values https://obrazki.elektroda.pl/6295830400_1558309850.png I think this is on ...
by Haruka
Sun May 12, 2019 10:21 pm
Forum: NES Hardware and Flash Equipment
Topic: Placing register at PPU memory for multi-cart, possible?
Replies: 10
Views: 10671

Re: Placing register at PPU memory for multi-cart, possible?

BUT IT DIDN'T WORK! I watched the Q0~Q3 of 74'161 using LEDs to show the status and noticed that: 1. Data latched successfully. 2. Once switched to the selected game, data on Q0~Q3 disappeared immediately(all 0). Then the game crashed. Removed the OR gate and tried again: 1. Data latched successful...
by Haruka
Sun May 12, 2019 7:31 pm
Forum: NES Hardware and Flash Equipment
Topic: Placing register at PPU memory for multi-cart, possible?
Replies: 10
Views: 10671

Re: Placing register at PPU memory for multi-cart, possible?

The signal on /LOAD needs to become valid after the signal on CLK, so I think you have the roles of /PPUWR and PPUA13 reversed. Yes, you are right. PPU A13 and PPU /WR should be swapped on my schematic. I think I'd favor triggering on addresses in the range $3000-$3FFF. If you're only using this th...
by Haruka
Sat May 11, 2019 8:50 am
Forum: NES Hardware and Flash Equipment
Topic: Placing register at PPU memory for multi-cart, possible?
Replies: 10
Views: 10671

Re: Placing register at PPU memory for multi-cart, possible?

Yes, indeed. The NOPs are not nessessary.
by Haruka
Sat May 11, 2019 1:05 am
Forum: NES Hardware and Flash Equipment
Topic: Placing register at PPU memory for multi-cart, possible?
Replies: 10
Views: 10671

Placing register at PPU memory for multi-cart, possible?

I've noticed that all multi-carts place their game switching registers at CPU memory region (usually at $8000~$FFFF, sometimes $6000~7FFF, rarely $4000~$5FFF). But if the games already have registers at these regions, the addresses of the game switching registers have to be intentionally manipulated...
by Haruka
Tue Apr 23, 2019 4:07 am
Forum: NES Hardware and Flash Equipment
Topic: Famiclone Dendy to NTSC help
Replies: 1
Views: 5851

Re: Famiclone Dendy to NTSC help

Tried and success! I'll share with you guys in case someone in need someday.

Similar with UM6561 as I assumed.
Connect the two jumpers as shown in the image. (the two red lines)
Change the 26.601712 MHz crystal to 21.47727 MHz.
Finished and enjoy!
subor-d21-bottom.png
by Haruka
Thu Apr 18, 2019 6:42 am
Forum: NES Hardware and Flash Equipment
Topic: Famiclone Dendy to NTSC help
Replies: 1
Views: 5851

Famiclone Dendy to NTSC help

Hello guys! Recently I got a famiclone named Subor D21. It is PAL 50Hz so the game is slow and not fullscreen. So I want to mod it to NTSC 60Hz. subor-d21-top.png subor-d21-bottom.png Here is the mainboard of the famiclone. As you can see, it is an NOAC with a 26.601712MHz crystal. Silkscreen on the...
by Haruka
Fri Nov 09, 2018 4:28 am
Forum: Newbie Help Center
Topic: [SOLVED]Trying to display all tiles of CHR on screen
Replies: 16
Views: 6771

Re: [SOLVED]Trying to display all tiles of CHR on screen

Note that sprite 0 hits require....a sprite 0 hit. At least one nontransparent pixel from the sprite needs to overlap at least one nontransparent pixel from the background tile. Exactly. That's why I changed the left-most column to white tiles whose index are 1. This makes them non-transparent. Als...