Mini Dash question. Building DIY rs232 converter.

[Gearjamer]

Hey to those who know. I built my own converter for ttl to RS232. I did this because the local electronic shop had all the parts. The problem is they didn't have a schematic. So I tried to find one on the net. I can't find what signal need to be going between the Palm RS232 and the converter chip. Right now I only have Rx, Tx, and ground. I think I need the sync signal or speed signal and don't know where to get that from. Can anyone help me?

Thanks

[ShelGame]

You shouldn't need either the sync or speed lines for communications with the car. If you're going to use the converter with other devices, you might need other signals.

[Gearjamer]

I've tried it with both and I'm getting no comm. I figured it was an issue with my converter construction. I've triple checked all my connections. Is there a setting I'm missing on my Palm M105. I've got the latest beta so it will run on 3.5.3. The program comes up nice no glitches and I'm running after burner at 30mhz. On the car connection I'm using the 12vdc through a 5vdc solid state regulator, Tx, Rx, and signal ground connections. I thought I needed to enter the memory address as well but can't find where I would do that. Thanks for the help

Bill

[ShelGame]

What ECU do you have in the car? P/N?

Also, have you tried a loopback test with a simple terminal program? Simply connect the Rx and Tx lines together on the ECU side of the converter (obviously, it needs to be powered up). Anything you type in a terminal program should be echoed back to the terminal. If not, then swap the Rx and Tx lines on the Palm end of the interface. If it still doesn't work, then the interface simply isn't working. If the loopback test did work, then you probably need to swap the Rx and Tx lines at the ECU.

[Gearjamer]

I'll give that a try. Thanx! Is hyperterminal on the palm or do I have to down load it?

[ShelGame]

You'll have to download one. There are many out there...

[Gearjamer]

Ok feeling stupid:confused: I can't find hyperterminal for a Palm. They are all for DOS, Windows, or Linux. Can someone give me a name of a good program to use?

[ShelGame]

Look for a program called "Online" or "CSOnline". There's also one called "Portabella" that I've never tried...