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Open Source LSU4.9 Wideband Controller
http://forum.diyefi.org/viewtopic.php?f=5&t=2227
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Author:  Fred [ Thu Mar 10, 2016 9:18 am ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

Judging by the look of the components on it, I'd say that he'd be violating the conditions of use of this board by telling you more about it. From that, you can probably guess what it is. If I'm wrong, I apologise in advance. If I'm right, it serves no real use as the firmware is utterly terrible.

Author:  tmbryhn [ Thu Mar 10, 2016 12:21 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

Thank you, Dtm. It's not ment for replacing any stock VAG-ECU - I simply thought I used one of those cases as I had one lying around.

Let's put it this way; irregardless of the firmware of choice (for the moment), doing automotive hardware design that works in the real world continues to give me valuable experience, and for that I'm grateful. Right now I've gotten Bluetooth up and running, but struggling with direct USB connection (no adapter, using internal FTDI chipset), as the voltage levels for distinguishing between 0 and 1 on D+/D- seem to narrow, so noise is a problem. Gotta do more testing there.
If Fred has a thread where USB is discussed, I'm happy to join it :-)

Author:  Fred [ Fri Mar 11, 2016 4:58 am ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

Is there an inverter in your equation? Our designs utilise isolator chipsets to split the USB/serial stuff away from the CPU ground so dirty inverters can be used. Don't think there is a USB thread, feel free to start one, I guess.

Fair enough re learning experiences. It is a good way to achieve that :-)

Fred.

Author:  CarlH [ Sat Apr 09, 2016 10:25 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

I'm noticing something that doesn't make sense to me on the original Hellfire implementation. The firmware calculates the pump current by "V(Ip) - V(2.5)", but the amplifier circuit looks to be referencing the gain to point "Rcal" instead of the 2.5V Vgnd. To implement what I think the intent was:
1 - Insert at 22k in series with the Rcal connection to pin 6 of U1
2 - Connect a 330k from pin 6 of U1 to VGND (pin 14 of U1)

Also, since there is a ~+/-600mV offset when the pump current switches polarities, the IPOUT vs. PWM could made to be more linear by connecting the output of the pump amp (above) to the negative feedback of the pump amp (pin 9 would connect to pin 7 instead of 8). I haven't tried this yet, but might be a worthwhile improvement...

Author:  speedy [ Thu Jul 21, 2016 10:15 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

Hello. I'm following the project for a while and I finally assembled HellFire's design but there is one thing that startles me - everything is working great, heater PID and Nernst PID but I think the pump current is too low, when I connect multimeter in series with red wire of LSU4.9 I see about 2.3mA but the Bosch datasheet says that in free air it should be 2.55mA. I tested it with 2 sensors to be sure. What could be the problem?

Author:  toc [ Fri Jul 22, 2016 9:57 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

The accuracy of your multimeter, or accuracy of resistors chosen?

Author:  speedy [ Fri Jul 22, 2016 11:28 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

I tested it with 2 multimeters, the difference between them is about 0.03mA, which resistor could make this kind of problem when I'm measuring the pump current directly?

Author:  speedy [ Tue Jul 26, 2016 7:02 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

Nobody knows an answer?
Or maybe I shouldn't worry about it and it's good?
I'm little confused because the sensor is keeping nice constant heat voltage and Nernst voltage is 0.45.
If it matters the sensor is from BMW E46 320d Euro 4 version, I bought 2 pieces in case 1 was damaged.

Author:  ender11 [ Sun Aug 27, 2017 6:14 pm ]
Post subject:  Re: Open Source LSU4.9 Wideband Controller

any data about 4-wire denso wbo sensors?

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