14point7 SLC OEM - budget wb02 controller

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festy
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Re: 14point7 SLC OEM - budget wb02 controller

Post by festy »

antus: user error maybe? :mrgreen: Assume you're running the latest firmware and NAW_7S Edit versions?
I just had a look at the NAW_7S forum on the 14point7 site, they look pretty flexable in what you can configure, compared to the SLC OEM where you can't really change anything apart from the calibration settings.

The SLC OEM has two jumpers for it's calibration - the first is a hardware calibration (performed without the sensor connected) that sets the board's calibration value based on an internal voltage reference reading, the second jumper is for free air calibration of the sensor.
The hardware calibration only needs to be performed once after building the EvK (best to do it after the controller has been running for 30 minutes so the components are up to their normal operating temperature) or if you replace key components on the board you'll need to re-calibrate then too.
The free air calibration requires the sensor to be removed from the exhaust, which I guess would be the same for any WB free air calibration.
The procedure for both calibrations is pretty simple with the OEM EvK - from memory you just power the unit up with the relevent jumper in place (only 1 calibration at a time obviously), wait 5 seconds, measure the voltage on the linear output pin (go/no go thresholds are in the instructions) then remove the jumper and reboot.
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charlay86
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Re: 14point7 SLC OEM - budget wb02 controller

Post by charlay86 »

I have been meaning to spy on the NAW7s serial port to see what commands do what, so I can make a tunerpro aquisition definition to control it.
it should be simple enough to log it, I seem to recall reading some stuff on the forums describing the command to send, the data it would return and how to convert it to lambda.
PC sends "7" to NAW_7S to request 1 packet.

Each packet consists of:

Byte 0-3: IEEE formatted 32 bit floating number representing the free air calibrated pump current
Byte 4-7: IEEE formatted 32 bit floating number representing the uncalibrated pump current
Byte 8: 8 bit number representing sensor temperature free air

Once you get the pump current you have to convert that to lambda:
if (Pump_Current>128) //lean
{

Temp_Double=-0.00000359*Pump_Current*Pump_Current+0.003894*Pump_Current-0.4398; //O2 conc
if (Temp_Double>0.209)
{
Temp_Double=0.209;
}
Lambda = (Temp_Double/3+1)/(1-4.76*Temp_Double);
}
else //rich
{
Lambda=0.00003453*Pump_Current*Pump_Current-0.00159*Pump_Current+0.6368;
}


The conversion of Byte 8 to temperature in % is:
Temperature = 1500 / (Byte 8)
would be nice to be able to log the PCM and wideband simultaneously
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antus
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Re: 14point7 SLC OEM - budget wb02 controller

Post by antus »

my problem was the device wouldnt connect via usb when i plugged it in. i tried multiple cables and checked the cable wasnt catching on the case, and no go. eventually (after many attemps and on the 2nd session of trying) it did with the same laptop and original usb cable. So i dont know. Its the firmware the device shipped with and current at the time drivers. now i know its 0-5v for AFRs 10-20 and i log via the delco its pleanty usable and ive not tried to connect to the pc again. now ive mentioned it to be fair i suppose i should do some more testing and on another pc.
Have you read the FAQ? For lots of information and links to significant threads see here: http://pcmhacking.net/forums/viewtopic.php?f=7&t=1396
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festy
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Re: 14point7 SLC OEM - budget wb02 controller

Post by festy »

Might just need to update the PC software? http://14point7.com/forum/index.php?topic=639.0
-USB will work first time it is connected
-Ability to change the refresh rate of the 7 Segment display.

No firmware update is required, this is strictly a PC software update.
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festy
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Re: 14point7 SLC OEM - budget wb02 controller

Post by festy »

Well I've had the SLC OEM wired in for a while now, and must say I'm 100% happy with it so far.
I don't know if the few seconds of heating it gets while the fuel pump primes before start has any impact on how quickly it becomes ready, but the logged AFR readings settle within about 20 seconds after starting the engine.
I haven't really had the opportunity to give the simulated NB output much of a test yet though - my AFRs are still incredibly low everywhere so no hope of getting any cross counts until I get working on the tune... but the WB is permanently installed so I don't really have much need for the simulated NB anyway.
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Holden202T
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Re: 14point7 SLC OEM - budget wb02 controller

Post by Holden202T »

the heating period sounds pretty normal!

do what i do in the gemini, wb ve learn :D i have a run at the drags then it tunes the part throttle for me on the return road back to the pits :) and just disable the narrowband in the tune!
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