drzaiusx11

My guess is they're going with an ohm meter like design (http://www.circuitbasics.com/arduino-ohm-meter/) where they're using the 1M resistor as the "known" resistor and the pot from the paddle is what you're solving for. They probably put the other paddle output into a high impedance state so it won't mess up the reading since the two paddles share pin 7, then swap. Going with the resistor + cap charger circuit would work too (and be just like the real atari), but would require 2 more caps and also messing with interrupts.

I just ordered a bunch of card connectors for making kits, so yes! The estimated shipping dates are early next month though... (yay china)

Finally got around to making a VCS library that works on both Raspberry PI and Arduino: https://github.com/drzaiusx11/WiringVCS Currently works on 2K, 4K, E0, E7, F4, F6, F8, FA and FE carts. It should be fairly easy to make a ROM dumper from anything arduino or rpi-compatible :-)

Who's Blinky and what's his design? I assume without any external chips you can just wire the io pins directly to a card edge connector. As for line delay, I arbitrarily chose the recommended time delay from an old EEPROM datasheet I found from the early 80s--I may be able to get away with a similarly short time, but most ROMs dump in under a second with my current value so I didn't feel like risking anything shorter for now. The arduino and wiringPI APIs may add some overhead when setting the IO pins that may make adding delays superfluous, but without a decent scope I can't easily check.

Yeah, the official ardiuno products are pretty pricey, but I don't mind supporting the team behind them so I usually end up just paying the "arduino tax" for my stuff. Pretty cool you can get a mega for that cheap nowadays--googling around shows you can get a knockoff of pretty much any arduino product for under $10 USD which is pretty sweet. Its amazing what you can get for your money on bangood and aliexpress these days. I guess its a great time to be a hardware enthusiast. Price wise I'm investigating the new $5 pi for my project. I've tested it on the A+ and B+ so far, but there's no reason it shouldn't work on the new board too since it has the same pinouts and ARM chip. The damn things are pretty much sold out everywhere though, so it may take a while to get my hands on some. The A+ isn't a bad deal at $19 though. At some point I may put up my arduino shield schematics in case someone with an UNO wants to give it a go--do you plan to publish your sketch as open source? With a bit of fiddling I bet I could get your code working on my UNO (I don't own a Mega atm)

If you want to take your costs down even more an arduino UNO retails for $25 while the mega is $45 (USD.) I assume you're making a PCB shield as well, so the added costs of 2 shift registers would be under a $1 (they go for around $0.30 to $0.50 each), so that could shave off about $20 off your current design. I can share my sketch that handles treating the shift registers as extra IO pins too

Cool! My dumper started out as an arduino uno with a couple of shift registers to get the io ports needed. That's why I'm using the wiringpi library, so I didn't have to rewrite my code when I switched to the PI I could refactor out the pi specific parts of my dumper and make a tiny shared lib with detect and dump routines if there's any interest in combining efforts. I'm down for at least taking a look at what you've done so far.

Thanks for the heads up, I'll try your simplified method with my board later this week. PS. Are you working on a dumper as well?

UPDATE: boards are in and work great! I found a few more bugs in my dumper software though, so I'll be updating that soon. So far all my carts work with the exceptions of River Raid II and Pitfall II, but I'm fairly certain those issues are software related and not the actual hardware. Here's an assembled unit: I'm currently toying with the idea of adding colecovision and possibly intellivision ports to the board as well. Looking at the cart pinouts, colecovision should be dead simple since there isn't any bankswitching--the intv's pinouts seem a bit more complicated though (and I have less intv carts to test.) I still need to design an enclosure as well...

So I finally got around to exporting the schematics / layout files. I've also moved the joystick ports / switches to an expansion board that will attach via the JP3 port (controlled by a $0.99 PIC microcontroller) However, the controller port board is still WIP. I finally ordered a new set of boards today, so in the coming weeks I should have something to send out for testing. PS Awesome mini arcade cabinet!

In this topic I made a spreadsheet that may help: http://atariage.com/forums/topic/198194-which-mappers-used-by-which-games/

I know this is an old topic, but after struggling with finding a decent list of games to mapper types I went ahead with stephena's advice and made a script using the output "stella -rominfo" to make my own: https://docs.google.com/spreadsheets/d/10fHcUtS7Z4sIaK9OfbgSLm9z_gj8Rw7xbe3AoBiUA74

Hey Startdust4Ever, no problem! Once I get the boards in after my latest revisions I can send you one at cost to play around with if you want. You can wait till it's "done"--However, I'm fairly certain the hardware for dumping is pretty solid at this point. Here's the items next on my todo list - vcs compatible joystick ports - difficulty switches - tv type switches - reset button - acrylic laser cut case If you only want the final product and just use it for dumping, I'll make sure the board can be populated with just the hardware needed for dumping and nothing else (to keep costs down)

I just received my harmony cart! Stardust4ever, thanks for the tip on development mode; I got it up and running with my dumper in less than 5 mins. Works great! Now I just need to test every rom for compatibility...

Just put the ROM mapper auto detection and dumping code up on github: https://github.com/drzaiusx11/pitari The board plans and Raspberry Pi SD card image will come next, but for now if someone is interested its fairly easy to figure out the wiring by looking at my address and data assignments in the code. Just don't hook the data lines from the carts directly to the RPI since it needs to go through a buffer to convert from 5v -> 3v (otherwise you'll fry your pi.)