I'm thinking about building my own NES via an NES on a Chip..
Any suggestions?
Unless it's portable I don't see the point. The NES-on-a-Chip isn't 100% compatible. Lots of things just seem to be off. Use a real NES or Famicom for anything serious. Use NES-on-a-Chip if its free. If you have a whole NoaC system, use it for a doorstop.
I played some stuff on a NoaC device before and I have to say it sucked. While I could see the games going and they are awesome games everything has this shitty quality to it. You're better off using a dusty NES with a shitty connector. Just my opinion, the NoaC sucks. Wish someone would make a decent one.
MottZilla wrote:
Unless it's portable I don't see the point. The NES-on-a-Chip isn't 100% compatible. Lots of things just seem to be off. Use a real NES or Famicom for anything serious. Use NES-on-a-Chip if its free. If you have a whole NoaC system, use it for a doorstop.
I played some stuff on a NoaC device before and I have to say it sucked. While I could see the games going and they are awesome games everything has this shitty quality to it. You're better off using a dusty NES with a shitty connector. Just my opinion, the NoaC sucks. Wish someone would make a decent one.
i just want to build it for kicks... I have a real NES (with a disabled 10NES) that I use mainly..
I just want to build one for the heck of it really, like practice, etc.. And to just say that I put together an NES from scratch, with the NOAC..
wouln't that be a little too...easy? All you'd do would be soldering a few connections...
If you want to do something REALLY interesting, make a portable out of it. The Benheck.com forums has plenty of info on doing so.
Or... design your own NOAC. Now that is fun and a challenge!
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Or... design your own NOAC. Now that is fun and a challenge!
You mean like code the PPU in verilog for an FPGA?
There are open source 6502 cores, I believe.
ok, i'll make a portable.. it'll probably look like crap though.. it'll be a portable with TV capabilities (on the console itself, and to show game graphics on a TV screen)...
Do NOAC's support 2nd controllers?
evildragon wrote:
Do NOAC's support 2nd controllers?
At least the ones used in mall-kiosk famiclones do. However, they might not be standard NES compatible serial controllers; instead, they might be controllers following a variant of the Atari 2600 input protocol, such as Sega Genesis compatible controllers.
drk421 wrote:
Quote:
Or... design your own NOAC. Now that is fun and a challenge!
You mean like code the PPU in verilog for an FPGA?
There are open source 6502 cores, I believe.
Well, if anybody feels up to it, they could certainly do better than the NOACs in use.
Even with 6502 CPU, a 2A03 I/O block, and a 2C02 PPU on an FPGA, how would you cheaply translate between the 5.0 V of NES Game Paks and the 3.3 V of FPGAs? PowerPak does this with a bunch of level shifters, but that's expensive. Kevin Horton's solution was to put the equivalent of a PowerPak on the same logic board, so that the entire system runs at 3.3 V, but then it can't take carts.
i could use a DC-DC converter.. or use a 12v DC adapter and use two voltage regulators..
(oh yea, that's not for portables btw..)
Um, I've heard that some 5v ROMs actually work ok with 3.3v... Has anyone just tried?
The Powerpak's FPGA is 5V tolerant so it directly takes NES levels on it's inputs, and for outputs, it uses external pull up resistors + internal tristates to get 5V output. Clever but unfortunately the Spartan 2 is one of the last FPGAs with 5V tolerance. Since most of the signals on the cart connector aren't bidirectional though, passive solutions can be used like the same tristate+pull up for outputs and a resistor voltage divider (or better yet cheap buffer ICs) for inputs. A bidirectional buffer like the 74245 might work for bidirectional ports depending on whether NES will take 3.3V as a logical high.
Probably the hardest or most expensive hardware part to get is the 21.47727 MHz clock. 21.48MHz oscillators and even crystals are very rare. Most FPGAs now have PLLs though so maybe some FPGA can use a common colorburst crystal + the PLL.
I still haven't been able to find a NOAC yet. I know it's a simple thing, but I just want to experiment with them.
I do have a device that has an NOAC in it, with native stereo output too.. (it's a dance mat thing).. But I can't take it apart, it's my sisters :p