Which discrete mapper has both CHR and PRG RAM?

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

Moderator: Moderators

User avatar
infiniteneslives
Posts: 2104
Joined: Mon Apr 04, 2011 11:49 am
Location: WhereverIparkIt, USA
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by infiniteneslives »

DSC wrote:I would point out the obvious in that
as we move forward to 'everything on one chip' I see this process fading away fast. Once these chips are gone, they will be gone
forever. I don't see a resurgence going back to this technology any time soon.
What do you mean? The NES's hardware (CPU, PPU, etc?) or cartridges/mappers?

There are already clones, flashcarts, and reproductions of all that available for purchase today. Unless I don't understand what you're referring to, there's already been a resurgence...
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers
DSC
Posts: 19
Joined: Tue Dec 18, 2012 12:59 pm

Re: Which discrete mapper has both CHR and PRG RAM?

Post by DSC »

infiniteneslives wrote:
What do you mean? The NES's hardware (CPU, PPU, etc?) or cartridges/mappers?

There are already clones, flashcarts, and reproductions of all that available for purchase today. Unless I don't understand what you're referring to, there's already been a resurgence...

Resurgence of the ORIGINAL technology! EPROMS are going away forever and will not return. It is already getting hard to find old/new stock of certain sizes. Like 8 track tapes, if you liked them, you better go get them now, going, going gone.....forever. I'm not crying about it, just stating a fact. And while I'm there Nintendo on a chip? 90% there is still 90% if you are a fan, you know and if you don't know now you know. Close counts in horseshoes and hand grenades, not audio. Sorry, pretty picky about that last one. My site btw...
http://www.Ninstrument.com

</end of hijacking thread>
3gengames
Formerly 65024U
Posts: 2284
Joined: Sat Mar 27, 2010 12:57 pm

Re: Which discrete mapper has both CHR and PRG RAM?

Post by 3gengames »

Re highjacking:

They aren't going away. CMOS EPROMS are. But Flash is the new tech and I don't see them going OOP for a while. 2KB sizes and such, yeah, never again. 32KB+ you'll be fine.
User avatar
infiniteneslives
Posts: 2104
Joined: Mon Apr 04, 2011 11:49 am
Location: WhereverIparkIt, USA
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by infiniteneslives »

I get that especially with the Audio, but there are hopes for 100% in the foreseeable future. Clone makers don't care that much, but that doesn't mean someone that did care couldn't to it.

EPROMs disappearing is arguably a good thing just based on bit-rot. Flash is cheaper and better anyways if you can shift way from 32pin DIPs.
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers
DSC
Posts: 19
Joined: Tue Dec 18, 2012 12:59 pm

Re: Which discrete mapper has both CHR and PRG RAM?

Post by DSC »

3gengames wrote:Re highjacking:

They aren't going away. CMOS EPROMS are. But Flash is the new tech and I don't see them going OOP for a while. 2KB sizes and such, yeah, never again. 32KB+ you'll be fine.
Socketed ROM days are numbered. The die plans of most Chinese manufacturers are all going surface mount. Will you be able to find them in 10 years, sure, but at what price. If recent years are any indicator, expect to pay. As the demand goes down for any component, you find the same thing. Look at prices for through hole RF chokes for instance. Ridiculous!
80sFREAK
Posts: 275
Joined: Sat Sep 03, 2011 11:40 pm

Re: Which discrete mapper has both CHR and PRG RAM?

Post by 80sFREAK »

infiniteneslives wrote: There are already clones, flashcarts, and reproductions of all that available for purchase today.
PURCHASE. MUST HAVE!!! HURRY UP!!! BRAND NEW!!! When you or someone else say so, think about this....

Image

Image

Image
tepples
Posts: 22708
Joined: Sun Sep 19, 2004 11:12 pm
Location: NE Indiana, USA (NTSC)
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by tepples »

infiniteneslives wrote:I get that especially with the Audio, but there are hopes for 100% in the foreseeable future. Clone makers don't care that much, but that doesn't mean someone that did care couldn't to it.
To estimate how much one would have to care: How many hundred thousand dollars would it take to go from Verilog on an FPGA to an accurate NOAC ASIC?
User avatar
infiniteneslives
Posts: 2104
Joined: Mon Apr 04, 2011 11:49 am
Location: WhereverIparkIt, USA
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by infiniteneslives »

tepples wrote:
infiniteneslives wrote:I get that especially with the Audio, but there are hopes for 100% in the foreseeable future. Clone makers don't care that much, but that doesn't mean someone that did care couldn't to it.
To estimate how much one would have to care: How many hundred thousand dollars would it take to go from Verilog on an FPGA to an accurate NOAC ASIC?
Doesn't really require much money aside from whatever tools are needed for development. Time is the biggest investment. You just need someone with the skills to be interested in developing it. The trick at that point is to take the necessary (often negelected) step of taking it to market. How does kevtris' APU stack up against the NES's? I'm sure it's next to flawless, or could be if he was motivated to make it so. The gap that's really missing is getting his NOAC to market which has it's own set of hurdles. I suppose that's where the biggest financial hurdle is, taking the little piggy to market. Hard to say what that cost would be exactly, depends greatly on how one were to do it.
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers
User avatar
sonder
Posts: 116
Joined: Wed Jun 26, 2013 12:35 pm
Location: Baltimore
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by sonder »

sonder wrote:
lidnariq wrote:Nestopia does not understand iNES byte 10. Because one of the last 6 bytes were set, it clears all of bytes 7-15, so the part where you're getting PRG-RAM is intrinsic.

Really, use NES 2.0.
thanks, doing that solved it.

Code: Select all

NES_MAPPER=2  ; UNROM

.db $4e,$45,$53,$1a        ; NES,eof
;4
.db 8 ;NES_PRG_BANKS  - 128KB
.db 0 ;NES_CHR_BANKS  - no CHR ROM
.db 3|NES_MAPPER<<4 ;flags 6 - vertical mirroring, battery backed SRAM
.db $08 ; NES 2.0
;8
.db 0
.db 0
.db $07 ;8KB BATTERY BACKED
.db $70 ;8KB CHR RAM NOT BATTERY BACKED
;12
.db 0,0,0,0
Well seems like this didn't work ... my SRAM is coming back all seemingly-random indentical values (usually $FC though) anyone have any idea?
sonder
tepples
Posts: 22708
Joined: Sun Sep 19, 2004 11:12 pm
Location: NE Indiana, USA (NTSC)
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by tepples »

Have you tried clearing the identical values in your NES code and then looking at the resulting .sav in a hex editor?
User avatar
sonder
Posts: 116
Joined: Wed Jun 26, 2013 12:35 pm
Location: Baltimore
Contact:

Re: Which discrete mapper has both CHR and PRG RAM?

Post by sonder »

tepples wrote:Have you tried clearing the identical values in your NES code and then looking at the resulting .sav in a hex editor?
i'm looking at the memory in FCEUX. whenever i pause emulation all the values change in tandem. i'm not using PRGRAM at all in the game yet.
sonder
Post Reply