Gm 160 and 8192 ALDL

[In-Tech]

Hello Everyone,
I'm having a brain fart since it's been about 25 years since I built my ALDL cables.
My original design used max233 and 7407 inverter chips. Now I want to build a FTDI usb version. I can't remember if the ECM/PCM wants to talk at TTL or Serial and I am hoping some of you can just blurt it out as I don't want to have to read the entire interweb again :laugh: From memory it seems to me the ECM/PCM talks at TTL and I needed my max chip to convert it so the lappy could listen/talk. FACK, it sucks getting old :thumbsup:

My original files are gone 50 laptops ago is why I gotta rethink :mad1:

[kur4o]

160 is 12volts signal. A simple 2 transistor adapter to serial seems to work best. putting some 10k resistor on the aldl connector makes the pcm to dumps continuously data at 160 baud.

8192 is 5volts signal. You can get a cheap chinese usb ftdi ttl to serial converter for around $2. get the red ones with type b connector.

[In-Tech]

Hiya kur4o,
Thanks for the reply, yes, I built the transistor based 160 baud before too :)
I thought I read somewhere that the ftdi ttl cable doesn't work with 160 baud. I never paid much attention to the posts because my existing serial stuff is flawless on both bauds as well as many other things. My original crapola had the chips powered via a ps2 port and is the biggest reason I am looking to make my new one USB. When I build stuff I try to make it as universal as possible. My original worked on EVERYFOCKINGTHING including clock jitter iso7816 sniffing :rockon:
Thanks again.

[In-Tech]

BTW, if the ftdi to ttl works with 160 baud please chime in, then I don't have to build anything :)

[kur4o]

The only one I made to work with 160 baud was the 2 transistor ones, the current 232 chips also don`t work good enough.

I also never managed to make the 2 transistor to work with 8192.
You will need at least one 8192 and one 160 baud cables.

[In-Tech]

Hiya kur4o,
The max 233 is basically a 232 but has internal caps. To me the key is the 7407 and although it is called an inverter, it basically "cleans" the signal. As mentioned, the design I did back in the 90's works flawlessly on 160 to 255k, even with clock jitter. I just want to make something more current using USB. I'm not quite sure what it will take and based on what you said, my memory is coming back to my thoughts back then. Wish me luck :jfj:

[kur4o]

I `ve had best luck with these ones. Cheap and easy to put anywhere in the car.

https://www.ebay.com/itm/224246089175?hash=item34361bc5d7:g:ZNEAAOSwJhhfUPC Q