Just a quick update. I have not yet resolved the problems with the Sparkfun FT232RL but I'm still working on it. I'll let you know what I come up with.

What happens is that the USB adapter appears...

Remember me from 2 years ago? :D I'm back to messing with DIY ALDL setup on my 7747, wanted to share updates. Hope it's not old news. Using Sparkfun FTDI Basic Breakout 5V with an emitter-follower...

Yes, I know. :) Hence a "start" of a DIY cable. :) Sorry for the confusion. What I meant was, you start with that handy cable, then add the FTDI stuff. I'm still working on what that stuff would be....

Okey doke... I broke out my o-scope to look at waveforms, looked fine whether vehicle running or not so that wasn't the problem. I thought it'd be interesting to try and buffer the signal with a PNP...

Thanks. Not sure what happened.

So with ftdi connected the ses light flickers really fast and sort of randomly. And data stream stops. Not sure what's up. Going to dig into that next. Hard to know...

Mine had 2400 baud (I think) and RS-232 echo checked. I forget where I downloaded it, possibly here. $42-1227747-V4.2.adx *shrug*

In TunerPro RT, I had to set 4800 baud and uncheck RS232 echo and it started acquiring data, and revealed an issue to chase down.

Ok, I found the 5V FTDI breakout board and it worked, sort of.

I can see data coming in over one of the serial ports. I tied tx/rx together and TunerPro RT sees it when the ECM is off or...

Glad I found this thread. I'm trying to build an ALDL USB cable using a different TTL serial to USB converter.

WinALDL can't connect to it and neither can TunerPro RT. Only one of my terminal...