On the theory that a picture is worth a thousand words, here is that
the standard updater looks like;

http://www.butterfly-store.de/en/Upd...isplay,i13.htm

Bob


On Mon, 17 Dec 2012 18:11:31 -0600, Bob Gibbons
wrote:

On Mon, 17 Dec 2012 09:02:00 -0800 (PST), wrote:
.... text deleted

I looked at the update information, and although it specified what connector
pins on the display connector (RJ-12) were to be connected to what pins on a PC
serial connector, it didn't specify the connector itself or address the issue of how
one determines whether or not the PC can supply 3.3vdc on pin 5. I emailed the
Butterfly folks, and I have copied the reply here. You will note that the reply still
doesn't directly address the 3.3vdc issue, but at this point I'm confident enough
that its not going to be a problem that I plan to fabricate a RJ12-DB9 cable and
give it a whirl.

Frank (TA)

I have one of the standard Flarm display updaters. It uses a normal 9v
transister-type battery (e.g., MN1604) that is fed into a voltage
regulator that drops the output to the required 3.3v. Two cables are
involved, a standard DB9 going to the serial port, and a RJ-11 (or
RJ-12) going to the display.

I have used this unit both with older PCs with a serial port, and with
newer PCs using a serial-usb converter.

Another option for those electrically inclined is shown on 3U's
website. This approaches uses the USB port directly, at the expense of
more complicated circuitry.
https://sites.google.com/site/threeu...terfly-display

Bob