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Old 06-19-2008, 01:04 PM   #9 (permalink)
OBDuino coder
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Join Date: Jun 2008
Location: Montréal, QC
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Titine - '13 Hyundai Sonata Hybrid
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Ok it seems we do not need a "jeff interface" or transistors to connect the K line to the TX/RX of the chip, a single Motorola/Freescale chip already exist that does everything: the MCZ33290EF
The MC33290 is a serial link bus interface device designed to provide bi–directional half–duplex communication interfacing in automotive diagnostic applications. It is designed to interface between the vehicle’s on–board microcontroller and systems off–board the vehicle via the special ISO K line. The MC33290 is designed to meet the “Diagnostic Systems ISO9141” specification.
It's the chip used in the Blafusel "KL interface serial cable" and also a obd2-lcd device.

To use it, it's very easy, PD0 and PD1 are direct connect to the Atmel chip:

(picture of their PDF available at

So I tried to get one here in Montréal but can not find one, it's a $1.46 chip but as a special order they want to charge me $8 for it, WTF indeed!

If someone bought some at digikey or your local electronics parts store, I will be glad to paypal you $2 to ship one to me in a standard envelop
2013 Hyundai Sonata Hybrid
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