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badmrb

Active Member
Im looking for info on wiring the P-mag to talk with a laptop.

Currently my right ignition is a Jeff Rose Electroair that has always worked fine. Im replacing the left slick mag with a Pmag. My goal is to try and have their timing curves close or at least match at my normal cruise settings.

To that end I am attempting to get the Pmag to talk to my laptop.

Is there anyone who has done this successfully that might have pics/ advice on making it all work.

I wired up a cord to what I thought matched their diagram and used a usb/serial adapter to laptop. After nothing happened and verifying everything I realize their picture of the serial 9 pin has the top row numbers matching both my plugs but the bottom row numbers are reversed. So, now Im worried that the wiring might not be correct.

Also, is there info out there on the settings for the comm port like baud rate etc. . .that might need to be changed. Laptop is windows 7.

Thanks.
 
The TX of the Pmag must go to the RX pin on the serial port and vice versa. If it does not work, just flip em around and try it. Also you must remove the A curve jumper...

The software will set its own baud rate when it takes over the port. It is critical to know what port the USB adapter is using so you can ensure the software is set to use it. Some of those USB to serial adapters don't work very well.
 
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Pin 5 is ground and pin 2 and 3 are trans/ and recieve. I think they are right and switching 3&2 makes no difference.

I think the windows 7 wont talk with the usb/serial adapter. Mine was ordered cheap online. The local radioshack carries one that is almost $40 but most of the reviews says folks cant get windows 7 to install drivers for it.

Next question, anyone know what adapter they are using for the serial to usb that works with windows 7. And where did they get it?
 
find an old computer

If you can find an old computer running xp with a comm port it will work fine. I had trouble with the cheap RS232 serial to usb converters. Some work and some don't. I can't remember the brand I have but the ones that work look exactly like the ones that don't. On my -4 I have an onboard computer running XP, connected to both Pmags through a DPDT switch and it works perfectly. You can even use it inflight to see what the Pmag is doing. Don't give up.
 
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