Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Messages - bluefoxicy

Pages: [1]
1
Yes by adding a clock crystal that matches the Game Boy's. A link port can also be added.

Cyclone IV handbook says the EP4CE15E17C8N has 15,048 LEs, 594 Kbit embedded memory, 66 18x18 embedded multipliers, 4 general-purpose PLLs, 20 global clock networks, 8 user I/O banks, and 343 maximum user I/Os in the EP4CE15 series but 256 pins on this version.  As a 1.2V version (not low-power), it has a top clock speed of 166MHz; timing issues will apply, but the Gameboy is 4.194304MHz, and the GBC 8.388608MHz (twice GB).

The FPGA allows M, N, and C counters from 1 to 512.  The PLL multiplies the clock by M/(N*post-scale counter).  I see an A510N, which is a 32.768MHz oscillator.  For GBC, you'd need to multiply by 1/0.256, or 1000/256, so use 125/32.  For Gameboy, use 125/64.  Divide these by 2 for the PPU clock and 4 for the CPU clock (if you need PLLs, just produce the PPU clock in the first place, and divide it by 2 for the CPU clock).  Gameboy Advance clock is twice the GBC clock, but it uses a superscalar ARM processor and implementing that is difficult (and might cause timing issues, requiring slower clock speeds, although the FPGA can probably handle it), plus the FPGA may not have enough LEs.

SD2SNES also has a USB port, so you just need a USB-to-link-cable.

SD2SNES is open-source, so maybe start a kickstarter to pay someone to implement all this stuff.  Should work on SD2SNES Pro but it's going to be as much of a lift as creating an FPGA Gameboy Color.

2
News / Re: EDN8 OS v20-BETA. Large update incoming
« on: November 25, 2019, 10:52 PM »
Hi,
is there any news about the os20 ?

Bump yeah.  Willow doesn't play.

3
EverDrive N8 / Re: List of Compatible Systems for N8
« on: November 17, 2019, 03:39 AM »
Mine freezes repeatedly on the RetroDuo. It's not liking Zelda2 something fierce; crashes on Dragon Warrior 4; and overall just is unstable.

4
EverDrive N8 / Re: Is there an API?
« on: November 09, 2019, 05:56 AM »
Oh cool.  There's a Pro?  I'll have an eye out fro that.

5
EverDrive N8 / Is there an API?
« on: November 09, 2019, 01:27 AM »
Is there an API for the N8 to add additional menu options and tools?

I'd like to add things like auto-IPS or built-in Zelda 2 Randomizer.  While Krikzz might add auto-IPS, I seriously doubt he's going to spend his time cloning Digshake's Z2R.

6
EverDrive N8 / Re: SNES/Megadrive adapter
« on: November 09, 2019, 01:18 AM »
Yeah. Most systems are 5V, with the cartridge running 3.3V.

Many cartridges are using resistors or diodes to clamp voltages in a way that can damage your system.  The Everdrive N8 is pretty decent and the SD2SNES is well-engineered; some cheap 32-in-1 cartridges are using straight resistors.

With a resistor network, you suck power and dissipate some as heat, or shunt it to ground.  In such a design, current still flows.

If you want to, you can instead run a low-power MOSFET and a low-power timer, causing the voltage to pull up if it's below 3.3V (less resistance, draws more current, more load on your system and power supply) or pull down if it's above 3.3V (more resistance, draws less current, less load on the system).  A feedback circuit causes this to self-adjust:  if you put it in a 12V system, the duty cycle cuts back and it draws less current; put it in a 5V system and it draws more current.

That's an extra $8-$12 of parts, though.

Note that the address and data lines on the memory chips have to be matched in hardware anyway.  All of that can be varied, and the adapter cable/card can contain the necessary matching circuitry.  It just might cost an extra $5-$10 (rather than paying $200 for a complete set of $190 of circuitry).

7
EverDrive N8 / Re: SNES/Megadrive adapter
« on: November 07, 2019, 03:27 PM »
Can you specify what reasons? I can't imagine any, and it is possible to make a single card that can connect to any of the various cartridge systems slots if loaded with the correct firmware for the system.  Maybe the Everdrive N8 is designed in a manner that makes that not work, though.

8
Quote from: ikari_01
OTOH Super Gameboy might not be too far out of reach
as it already works in "real life" through the cartridge bus.
There is hope  ::) ::)

Considering the DSP-1 is a 10MHz 65c816 (yes, it's more powerful than the SNES main core itself) and the Gameboy Color is an 8.38MHz Z80, it's logically doable.  Mind you, the SD2SNES Pro is a Cyclone IV now; it's actually powerful enough to implement a hardware SNES.

Best approach would be to load the sprites destined for the Gameboy Color PPU into the SNES PPU, essentially hardware virtualizing the PPU rather than reimplementing and shuffling video.  You can do the same with the NES and Genesis if you really have that kind of programmer time; Gameboy Advance displays too many colors.

9
EverDrive N8 / SNES/Megadrive adapter
« on: November 05, 2019, 01:29 AM »
The N8 has a 72-pin connector. SNES has 62 pins.  Megadrive has 64.

It should be possible to:

  • Ground various pins on short connectors, detect that, and identify that you're on an SNES or Megadrive
  • Load up an SNES or Megadrive firmware if connected (via adapter) to such a console
  • Worst case, detect and then notate who the console is; upon reset, load correct firmware

From what I can tell, the Everdrive N8 and Megadrive Everdrives uses a Cyclone 2; the SNES Everdrive X5 seems to use something else, so possibly not possible there.

SD2SNES is 62-pin native, so you can't slap on an adapter to attach it to NES et al.

Pages: [1]