All right, I hooked up the VSS straight to the mpguino, and nothing. Tested it with the volt meter and got 4.6something volts. It was hard enough to get the damn thing off the contrast menu, which makes me think it might be voltage dependent or something. I T'd off all three buttons with 10k resistors and soldered them, with no effect; although I left it unplugged overnight, and I think I got three separate button presses out of the thing, but that was it. Then the buttons stopped working.
It's not even reading the Vss, and the buttons act like they're being pressed when I drag my finger across the large amount of extra pins, which makes me wonder if the architecture is that different or not.
When it's in the car, it's getting 12v. I might make a 9v reg and use that to lower the voltage a bit.
Does
NKCelectronics.com: BEST PRICED Arduino boards, Freeduino, IC PCB adapters, Connectors, Pin Headers. FAST GLOBAL SHIPPING sell bad stuff or something? I'm wondering if I might have just gotten a bad device, although I know I can't return it because I soldered it.
I don't think it'll do anything to my ecu, but I also don't think that it needs to be amplified if it's getting so close to 5v at the 'duino.
I'll hook up the Hz meter and see if that could work as my speedometer or something. Who knows, maybe it'll work just fine.
Then again, maybe I'll be making a trip to sears to buy a new meter soon.
UPDATE: Yeah, the car did NOT like not having a resistor in place. My transmission light was freaking out and it kept throwing a check engine code. On another note, my multimeter's Hz setting is only off 10mph when I'm on the freeway. So I get to use that for my speedometer. Still no buttons. I'm gonna ask the people who make the seeeduino if they could post a schematic in .pdf of the seeed mega, and I'll go from there.