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Old 10-23-2008, 10:28 AM   #231 (permalink)
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Join Date: Jun 2008
Location: Montréal, QC
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Titine - '13 Hyundai Sonata Hybrid
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Originally Posted by dcb View Post
You might want to bump up c1 to about 330uf or more to help prevent brownouts while cranking. Or draw it in context with the existing power supply.
I am not using this power supply schematic, I am using the +5 from the Arduino. This schematic is useful if you want to make a "true" ELM327 interface that will be plugged on a laptop for instance. The RS232 parts is not useful for us too as we plug directly the tx/rx on the rx/tx of the Arduino in a direct connect mode. As for power, the RS232 parts is useful only if you want to connect the ELM327 to a laptop.

Originally Posted by dcb View Post
Lose the rs232 circuit all together and voltage monitor, there is probably a pid for system voltage, no?
There is no PID for voltage, so I take it from the ELM327, it's just a voltage divider that costs 15¢ to do and you retrieve the value with a ATRV command to the ELM, it's nice

About the possibility to connect the ELM327 to a laptop, I think I can do something. First I have to stop the application on the Arduino so it will stop sending thing on the serial port. Then I put an inverter switch on the tx/rx for them to become rx/tx so the ELM327 will use the MAX232 of the Arduino and I will just have to plug a cable between the laptop and the Arduino to talk directly to the ELM327. I will have to test first, it's just an idea, but it should work.

Originally Posted by dcb View Post
I definitely like the color coding
You welcome

I am re-doing a proto with CAN/ISO, in a more standard way (point to point wire)

2013 Hyundai Sonata Hybrid
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