PLX-SM-AFR support

[Claudman]

Matt,

I have a PLX Wide band with the SM-AFR module and the SM to USB adapter that plugs directly into my laptop. I can monitor the AFR via the PLX logger software 3.0, but it does not work directly with Nistune.

Is there any idea if you will directly support the PLX SM-AFR? My other choice would be to get the A/D converter.

Thanks

[Matt]

Support for that unit hasnt been added yet. I'll have to email them and see if they will release the protocol for it

I can see the data logging is supported with their own software
http://www.plxdevices.com/datalogger.html

minutes later...

Okay made a user account on their forum and seen this

iMFD digital output:
http://www.plxdevices.com/forum/viewtopic.php?t=2176

[Benne]

iMFD digital output:
http://www.plxdevices.com/forum/viewtopic.php?t=2176

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[ar99kid]

hello

any news regarding this ? i have also the same combo and in a few days i will received the nistune board from dealer and don't know how to work this AFR monitoring with nistune.

[Shaun]

+1, I'm installing my kit now.

Matt: If theres anything you need, like some dumps of data from the serial interface, Once I get mine installed and serial cable sorted, I can help out there.

Cheers!
-Shaun

[Matt]

From the forum page:

http://www.plxdevices.com/AppNotes/PLXApp018.pdf

Okay I can add this in but it will take a few weeks before I start. I'm recoding wideband/consult classes in Nistune at the moment and fixing crash bugs (Vista)

The iMFD Digital output is

19200 Baud
8 Data Bits
1 Stop Bit
No parity

Packet format is as follows for the SM-AFR

1) Start bit (0x80)
2) Address bit MSB (0x00) for SM-AFR
3) Address bit LSB (0x00) for SM-AFR
4) Instance (0x00) if only one SM-AFR is connected
5) Data MSB
6) Data LSB
7) Stop bit (0x40)
(Packet set repeats exactly every 100mS)


Interpreting the data bits is as follows.

int datamsb;
int datalsb;
int data;

datamsb = datamsb & 0x3F; //This ignores 2 most significant bits
datalsb = datalsb & 0x3F;

data = (datamsb << 6) | datalsb; //data is the AFR value



when data is 0, AFR is 10 (gasoline) = 0.68 lambda
when data is 255, AFR is 20 (gasoline) = 1.36 lambda
when data is 256 AFR is "lean"
when data is 257 AFR is "Air"

[Shaun]

Thanks Matt...

Appreciate your hard work!

Cheers!
-Shaun

[Matt]

Totally rewriting parts of the code. About half way through atm

[Shaun]

Cheers Matt.. looking forward to the update!

Cheers!
-Shaun

[Matt]

Next update wont have it ... but following one will once I've confirmed all changes are stable and there are no additional bugs introduced

[Shaun]

Cheers Matt,

Thanks for the progress update.

Looking forward to it!

Cheers!
-Shaun

[Howlermonkey]

I was wondering about the newer PLX widebands, specifically the SM-AFR, functionality with nistune since there was functionality with the earlier "R series" wideband controllers.....which are no longer in production.

If not, I guess I can use the SM-AFR output into a DLP IO8 for now if nistune doesn't work with the SM-AFR natively?...........is that correct?

[Matt]

SM-AFR etc with iMFD protocol will be supported in the next release. Final testing was completed last week with a simulator developed here