serial port docking sled gpsapp problem

Ok,

Here's the deal. I just went out and bought a nifty new GPS receiver for my car. I wired it up to power and serial and everything seems to check out OK, except when the antenna is plugged into the serial port coming out of the docking sled. GPSapp just sits in the "Waiting ..." mode.

When I connect the antenna's serial cable directly to the back of the RIO's serial port and use external power and force DC mode, GPSapp detects serial output from the antenna instantly, and there is much rejoicing.

I installed a straight through gender bender between the female end of the antenna serial cable and the female end of the serial cable coming from the sled.

I read something in the FAQ about the sled having a crossed cable vs. a null modem and something about the ground missing on some sleds...

http://www.riocar.org/modules.php?op=modload&name=FAQ&file=index&myfaq=yes&id_cat=8&categories=Known+problems+and+troubleshooting+questions&faqent=74#74

What angle should I start troubleshooting from?

TIA,

lothar

Why not try a crossover instead of a straight through, it should be cheap enough...

My responses to this are:

Here
Here
and
Here

Yeah you'll need to cross over TxD and Rxd to use the sled, and also remember that the sled's serial provides 12V on pin 4, and also telephone mute and dimmer lines - none of which are present in the on-empeg serial port. You will need to lose these lines.

Since you (from your description anyway) appear to have a new reciever with a predefined serial connection, it sounds like your best option is to build a short cable to do this, using male connectors at both ends. (If you use a commercial available NULL modem adaptor then the 12V will still be crossed (to which pine

Cross pins 2 and 3
Wire pin 5 straight through. (Gnd)
Don't connect anything else.

The docking sled serial port is really screwy. You will need to wire a custom cable that only uses pins 2, 3, and 5, and 2/3 will need to be swapped compared to the player's serial port. FAQ entry is here.

Is there an echo here?

I don't think Tony reads responses very thoroughly. That seems to happen all the time. Plus, it increases his post count, which obviously needs doing, since he's only got about four times as many posts as his closest competitor.

Thanks everyone for the flood of suggestions...

<building custom cable as I am writing this (talented aren't I?)>

let everyone know how it goes...

It works!!! I made a custom connector per Tony's specs and GPSapp is working perfectly.

Now if only I could get empgps to work as well...

-lothar

what does empgps do that you want?

I made a custom connector per Tony's specs and GPSapp is working perfectly.

To be fair, Genixia beat me to the spec posting. I just wanted to plug the FAQ when I replied.

I guess the right question is "what does empgps do that gpsapp doesn't"