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Old 08-17-2008, 02:59 PM   #123 (permalink)
Test Tool Engr.
Join Date: Aug 2008
Location: Elgin, IL, USA
Posts: 47

Red Rocket - '02 Honda Civic LX Sedan
90 day: 33.57 mpg (US)

Bronze Bucket - '98 Toyota Corolla VE
90 day: 34.97 mpg (US)

Silver Bullet - '06 Hyundai Sonata GL
90 day: 31.58 mpg (US)
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Well, I think I want in on this project too. I'll be ordering my parts ASAP
I've got an '02 Civic (ISO), and I'll start looking over the code and see what I can see based on the protocol specs I have...

Any suggestions on specific Arduino kits?

EDIT: I got this one -- hope it works out.

EDIT #2 (Sorry, just hate to double-post): I'm looking at the code in the repo, and I think I know why serial won't work. It looks like you're not using the Atmel's native serial port communications. You should be able to just set up the UART to 10400 baud and then rock and roll after sending your 5-baud 0x33 by hand. My understanding is that you don't get a response to 0x33, you get a response to an initialization message that goes out at 10400 baud. (If you guys have gotten past this point, then sorry -- it looks like the code is waiting for a VERY approximate 10400 baud, which will realistically be incredibly off, since the difference between 10400 and 9600 baud or worse is only a couple microseconds (just a handful of ticks).

In other words, you NEED to use the hardware UART block, or you will surely fail at sending an intelligible message (I don't think the 5 baud one is quite as sensitive). Trust me, I've tried doing stuff like this in software using an AT91 at 49MHz, and it didn't work out there, and that has a much finer control. I can't remember the polarity of a 1 or 0 in RS232, but if it's the opposite, you can always just XOR the byte with 0xFF to negate each bit and then send it across. Anyway, once I get my Arduino setup, I'll throw it together and see what I see as well.

Last edited by ishiyakazuo; 08-17-2008 at 10:53 PM.. Reason: Adding some notes/detail, don't want to double-post
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