COM port settings?

[marc_w]

Does HPT need any specific COM port settings in order to connect to the cable/VCM?

My Dell Latitude D600's primary function (unfortunately) is my work laptop. Today a co-worker and I were trying to connect the thing to another computer at work, through the COM port, without success.

For what it's worth - We were having problems connecting using Hyperterm to a Sun V250. Hyperterm hung my laptop more than once - something I've never had happen before. We used a number of different null-modem cables, to crossovers to straight throughs with 9pin to 10baseT connector. We DID mess around with the "basic" COM port settings, moving the baud rate and flow control, but I set it back the way it was.

So... Low and behold, tonight I can't get the HPT scanner or flash tools to connect to my VCM.

When I bring up the scanner, and click "Start Scanning", the "Command" box in the lower left of the screen says: "Cable Connect: 3" (pause) "Cable Connect: 1" (pause) "Idle."

The "Cable Status" box goes from "No Open Ports" to "Cable Not Found."

I set the COM port defaults, disabled/enabled, reinstalled the driver, and of course rebooted without any success.

I'm set at 9600, 8, no, 1, no, by default. FIFO enabled. I tried 19200, but that didn't do anything.

This doesn't sound like a HPT problem, does it?

Is there any sort of test I can do via command line, or even with a mutimeter to see if the HPT cable/box/OBDII link is okay?

Thanks,
-marc

[marc_w]

Also, I checked fuses, and all looked fine during a quick glance.

I don't see any OBDII port specific fuse. Ciggy lighter works.

[Casey]

We just tell Windows what the port settings should be.
If there is something that hogs the port (Palm Pilot, UPS software, etc) we can never connect.

On the ports settings try:

Bits Per second: 11520
Data: 8
Parity: None
Stop: 1
Flow Control: None


For a quick com port test, Use Hyperterminal and short
pins 2,3 together on the DB9 connector.
This is a cheap loopback test.
As you type on Hyperterminal you should see it on the screen. If not your com port is dead.

Ken

[marc_w]

Great idea on the pin 2 and 3... I tried it, and Hyperterm doesn't work.

Thanks for the help, I appreciate it!

[WS6snake-eater]

I'm having this same problem...my comm port checks out ok...what fuse do I look for to check the OBDII port?

Matt

BTW mine has been working fine for almost 2 months now. Today is the 1st time that it would not connect.

[Casey]

Cigarette lighter fuse.
Also make sure you don't have the scanner running while trying to read/write. The scanner is always connected to the com port to speed up the scan connection process.


The second from the left "lightning bolt" on the scanner tool bar will force the scanner to disconnect from the com port


Ken

[WS6snake-eater]

Ok checked the fuse and all is well...I can not get anything to connect. I'm starting to think that my diag port has gone bad. Which com port to you guys recomend. My serial port is com 1 should I try and force it to a different com.

[WS6snake-eater]

WTF...ok I just took out and checked every fuse in the "in car" fuse box...All checked out OK. So I figured what the hell I'm going to give it another shot. and low and behold it works...I wonder if one of the fuese was just loose. I wouldn't think so though because I checked my cig lighter with my cell phone charger and it worked. Oh well all is better now

[marc_w]

Cool.

I had to get my system board replaced. Apparently we fried something.

[WS6snake-eater]

Ok if I short pins 2 and 3 directly at the port I do get a loopback, however if I plug in the extension cable and short pins 2 and 3 I do not. Does this mean I have a bad db9 extension cable or does the placement of the 2 and 3 pins change, ie. do they crossover, like a peer to peer network cable?

[WS6snake-eater]

I just tried it with 2 different DB9 cables and neither one will pass a loopback test. However if you jump the 2 - 3 pins directly at the port it will loop back just fine. :huh2: