Turbografx-16 & PC-Engine Reproduction Hucards & Cases Now for Sale!!!!

[TheOldMan]

IMHO, you should only need a fairly simple FPGA/CPLD to do the Arcade Card ... your problem is more going to be in the number of I/O pins that you need, and the total number of individual IC chips ... trying to fit a CPLD, ROM, and 2 RAM chips into the space that you've got is going to be ... interesting.

I agreee. But there's room for 2 memory chips (Ram or Rom) underneath the board; then you have the
whole top area for the FPGA/CPLD and a memory chip. Which actually might be doable. (Though I think you would need a multi-layer board to do it.)

Ss far as CPLD/FPGA/RAM choices, well you don't have that many anymore if you're talking about using 5V parts...

Always a problem with older systems, unfortunately.

Is the Arcade Card Pro really that rare that it's worth going to all that trouble?

Probably not. It's a Nice design problem, though.

Errr ... don't we already have that "super" Arcade Card with the Turbo Everdrive 2?

Not that I am aware of. Doesn't the arcade card have extra registers? (I'm pretty sure there is at least a shift register available.) Are those emulated on the TED 2?
Extra memory is nice, even if it's single-byte access via a register. Shift register would be nicer, making multiplies and  a few other calculations easier/faster.

[NightWolve]

Yeah, krik voiced the possibility of adding Arcade Card support at the last minute but he abandoned it with his TE v2 redesign unfortunately. Bonknuts got what he wanted though as far as extra writeable RAM per what elmer mentions, you just can't turn that into support for official ACD games from my understanding because the mapper wasn't implemented and whatever else is lacking. That's why it's worth exploring for steve-o/turbo to make a repro of it.

[thesteve]

as far as 5V it wouldnt be required on the cpld as the RAM can be 5V and drive the outputs
a 3.3v chip can address a 5V chip fine

[TheOldMan]

as far as 5V it wouldnt be required on the cpld as the RAM can be 5V and drive the outputs
a 3.3v chip can address a 5V chip fine

+1 problem solved.

[elmer]

as far as 5V it wouldnt be required on the cpld as the RAM can be 5V and drive the outputs
a 3.3v chip can address a 5V chip fine

+1 problem solved.

IIRC, maybe not according to the TailChao's posts specifically complaining about people doing that ... they're around here somewhere.

But perhaps you're thinking about something else, or perhaps I'm just wrong ... I remember just enough electronics to think that I still know something, but I probably don't.

[thesteve]

inputs to the 3.3v chip will need a resistor to limit current, allowing the internal diodes to clamp the voltage
3.3V outputs are sufficient to control TTL 5V inputs, tho not by a large margin

[elmer]

It's entirely up to you, and the implications of the exact details are bit above my knowledge-level, but in my ignorance, it sounds like you're proposing exactly what TailChao was warning against ...

https://www.pcenginefx.com/forums/index.php?topic=18629.msg431983#msg431983

I've seen 3.3V parts on 5V consoles without proper level shifting and ghetto ass diode regulators to drop the supply voltage for them. This is not cool for the parts, the console, or you. But it's done again and again because it's cheap.

He includes a link to the following thread ...

Interfacing CMOS 3.3V logic
http://gendev.spritesmind.net/forum/viewtopic.php?f=13&t=2170

Anyway ... 5V CPLDs do still exist, they're just getting harder to find.

<EDIT>

For example,

http://www.atmel.com/products/programmable-logic/spld-cpld/cpld-atf15xx-family-industry-standard-compatible.aspx

[thesteve]

not quite as he described (hadnt even talked about power source)
i was actually referring to a common exception in most chip data sheets, that states the input voltage doesnt need to be observed as long as currents are
note this only applies to diode protected inputs and would need to be confirmed with the MFG data before designing around it

[TheOldMan]

Okay, problem not solved.

I doubt there would be enough room for the diodes/resistors needed.
You -might- be able to squeeze a level-shifter on there, if it's small. Would we need 2? (input+output?)
Any idea of what kind of delay would that cause...?

Assuming we can't find a stash of big enough 5V CPLD/PGA's somewhere...

[SplatterTrigger]

Do these come with repro manuals, or is that one you just already had?

Only Magical Chase did.

[Sapicco]

Are these available yet?   And, can you make cd games on the hu's?

Sorry to ask again, but were these questions answered somewhere in these nine pages?

[Necromancer]

No, CDs can't go on Hueys.

[elmer]

Not that I am aware of. Doesn't the arcade card have extra registers? (I'm pretty sure there is at least a shift register available.) Are those emulated on the TED 2?
Extra memory is nice, even if it's single-byte access via a register. Shift register would be nicer, making multiplies and  a few other calculations easier/faster.

Nope, you're right, the TED2 doesn't have the Arcade Card's shift-registers.

I guess it's all a question of how you define "Super Arcade Card". If you want 100%-compatibility with the existing Arcade Card, then you'll have to design your own, or wait for some mythical future TED3.

i was actually referring to a common exception in most chip data sheets, that states the input voltage doesnt need to be observed as long as currents are
note this only applies to diode protected inputs and would need to be confirmed with the MFG data before designing around it.

Ah, thanks!

Yes, those discussions specifically mention that some 3.3V chips are designed to accept connection to 5V inputs through a resistor, as documented in the MFG data sheet. The old Cyclone2 FPGA was specifically mentioned.

Okay, problem not solved.

I doubt there would be enough room for the diodes/resistors needed.
You -might- be able to squeeze a level-shifter on there, if it's small. Would we need 2? (input+output?)
Any idea of what kind of delay would that cause...?

Assuming we can't find a stash of big enough 5V CPLD/PGA's somewhere...

They're around, but the prices seem a little high (to me) for the capability that they offer.

A TQFP100 package is going to eat up a lot of board space for only 128 macrocells, and the smaller TQFP44 only offers 64 macrocells. I'm not sure what you'd need in order to replicate the Arcade Card.

In comparison ... the FPGA in Krikzz's TED2 has 1280 cells.

You're also going to be limited by the RAM choices, or you'll end up with lots of RAM chips on your board.

I could only find one MFG of 2MB 5V SRAM chips when I looked, and they seemed quite expensive.

When you start looking for parts that are actually available, you can quickly understand why Krikzz decided to use all 3.3V logic, and add 5V level-shifters.

You only have to look at the TED2 board to see how much physical space that all took up, and that was using a physically-tiny-but-tall 4MB BGA RAM chip, which wouldn't be an option for you if you want the nice plastic case.

[turbokon]

Our black and gold hucards are here.  These will be available mid June or so.

Here are some pictures of a 2 in 1 black card with the built-in switch.

[esteban]

Holy mother of shite!

Gorgeous.