PLX SM-AFR Serial upgrade

Base on what I see and what little I know, I would lean toward the Innovative system vs PLX Devices. The PLX SM-AFR as an example, needs to to modified to add a DB9 to work with V2 while I believe the LM-1 is already setup with a serial port and would only need a cable. I understand the LC-1 will also work easily but I am not sure what is needed for the LC-1.

http://forum.efilive.com/showpost.ph...1&postcount=60
http://forum.efilive.com/showpost.ph...7&postcount=10
http://sodoityourself.com/max232-ser...vel-converter/
http://forum.efilive.com/showthread....ghlight=serial
http://forum.efilive.com/showthread....ghlight=serial

Quote:

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Originally Posted by Wolfie

Welllp....
I finally received the CORRECT serial converter!
Mounted it from outside the rear case plate,
It took me awhile to figure out the +3.3v tap as the picture was
not clear to me. I was not sure just which place to tap it, but
with the help of my trusty dvm, I got it right.
I didn't have a null modem adapter, so I just cut the end off of
a db9 m/f cable and crimped on a RJ12.
Works nice!!!!!!

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Pics?

What serial converter did you end up with?

Thanks for the WBO2 links, Ill probably end up with a LC-1 as I dont need a guage. :)

Quote:

---

Originally Posted by Wolfie

Welllp....
I finally received the CORRECT serial converter!
Mounted it from outside the rear case plate,
It took me awhile to figure out the +3.3v tap as the picture was
not clear to me. I was not sure just which place to tap it, but
with the help of my trusty dvm, I got it right.
I didn't have a null modem adapter, so I just cut the end off of
a db9 m/f cable and crimped on a RJ12.
Works nice!!!!!!

---

Well done mate. Once you go serial you cant go back to analog! :D

Jez

Does the serial cable that comes with the V2 already have the board interanly in it???

Meaning I can fit a male plug of the back of a Pc to the plx box???

Why is it necessary to do this instead of just putting a stereo minijack Y splitter on the TX plug?

All I see are connections to +V, G, and Tx. All of those are carried by the standard serial cable.

I am not an electronics engineer, but this is what I've been told...

The PLX device does not provide an RS232 serial input and output compatible voltage level. The PLX exposes the internal, unbuffered, unprotected serial TX/RX pins from the CPU. Those TX/RX pins operate at 5V (maybe 3V - I' don't know I haven't looked).

Serial data that is RS232 compliant sends/transmits using 12V signals. You don't want to plug a 12V signal (i.e. a PC or FlashScan) into an unprotected device that expects only 5V (i.e. PLX).

You need to perform a voltage conversion (and possibly a voltage inversion as well) using a MAX232 chip or similar.

Regards
Paul

Ok, that explains the voltage chip on the RS232 connector, but not why it's necessary to open up the PLX box and solder new wires in there.

Ok here's what I found on the stereo minijack plug that carries the PLX serial data, for anyone that cares.

Tip carries +3.3v
Middle carries the serial data
Base is the ground.

**edit*** - this is incorrect


So what I'm thinking is that I can put a regular headphone jack Y splitter on there, use one to transmit to the gauge, and use the other to transmit to EFILive.

The EFILive one would have to go through the voltage regulator chip as listed above, from my understanding.

okay SO.... If i had a little case.. which i do... and grabed my multi meter.. i could work out the 3 out pins of the RS232 and simply remove the actual plug part leaving the board assembly.. solder the three wires needed to each side of the board and connect the right plug for the v2 to the end.. this allowing a quick connect plug system... hhhhmmmmm... i like this i do... so no need to cut up the plx box.. etc etc..