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cordes
09-22-2007, 11:41 PM
OK, I picked up this cable from mouser for $20. http://www.mouser.com/search/ProductDetail.aspx?R=TTL-232Rvirtualkey62620000virtualkey626-DLP-TTL232R

One person who I have been talking to seems to think that it will work, so I am going to give it a go. I have decided to pick up the 5c gnd tx and rx from the LM where the connector pins first inter the board.

My question is, when minimopar lists the tx and rx on the red connector on the site, that is the pin that actually does the transmitting and receiving correct? I am going to hook it up that way, so that the tx from the cable will be soldered to where the rx pin first meets the LM. I will post up some pics when I am done so that you guys can see what I am talking about, and also give a description of how I did everything. Let me know if I am way off base here. (I probably am) :amen:

cordes
09-23-2007, 12:25 AM
Here are a couple pics. Tell me what you think, well other than the fact that my soldering stinks.

http://www.turbo-mopar.com/forums/photopost/data/500/lmloggingcable.jpg


This one does not show it very well, but the LM is on the table several feet away. I will be able to plug my laptop in and log from the drivers seat if I wanted to I would guess. The cable is just press fit in the case. It is in there very snug, but I don't think it will harm anything.
http://www.turbo-mopar.com/forums/photopost/data/500/cablelength.jpg

ETA: I will fire it up in the morning, and let you guys know if it works. The cable might be fine of course, but I have a feeling it will take me some time to figure out how to use the program. :p

RoadWarrior222
09-23-2007, 10:16 AM
Serial connections get confusing as to whether you're working on a DTE or DCE scheme (Data Terminal Equipment i.e. terminal or computer) (Data Communication Equipment, i.e. modem etc) since DCE will have the RX and TX pins crossed, and may have them labelled "backwards". So where you'd cross the wiring over for a DTE-DTE connection, you'd go "straight through" for a DTE-DCE connection. So depends what logic the designer was following at the time. If you get issues, then read the number off the chips onboard, try and trace the TX and RX wires to which pins they go to and google the datasheets for the chips.

cordes
09-23-2007, 11:04 AM
Serial connections get confusing as to whether you're working on a DTE or DCE scheme (Data Terminal Equipment i.e. terminal or computer) (Data Communication Equipment, i.e. modem etc) since DCE will have the RX and TX pins crossed, and may have them labelled "backwards". So where you'd cross the wiring over for a DTE-DTE connection, you'd go "straight through" for a DTE-DCE connection. So depends what logic the designer was following at the time. If you get issues, then read the number off the chips onboard, try and trace the TX and RX wires to which pins they go to and google the datasheets for the chips.

Thanks for the reply. I am suree if I googled some of that it would not sounds so much like Charlie Brown's teacher, but I will be able to figure it out. Thanks again. :thumb:

cordes
09-23-2007, 01:18 PM
Should my laptop smoke when the cable is plugged into it? Also, the fuel pump won't prime etc. now. I will be trying to fix the problem and ideas would be great.

RoadWarrior222
09-23-2007, 01:32 PM
ruh roh. You let the magic smoke out, not good, not good.

I can't think why it would do that with TX and RX crossed, with power and ground crossed maybe...

Hmmm thinking maybe you should only have had TX RX and GND wired on the LM side... and sticking the +5V together did something funky. Gotta try the other PC to see the datasheet, won't load on this one.

cordes
09-23-2007, 01:37 PM
Ok, when I unplugged the LM and looked at the rec conector, it hit me that the pins on the LM are mirrored from when you are looking at the pin. So I had the gnd and 5v switched, which I would assume is the cause of the smoking. I then also had to move the yellow wire to the other side of the orange one. I will try this board again and see if it works.

Aries_Turbo
09-30-2007, 09:08 AM
any luck so far? (yes ive been reading on moparchem as well... just felt like asking here)

Brian

mcsvt
09-30-2007, 09:44 AM
Ok, when I unplugged the LM and looked at the rec conector, it hit me that the pins on the LM are mirrored from when you are looking at the pin. So I had the gnd and 5v switched, which I would assume is the cause of the smoking. I then also had to move the yellow wire to the other side of the orange one. I will try this board again and see if it works.

I did the same thing when I was making my serial connector to use with MiniDash, opps....

cordes
09-30-2007, 10:27 AM
any luck so far? (yes ive been reading on moparchem as well... just felt like asking here)

Brian

Not as of yet. I have been harvesting and working a lot at school this week so I have not been able to connect the Rx and Tx wires to see if I can get a terminal emulator program to echo back anything to me. If I can't get that to work I will solder it up the way Geoff has his, and go from there.

cordes
10-03-2007, 07:53 PM
Ok, I have tried just about every way I can think of to hook up this cable to the LM. I have swapped the tx and rx lines when using my soldering locations, I have tied them together, and I have used Geoff's spots per his serial thread.

The only thing I can get going for me is that I can get a terminal emulator that I downloaded to open a connection for com port 3 and com port 5. It won't open the connections unless the cable is plugged in, so I guess I am doing that right. I have been unable to find a simple terminal program that is easy enough for me to intuitively use so that I can get the thing to echo back what I type in. I think I should be selecting com port 5 when I am using a logging program since I see the cable listed under com port 5 in the devise manager. Chem only goes up to 4, and LMLog won't do anything for me.

Any further suggestions would be greatly appreciated, as I am about ready to seriously smash something.

DB-Rocket
10-03-2007, 08:21 PM
Are you trying to hook USB up for fun?

If the serial port method works, why not just use a USB to serial adapter?
They are like $30 at radio shack.

Thats how I program my satellite recievers from my laptop with no serial port.

cordes
10-03-2007, 09:28 PM
Are you trying to hook USB up for fun?

If the serial port method works, why not just use a USB to serial adapter?
They are like $30 at radio shack.

Thats how I program my satellite recievers from my laptop with no serial port.

This cable is only $20. If we can get them to work that is as cheap and easy as it can get for logging.

ShelGame
10-04-2007, 08:04 AM
Are you trying to hook USB up for fun?

If the serial port method works, why not just use a USB to serial adapter?
They are like $30 at radio shack.

Thats how I program my satellite recievers from my laptop with no serial port.

Except that our ECU's don't have RS232. Only TTL. So that type of USB-Serial converter isn't enough. You'll need even more hardware to convert the ECU signals to RS232.

This cable goes straight from USB to TTL and shows up as a COM port in the PC. Simple. If we can get it to work. I haven't even had a chance to open the package on mine yet...