What ohm values should I use for the Resistor Array? Do I even have to use a resistor array? I’m not sure but I don’t think I do. Isn’t a resistor array (network resistor) just a bunch of resistors tied together on one end?
Also, I wanted to make a 6 button pad for Street fighter II’ , but the web page never goes into detail on pin outs or what lines to hook up the 3 ICs to get this all to work. Something about double polling between 2 ICs and using the third to switch between polling both chips.
Looks like this semi conductor is now discontinued and hard to come by. Oh well.
Edit:
I guess I’ll answer my own question. I was able to use 4.7K resistors and did not have to use a network resistor. I guess this is for anybody looking to make a PCB for a PC-Engine.
I found a NTE74**257 IC. Looked at the data sheet and they looked similar enough. I gave it a go and it seems like it is working. I guess I’ll post pictures for anybody who might be interested if I decide to get around to it.
4.7k is a good choice, pretty much anything between that and 100k would be fine, but Im sure you know I use 4.7k-10k for all of my pullups. Yes, you can use individual resistors instead of bussed arrays if you need to. 74XX157’s are still made by the crap ton, like this one: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=MM74HC157N-ND
THe only difference I can see between the 257 and 157 is that when the ‘output enable/strobe’ line is high, the 257 makes the outputs high Z, while the 157 makes them low. I don’t know enough about TG16/PC-E to know if this’d be a problem, but I’d get the 157s just to be sure.
Keep us posted, and if you ever get a chance to monitor things on an o-scope, I’d love to see it, especially with timing information
Thanks Toodles for the link to the IC’s I was having trouble finding those on Digikey. Going to order a few to try to figure out how to make the 6 button variant. May have to disassemble my Duo-RX pad or Avenue 6 and poke and prod it with a multimeter to figure it out.
The 3rd line you typed about high Z flew over my head since I am only an electronics novice.
I’m happy to say that I got it all put together and it is working, so now I can play shooters without getting a sore thumb joint near my palm.
The pull-up resistors are 47K, not 4.7K and even a couple of lines to the cord have them. Other lines to the cord have in-line 330 resistors. The second IC, the switches and the 680 resistors are for the rapidfire circuit which may well be omitted.
Also, bypass caps (which aren’t mentioned in the gamesx scheme) are recommended of course (10u electrolytic, 0.1u ceramic).
A 8+1 SIP resistor array is what I would use if I ever make an adapter myself. A single component for all input lines and I don’t have to buy it online as my local shop carries them.
Hmnnn. Would 4.7k resistors do any damage to anything? As of right now I have it working with 4.7k resistors, and for the Avenue 6 pcb clone, I am going to use the 10k ohm resistors used in a cthulhu. Maybe I should order 47k resistors from Digi-key while I’m at it.
I just took apart my Avenue pad 6, and luckily it looks easy enough to reverse engineer. I’ll be uploading my progress, photos of the PCB, and my Circuits as I get done with it. I hope to make a schematic for the Avenue Pad 6 since nobody has seemed to have done it. Not putting in turbo because the chip, capacitors and Transistor used looks like to add up $10 to the project and more work.
I just recently got SFII’ for my PC Engine, but the Avenue 6 and Duo-RX pads are not to my liking.
Maybe you can help me with the button mapping for the adapter I’m going to build. I don’t have a PC Engine and I can’t remember the button assignment (the fact that the pad has button I on the right and II on the left is confusing).
Taking platform games (e.g. Legend of Hero Tonma) as an example, which button layout is correct?
Hey anyone. I am trying to find a replacement for the Transistor used, he DTC114Y It looks like it is an obsolete item on Digikey. Is there a replacement part I can use for this? Will any transistor do? I think it is an NPN.
Yeah, it looks like any NPN would do. Very low current, and very low speeds so you don’t need anything fancy, just find the cheapest NPN you can. I keep a stack of 2N3904’s for that sort of purpose; if you were going to order some online, I’d grab one of those, otherwise just grab whatever transistors are labelled NPN at radio shack.
Thanks Toodles. Would I not be able to take any NPN transistor and add a 10k resistor to the base and then, solder a a 47k resistor from the base to the emitter? Basically adding the resistors to outside the transistor? I have all of those on hand.
Finally I have an Avenue 6 PCB done. I first went with the No rapid fire diagram, but it did not seem to work in 6 button mode only 2 button.
I went with the diagram that used the turbo chip IC and put in the switch for 6 button and 2 button. If I wanted to add turbo it would only be a matter of buying 6 spdt switches, but since I don’t really need them I didn’t bother.
Just got done play Street Fighter II Dash on the PC-Engine. Just almost beat the game without out continuing on 8 stars, but lost to Dictator a because I’m not used to his AI for this game.
So here is my spaghetti mess of wires. Took so long to trouble shoot when I initially messed up the wiring.
PCB
